1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 -- 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 Contracts; use Contracts;
34 with Debug; use Debug;
35 with Einfo; use Einfo;
36 with Elists; use Elists;
37 with Errout; use Errout;
38 with Exp_Disp; use Exp_Disp;
39 with Exp_Dist; use Exp_Dist;
40 with Exp_Dbug; use Exp_Dbug;
41 with Ghost; use Ghost;
43 with Lib.Xref; use Lib.Xref;
44 with Namet; use Namet;
45 with Nmake; use Nmake;
46 with Nlists; use Nlists;
48 with Output; use Output;
49 with Restrict; use Restrict;
50 with Rtsfind; use Rtsfind;
52 with Sem_Aux; use Sem_Aux;
53 with Sem_Cat; use Sem_Cat;
54 with Sem_Ch3; use Sem_Ch3;
55 with Sem_Ch6; use Sem_Ch6;
56 with Sem_Ch8; use Sem_Ch8;
57 with Sem_Ch10; use Sem_Ch10;
58 with Sem_Ch12; use Sem_Ch12;
59 with Sem_Ch13; use Sem_Ch13;
60 with Sem_Disp; use Sem_Disp;
61 with Sem_Eval; use Sem_Eval;
62 with Sem_Prag; use Sem_Prag;
63 with Sem_Util; use Sem_Util;
64 with Sem_Warn; use Sem_Warn;
65 with Snames; use Snames;
66 with Stand; use Stand;
67 with Sinfo; use Sinfo;
68 with Sinput; use Sinput;
70 with Uintp; use Uintp;
72 package body Sem_Ch7 is
74 -----------------------------------
75 -- Handling private declarations --
76 -----------------------------------
78 -- The principle that each entity has a single defining occurrence clashes
79 -- with the presence of two separate definitions for private types: the
80 -- first is the private type declaration, and the second is the full type
81 -- declaration. It is important that all references to the type point to
82 -- the same defining occurrence, namely the first one. To enforce the two
83 -- separate views of the entity, the corresponding information is swapped
84 -- between the two declarations. Outside of the package, the defining
85 -- occurrence only contains the private declaration information, while in
86 -- the private part and the body of the package the defining occurrence
87 -- contains the full declaration. To simplify the swap, the defining
88 -- occurrence that currently holds the private declaration points to the
89 -- full declaration. During semantic processing the defining occurrence
90 -- also points to a list of private dependents, that is to say access types
91 -- or composite types whose designated types or component types are
92 -- subtypes or derived types of the private type in question. After the
93 -- full declaration has been seen, the private dependents are updated to
94 -- indicate that they have full definitions.
96 -----------------------
97 -- Local Subprograms --
98 -----------------------
100 procedure Analyze_Package_Body_Helper (N : Node_Id);
101 -- Does all the real work of Analyze_Package_Body
103 procedure Check_Anonymous_Access_Types
104 (Spec_Id : Entity_Id;
106 -- If the spec of a package has a limited_with_clause, it may declare
107 -- anonymous access types whose designated type is a limited view, such an
108 -- anonymous access return type for a function. This access type cannot be
109 -- elaborated in the spec itself, but it may need an itype reference if it
110 -- is used within a nested scope. In that case the itype reference is
111 -- created at the beginning of the corresponding package body and inserted
112 -- before other body declarations.
114 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id);
115 -- Called upon entering the private part of a public child package and the
116 -- body of a nested package, to potentially declare certain inherited
117 -- subprograms that were inherited by types in the visible part, but whose
118 -- declaration was deferred because the parent operation was private and
119 -- not visible at that point. These subprograms are located by traversing
120 -- the visible part declarations looking for non-private type extensions
121 -- and then examining each of the primitive operations of such types to
122 -- find those that were inherited but declared with a special internal
123 -- name. Each such operation is now declared as an operation with a normal
124 -- name (using the name of the parent operation) and replaces the previous
125 -- implicit operation in the primitive operations list of the type. If the
126 -- inherited private operation has been overridden, then it's replaced by
127 -- the overriding operation.
129 procedure Install_Package_Entity (Id : Entity_Id);
130 -- Supporting procedure for Install_{Visible,Private}_Declarations. Places
131 -- one entity on its visibility chain, and recurses on the visible part if
132 -- the entity is an inner package.
134 function Is_Private_Base_Type (E : Entity_Id) return Boolean;
135 -- True for a private type that is not a subtype
137 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean;
138 -- If the private dependent is a private type whose full view is derived
139 -- from the parent type, its full properties are revealed only if we are in
140 -- the immediate scope of the private dependent. Should this predicate be
141 -- tightened further???
143 function Requires_Completion_In_Body
146 Do_Abstract_States : Boolean := False) return Boolean;
147 -- Subsidiary to routines Unit_Requires_Body and Unit_Requires_Body_Info.
148 -- Determine whether entity Id declared in package spec Pack_Id requires
149 -- completion in a package body. Flag Do_Abstract_Stats should be set when
150 -- abstract states are to be considered in the completion test.
152 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id);
153 -- Outputs info messages showing why package Pack_Id requires a body. The
154 -- caller has checked that the switch requesting this information is set,
155 -- and that the package does indeed require a body.
157 --------------------------
158 -- Analyze_Package_Body --
159 --------------------------
161 procedure Analyze_Package_Body (N : Node_Id) is
162 Loc : constant Source_Ptr := Sloc (N);
166 Write_Str ("==> package body ");
167 Write_Name (Chars (Defining_Entity (N)));
168 Write_Str (" from ");
169 Write_Location (Loc);
174 -- The real work is split out into the helper, so it can do "return;"
175 -- without skipping the debug output.
177 Analyze_Package_Body_Helper (N);
181 Write_Str ("<== package body ");
182 Write_Name (Chars (Defining_Entity (N)));
183 Write_Str (" from ");
184 Write_Location (Loc);
187 end Analyze_Package_Body;
189 ---------------------------------
190 -- Analyze_Package_Body_Helper --
191 ---------------------------------
193 procedure Analyze_Package_Body_Helper (N : Node_Id) is
194 procedure Hide_Public_Entities (Decls : List_Id);
195 -- Attempt to hide all public entities found in declarative list Decls
196 -- by resetting their Is_Public flag to False depending on whether the
197 -- entities are not referenced by inlined or generic bodies. This kind
198 -- of processing is a conservative approximation and may still leave
199 -- certain entities externally visible.
201 procedure Install_Composite_Operations (P : Entity_Id);
202 -- Composite types declared in the current scope may depend on types
203 -- that were private at the point of declaration, and whose full view
204 -- is now in scope. Indicate that the corresponding operations on the
205 -- composite type are available.
207 --------------------------
208 -- Hide_Public_Entities --
209 --------------------------
211 procedure Hide_Public_Entities (Decls : List_Id) is
212 function Contains_Subp_Or_Const_Refs (N : Node_Id) return Boolean;
213 -- Subsidiary to routine Has_Referencer. Determine whether a node
214 -- contains a reference to a subprogram or a non-static constant.
215 -- WARNING: this is a very expensive routine as it performs a full
218 function Has_Referencer
220 Top_Level : Boolean := False) return Boolean;
221 -- A "referencer" is a construct which may reference a previous
222 -- declaration. Examine all declarations in list Decls in reverse
223 -- and determine whether once such referencer exists. All entities
224 -- in the range Last (Decls) .. Referencer are hidden from external
227 ---------------------------------
228 -- Contains_Subp_Or_Const_Refs --
229 ---------------------------------
231 function Contains_Subp_Or_Const_Refs (N : Node_Id) return Boolean is
232 Reference_Seen : Boolean := False;
234 function Is_Subp_Or_Const_Ref
235 (N : Node_Id) return Traverse_Result;
236 -- Determine whether a node denotes a reference to a subprogram or
237 -- a non-static constant.
239 --------------------------
240 -- Is_Subp_Or_Const_Ref --
241 --------------------------
243 function Is_Subp_Or_Const_Ref
244 (N : Node_Id) return Traverse_Result
249 -- Detect a reference of the form
252 if Nkind (N) in N_Subprogram_Call
253 and then Is_Entity_Name (Name (N))
255 Reference_Seen := True;
258 -- Detect a reference of the form
259 -- Subp'Some_Attribute
261 elsif Nkind (N) = N_Attribute_Reference
262 and then Is_Entity_Name (Prefix (N))
263 and then Present (Entity (Prefix (N)))
264 and then Is_Subprogram (Entity (Prefix (N)))
266 Reference_Seen := True;
269 -- Detect the use of a non-static constant
271 elsif Is_Entity_Name (N)
272 and then Present (Entity (N))
273 and then Ekind (Entity (N)) = E_Constant
275 Val := Constant_Value (Entity (N));
278 and then not Compile_Time_Known_Value (Val)
280 Reference_Seen := True;
286 end Is_Subp_Or_Const_Ref;
288 procedure Find_Subp_Or_Const_Ref is
289 new Traverse_Proc (Is_Subp_Or_Const_Ref);
291 -- Start of processing for Contains_Subp_Or_Const_Refs
294 Find_Subp_Or_Const_Ref (N);
296 return Reference_Seen;
297 end Contains_Subp_Or_Const_Refs;
303 function Has_Referencer
305 Top_Level : Boolean := False) return Boolean
311 Has_Non_Subp_Const_Referencer : Boolean := False;
312 -- Flag set for inlined subprogram bodies that do not contain
313 -- references to other subprograms or non-static constants.
320 -- Examine all declarations in reverse order, hiding all entities
321 -- from external visibility until a referencer has been found. The
322 -- algorithm recurses into nested packages.
324 Decl := Last (Decls);
325 while Present (Decl) loop
327 -- A stub is always considered a referencer
329 if Nkind (Decl) in N_Body_Stub then
332 -- Package declaration
334 elsif Nkind (Decl) = N_Package_Declaration
335 and then not Has_Non_Subp_Const_Referencer
337 Spec := Specification (Decl);
339 -- Inspect the declarations of a non-generic package to try
340 -- and hide more entities from external visibility.
342 if not Is_Generic_Unit (Defining_Entity (Spec)) then
343 if Has_Referencer (Private_Declarations (Spec))
344 or else Has_Referencer (Visible_Declarations (Spec))
352 elsif Nkind (Decl) = N_Package_Body
353 and then Present (Corresponding_Spec (Decl))
355 Decl_Id := Corresponding_Spec (Decl);
357 -- A generic package body is a referencer. It would seem
358 -- that we only have to consider generics that can be
359 -- exported, i.e. where the corresponding spec is the
360 -- spec of the current package, but because of nested
361 -- instantiations, a fully private generic body may export
362 -- other private body entities. Furthermore, regardless of
363 -- whether there was a previous inlined subprogram, (an
364 -- instantiation of) the generic package may reference any
365 -- entity declared before it.
367 if Is_Generic_Unit (Decl_Id) then
370 -- Inspect the declarations of a non-generic package body to
371 -- try and hide more entities from external visibility.
373 elsif not Has_Non_Subp_Const_Referencer
374 and then Has_Referencer (Declarations (Decl))
381 elsif Nkind (Decl) = N_Subprogram_Body then
382 if Present (Corresponding_Spec (Decl)) then
383 Decl_Id := Corresponding_Spec (Decl);
385 -- A generic subprogram body acts as a referencer
387 if Is_Generic_Unit (Decl_Id) then
391 -- An inlined subprogram body acts as a referencer
393 if Is_Inlined (Decl_Id)
394 or else Has_Pragma_Inline (Decl_Id)
396 -- Inspect the statements of the subprogram body
397 -- to determine whether the body references other
398 -- subprograms and/or non-static constants.
401 and then not Contains_Subp_Or_Const_Refs (Decl)
403 Has_Non_Subp_Const_Referencer := True;
409 -- Otherwise this is a stand alone subprogram body
412 Decl_Id := Defining_Entity (Decl);
414 -- An inlined body acts as a referencer. Note that an
415 -- inlined subprogram remains Is_Public as gigi requires
416 -- the flag to be set.
418 -- Note that we test Has_Pragma_Inline here rather than
419 -- Is_Inlined. We are compiling this for a client, and
420 -- it is the client who will decide if actual inlining
421 -- should occur, so we need to assume that the procedure
422 -- could be inlined for the purpose of accessing global
425 if Has_Pragma_Inline (Decl_Id) then
427 and then not Contains_Subp_Or_Const_Refs (Decl)
429 Has_Non_Subp_Const_Referencer := True;
434 Set_Is_Public (Decl_Id, False);
438 -- Exceptions, objects and renamings do not need to be public
439 -- if they are not followed by a construct which can reference
440 -- and export them. The Is_Public flag is reset on top level
441 -- entities only as anything nested is local to its context.
443 elsif Nkind_In (Decl, N_Exception_Declaration,
444 N_Object_Declaration,
445 N_Object_Renaming_Declaration,
446 N_Subprogram_Declaration,
447 N_Subprogram_Renaming_Declaration)
449 Decl_Id := Defining_Entity (Decl);
452 and then not Is_Imported (Decl_Id)
453 and then not Is_Exported (Decl_Id)
454 and then No (Interface_Name (Decl_Id))
456 (not Has_Non_Subp_Const_Referencer
457 or else Nkind (Decl) = N_Subprogram_Declaration)
459 Set_Is_Public (Decl_Id, False);
466 return Has_Non_Subp_Const_Referencer;
471 Discard : Boolean := True;
472 pragma Unreferenced (Discard);
474 -- Start of processing for Hide_Public_Entities
477 -- The algorithm examines the top level declarations of a package
478 -- body in reverse looking for a construct that may export entities
479 -- declared prior to it. If such a scenario is encountered, then all
480 -- entities in the range Last (Decls) .. construct are hidden from
481 -- external visibility. Consider:
489 -- package body Pack is
490 -- External_Obj : ...; -- (1)
492 -- package body Gen is -- (2)
493 -- ... External_Obj ... -- (3)
496 -- Local_Obj : ...; -- (4)
499 -- In this example Local_Obj (4) must not be externally visible as
500 -- it cannot be exported by anything in Pack. The body of generic
501 -- package Gen (2) on the other hand acts as a "referencer" and may
502 -- export anything declared before it. Since the compiler does not
503 -- perform flow analysis, it is not possible to determine precisely
504 -- which entities will be exported when Gen is instantiated. In the
505 -- example above External_Obj (1) is exported at (3), but this may
506 -- not always be the case. The algorithm takes a conservative stance
507 -- and leaves entity External_Obj public.
509 Discard := Has_Referencer (Decls, Top_Level => True);
510 end Hide_Public_Entities;
512 ----------------------------------
513 -- Install_Composite_Operations --
514 ----------------------------------
516 procedure Install_Composite_Operations (P : Entity_Id) is
520 Id := First_Entity (P);
521 while Present (Id) loop
523 and then (Is_Limited_Composite (Id)
524 or else Is_Private_Composite (Id))
525 and then No (Private_Component (Id))
527 Set_Is_Limited_Composite (Id, False);
528 Set_Is_Private_Composite (Id, False);
533 end Install_Composite_Operations;
537 Save_Ghost_Mode : constant Ghost_Mode_Type := Ghost_Mode;
540 Last_Spec_Entity : Entity_Id;
545 -- Start of processing for Analyze_Package_Body_Helper
548 -- Find corresponding package specification, and establish the current
549 -- scope. The visible defining entity for the package is the defining
550 -- occurrence in the spec. On exit from the package body, all body
551 -- declarations are attached to the defining entity for the body, but
552 -- the later is never used for name resolution. In this fashion there
553 -- is only one visible entity that denotes the package.
555 -- Set Body_Id. Note that this will be reset to point to the generic
556 -- copy later on in the generic case.
558 Body_Id := Defining_Entity (N);
560 -- Body is body of package instantiation. Corresponding spec has already
563 if Present (Corresponding_Spec (N)) then
564 Spec_Id := Corresponding_Spec (N);
565 Pack_Decl := Unit_Declaration_Node (Spec_Id);
568 Spec_Id := Current_Entity_In_Scope (Defining_Entity (N));
571 and then Is_Package_Or_Generic_Package (Spec_Id)
573 Pack_Decl := Unit_Declaration_Node (Spec_Id);
575 if Nkind (Pack_Decl) = N_Package_Renaming_Declaration then
576 Error_Msg_N ("cannot supply body for package renaming", N);
579 elsif Present (Corresponding_Body (Pack_Decl)) then
580 Error_Msg_N ("redefinition of package body", N);
585 Error_Msg_N ("missing specification for package body", N);
589 if Is_Package_Or_Generic_Package (Spec_Id)
590 and then (Scope (Spec_Id) = Standard_Standard
591 or else Is_Child_Unit (Spec_Id))
592 and then not Unit_Requires_Body (Spec_Id)
594 if Ada_Version = Ada_83 then
596 ("optional package body (not allowed in Ada 95)??", N);
598 Error_Msg_N ("spec of this package does not allow a body", N);
603 -- A [generic] package body "freezes" the contract of the nearest
604 -- enclosing package body and all other contracts encountered in the
605 -- same declarative part up to and excluding the package body:
607 -- package body Nearest_Enclosing_Package
608 -- with Refined_State => (State => Constit)
612 -- package body Freezes_Enclosing_Package_Body
613 -- with Refined_State => (State_2 => Constit_2)
618 -- with Refined_Depends => (Input => (Constit, Constit_2)) ...
620 -- This ensures that any annotations referenced by the contract of a
621 -- [generic] subprogram body declared within the current package body
622 -- are available. This form of "freezing" is decoupled from the usual
623 -- Freeze_xxx mechanism because it must also work in the context of
624 -- generics where normal freezing is disabled.
626 -- Only bodies coming from source should cause this type of "freezing".
627 -- Instantiated generic bodies are excluded because their processing is
628 -- performed in a separate compilation pass which lacks enough semantic
629 -- information with respect to contract analysis. It is safe to suppress
630 -- the "freezing" of contracts in this case because this action already
631 -- took place at the end of the enclosing declarative part.
633 if Comes_From_Source (N)
634 and then not Is_Generic_Instance (Spec_Id)
636 Analyze_Previous_Contracts (N);
639 -- A package body is Ghost when the corresponding spec is Ghost. Set
640 -- the mode now to ensure that any nodes generated during analysis and
641 -- expansion are properly flagged as ignored Ghost.
643 Set_Ghost_Mode (N, Spec_Id);
645 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
646 Style.Check_Identifier (Body_Id, Spec_Id);
648 if Is_Child_Unit (Spec_Id) then
649 if Nkind (Parent (N)) /= N_Compilation_Unit then
651 ("body of child unit& cannot be an inner package", N, Spec_Id);
654 Set_Is_Child_Unit (Body_Id);
657 -- Generic package case
659 if Ekind (Spec_Id) = E_Generic_Package then
661 -- Disable expansion and perform semantic analysis on copy. The
662 -- unannotated body will be used in all instantiations.
664 Body_Id := Defining_Entity (N);
665 Set_Ekind (Body_Id, E_Package_Body);
666 Set_Scope (Body_Id, Scope (Spec_Id));
667 Set_Is_Obsolescent (Body_Id, Is_Obsolescent (Spec_Id));
668 Set_Body_Entity (Spec_Id, Body_Id);
669 Set_Spec_Entity (Body_Id, Spec_Id);
671 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
674 -- Once the contents of the generic copy and the template are
675 -- swapped, do the same for their respective aspect specifications.
677 Exchange_Aspects (N, New_N);
679 -- Collect all contract-related source pragmas found within the
680 -- template and attach them to the contract of the package body.
681 -- This contract is used in the capture of global references within
684 Create_Generic_Contract (N);
686 -- Update Body_Id to point to the copied node for the remainder of
689 Body_Id := Defining_Entity (N);
693 -- The Body_Id is that of the copied node in the generic case, the
694 -- current node otherwise. Note that N was rewritten above, so we must
695 -- be sure to get the latest Body_Id value.
697 Set_Ekind (Body_Id, E_Package_Body);
698 Set_Body_Entity (Spec_Id, Body_Id);
699 Set_Spec_Entity (Body_Id, Spec_Id);
701 -- Defining name for the package body is not a visible entity: Only the
702 -- defining name for the declaration is visible.
704 Set_Etype (Body_Id, Standard_Void_Type);
705 Set_Scope (Body_Id, Scope (Spec_Id));
706 Set_Corresponding_Spec (N, Spec_Id);
707 Set_Corresponding_Body (Pack_Decl, Body_Id);
709 -- The body entity is not used for semantics or code generation, but
710 -- it is attached to the entity list of the enclosing scope to simplify
711 -- the listing of back-annotations for the types it main contain.
713 if Scope (Spec_Id) /= Standard_Standard then
714 Append_Entity (Body_Id, Scope (Spec_Id));
717 -- Indicate that we are currently compiling the body of the package
719 Set_In_Package_Body (Spec_Id);
720 Set_Has_Completion (Spec_Id);
721 Last_Spec_Entity := Last_Entity (Spec_Id);
723 if Has_Aspects (N) then
724 Analyze_Aspect_Specifications (N, Body_Id);
727 Push_Scope (Spec_Id);
729 -- Set SPARK_Mode only for non-generic package
731 if Ekind (Spec_Id) = E_Package then
732 Set_SPARK_Pragma (Body_Id, SPARK_Mode_Pragma);
733 Set_SPARK_Aux_Pragma (Body_Id, SPARK_Mode_Pragma);
734 Set_SPARK_Pragma_Inherited (Body_Id);
735 Set_SPARK_Aux_Pragma_Inherited (Body_Id);
738 -- Inherit the "ghostness" of the package spec. Note that this property
739 -- is not directly inherited as the body may be subject to a different
740 -- Ghost assertion policy.
742 if Ghost_Mode > None or else Is_Ghost_Entity (Spec_Id) 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(14)).
748 Check_Ghost_Completion (Spec_Id, Body_Id);
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));
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
774 Declare_Inherited_Private_Subprograms (Spec_Id);
777 -- A package body "freezes" the contract of its initial declaration.
778 -- This analysis depends on attribute Corresponding_Spec being set. Only
779 -- bodies coming from source shuld cause this type of "freezing".
781 if Present (Declarations (N)) then
782 Analyze_Declarations (Declarations (N));
783 Inspect_Deferred_Constant_Completion (Declarations (N));
786 -- Verify that the SPARK_Mode of the body agrees with that of its spec
788 if Present (SPARK_Pragma (Body_Id)) then
789 if Present (SPARK_Aux_Pragma (Spec_Id)) then
790 if Get_SPARK_Mode_From_Annotation (SPARK_Aux_Pragma (Spec_Id)) =
793 Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Body_Id)) = On
795 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
796 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
797 Error_Msg_Sloc := Sloc (SPARK_Aux_Pragma (Spec_Id));
799 ("\value Off was set for SPARK_Mode on & #", N, Spec_Id);
803 Error_Msg_Sloc := Sloc (SPARK_Pragma (Body_Id));
804 Error_Msg_N ("incorrect application of SPARK_Mode#", N);
805 Error_Msg_Sloc := Sloc (Spec_Id);
807 ("\no value was set for SPARK_Mode on & #", N, Spec_Id);
811 -- Analyze_Declarations has caused freezing of all types. Now generate
812 -- bodies for RACW primitives and stream attributes, if any.
814 if Ekind (Spec_Id) = E_Package and then Has_RACW (Spec_Id) then
816 -- Attach subprogram bodies to support RACWs declared in spec
818 Append_RACW_Bodies (Declarations (N), Spec_Id);
819 Analyze_List (Declarations (N));
822 HSS := Handled_Statement_Sequence (N);
824 if Present (HSS) then
825 Process_End_Label (HSS, 't', Spec_Id);
828 -- Check that elaboration code in a preelaborable package body is
829 -- empty other than null statements and labels (RM 10.2.1(6)).
831 Validate_Null_Statement_Sequence (N);
834 Validate_Categorization_Dependency (N, Spec_Id);
835 Check_Completion (Body_Id);
837 -- Generate start of body reference. Note that we do this fairly late,
838 -- because the call will use In_Extended_Main_Source_Unit as a check,
839 -- and we want to make sure that Corresponding_Stub links are set
841 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
843 -- For a generic package, collect global references and mark them on
844 -- the original body so that they are not resolved again at the point
847 if Ekind (Spec_Id) /= E_Package then
848 Save_Global_References (Original_Node (N));
852 -- The entities of the package body have so far been chained onto the
853 -- declaration chain for the spec. That's been fine while we were in the
854 -- body, since we wanted them to be visible, but now that we are leaving
855 -- the package body, they are no longer visible, so we remove them from
856 -- the entity chain of the package spec entity, and copy them to the
857 -- entity chain of the package body entity, where they will never again
860 if Present (Last_Spec_Entity) then
861 Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity));
862 Set_Next_Entity (Last_Spec_Entity, Empty);
863 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
864 Set_Last_Entity (Spec_Id, Last_Spec_Entity);
867 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
868 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
869 Set_First_Entity (Spec_Id, Empty);
870 Set_Last_Entity (Spec_Id, Empty);
873 End_Package_Scope (Spec_Id);
875 -- All entities declared in body are not visible
881 E := First_Entity (Body_Id);
882 while Present (E) loop
883 Set_Is_Immediately_Visible (E, False);
884 Set_Is_Potentially_Use_Visible (E, False);
887 -- Child units may appear on the entity list (e.g. if they appear
888 -- in the context of a subunit) but they are not body entities.
890 if not Is_Child_Unit (E) then
891 Set_Is_Package_Body_Entity (E);
898 Check_References (Body_Id);
900 -- For a generic unit, check that the formal parameters are referenced,
901 -- and that local variables are used, as for regular packages.
903 if Ekind (Spec_Id) = E_Generic_Package then
904 Check_References (Spec_Id);
907 -- At this point all entities of the package body are externally visible
908 -- to the linker as their Is_Public flag is set to True. This proactive
909 -- approach is necessary because an inlined or a generic body for which
910 -- code is generated in other units may need to see these entities. Cut
911 -- down the number of global symbols that do not neet public visibility
912 -- as this has two beneficial effects:
913 -- (1) It makes the compilation process more efficient.
914 -- (2) It gives the code generatormore freedom to optimize within each
915 -- unit, especially subprograms.
917 -- This is done only for top level library packages or child units as
918 -- the algorithm does a top down traversal of the package body.
920 if (Scope (Spec_Id) = Standard_Standard or else Is_Child_Unit (Spec_Id))
921 and then not Is_Generic_Unit (Spec_Id)
923 Hide_Public_Entities (Declarations (N));
926 -- If expander is not active, then here is where we turn off the
927 -- In_Package_Body flag, otherwise it is turned off at the end of the
928 -- corresponding expansion routine. If this is an instance body, we need
929 -- to qualify names of local entities, because the body may have been
930 -- compiled as a preliminary to another instantiation.
932 if not Expander_Active then
933 Set_In_Package_Body (Spec_Id, False);
935 if Is_Generic_Instance (Spec_Id)
936 and then Operating_Mode = Generate_Code
938 Qualify_Entity_Names (N);
942 Ghost_Mode := Save_Ghost_Mode;
943 end Analyze_Package_Body_Helper;
945 ---------------------------------
946 -- Analyze_Package_Declaration --
947 ---------------------------------
949 procedure Analyze_Package_Declaration (N : Node_Id) is
950 Id : constant Node_Id := Defining_Entity (N);
951 Par : constant Node_Id := Parent_Spec (N);
953 Is_Comp_Unit : constant Boolean :=
954 Nkind (Parent (N)) = N_Compilation_Unit;
956 Body_Required : Boolean;
957 -- True when this package declaration requires a corresponding body
961 Write_Str ("==> package spec ");
962 Write_Name (Chars (Id));
963 Write_Str (" from ");
964 Write_Location (Sloc (N));
969 Generate_Definition (Id);
971 Set_Ekind (Id, E_Package);
972 Set_Etype (Id, Standard_Void_Type);
974 -- Set SPARK_Mode from context only for non-generic package
976 if Ekind (Id) = E_Package then
977 Set_SPARK_Pragma (Id, SPARK_Mode_Pragma);
978 Set_SPARK_Aux_Pragma (Id, SPARK_Mode_Pragma);
979 Set_SPARK_Pragma_Inherited (Id);
980 Set_SPARK_Aux_Pragma_Inherited (Id);
983 -- A package declared within a Ghost refion is automatically Ghost. A
984 -- child package is Ghost when its parent is Ghost (SPARK RM 6.9(2)).
987 or else (Present (Par)
988 and then Is_Ghost_Entity (Defining_Entity (Unit (Par))))
990 Set_Is_Ghost_Entity (Id);
993 -- Analyze aspect specifications immediately, since we need to recognize
994 -- things like Pure early enough to diagnose violations during analysis.
996 if Has_Aspects (N) then
997 Analyze_Aspect_Specifications (N, Id);
1000 -- Ada 2005 (AI-217): Check if the package has been illegally named in
1001 -- a limited-with clause of its own context. In this case the error has
1002 -- been previously notified by Analyze_Context.
1004 -- limited with Pkg; -- ERROR
1005 -- package Pkg is ...
1007 if From_Limited_With (Id) then
1013 Set_Is_Pure (Id, Is_Pure (Enclosing_Lib_Unit_Entity));
1014 Set_Categorization_From_Pragmas (N);
1016 Analyze (Specification (N));
1017 Validate_Categorization_Dependency (N, Id);
1019 -- Determine whether the package requires a body. Abstract states are
1020 -- intentionally ignored because they do require refinement which can
1021 -- only come in a body, but at the same time they do not force the need
1022 -- for a body on their own (SPARK RM 7.1.4(4) and 7.2.2(3)).
1024 Body_Required := Unit_Requires_Body (Id);
1026 if not Body_Required then
1028 -- If the package spec does not require an explicit body, then there
1029 -- are not entities requiring completion in the language sense. Call
1030 -- Check_Completion now to ensure that nested package declarations
1031 -- that require an implicit body get one. (In the case where a body
1032 -- is required, Check_Completion is called at the end of the body's
1033 -- declarative part.)
1037 -- If the package spec does not require an explicit body, then all
1038 -- abstract states declared in nested packages cannot possibly get
1039 -- a proper refinement (SPARK RM 7.2.2(3)). This check is performed
1040 -- only when the compilation unit is the main unit to allow for
1041 -- modular SPARK analysis where packages do not necessarily have
1044 if Is_Comp_Unit then
1045 Check_State_Refinements
1047 Is_Main_Unit => Parent (N) = Cunit (Main_Unit));
1051 if Is_Comp_Unit then
1053 -- Set Body_Required indication on the compilation unit node, and
1054 -- determine whether elaboration warnings may be meaningful on it.
1056 Set_Body_Required (Parent (N), Body_Required);
1058 if not Body_Required then
1059 Set_Suppress_Elaboration_Warnings (Id);
1063 End_Package_Scope (Id);
1065 -- For the declaration of a library unit that is a remote types package,
1066 -- check legality rules regarding availability of stream attributes for
1067 -- types that contain non-remote access values. This subprogram performs
1068 -- visibility tests that rely on the fact that we have exited the scope
1071 if Is_Comp_Unit then
1072 Validate_RT_RAT_Component (N);
1075 if Debug_Flag_C then
1077 Write_Str ("<== package spec ");
1078 Write_Name (Chars (Id));
1079 Write_Str (" from ");
1080 Write_Location (Sloc (N));
1083 end Analyze_Package_Declaration;
1085 -----------------------------------
1086 -- Analyze_Package_Specification --
1087 -----------------------------------
1089 -- Note that this code is shared for the analysis of generic package specs
1090 -- (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).
1092 procedure Analyze_Package_Specification (N : Node_Id) is
1093 Id : constant Entity_Id := Defining_Entity (N);
1094 Orig_Decl : constant Node_Id := Original_Node (Parent (N));
1095 Vis_Decls : constant List_Id := Visible_Declarations (N);
1096 Priv_Decls : constant List_Id := Private_Declarations (N);
1099 Public_Child : Boolean;
1101 Private_With_Clauses_Installed : Boolean := False;
1102 -- In Ada 2005, private with_clauses are visible in the private part
1103 -- of a nested package, even if it appears in the public part of the
1104 -- enclosing package. This requires a separate step to install these
1105 -- private_with_clauses, and remove them at the end of the nested
1108 procedure Check_One_Tagged_Type_Or_Extension_At_Most;
1109 -- Issue an error in SPARK mode if a package specification contains
1110 -- more than one tagged type or type extension.
1112 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id);
1113 -- Clears constant indications (Never_Set_In_Source, Constant_Value, and
1114 -- Is_True_Constant) on all variables that are entities of Id, and on
1115 -- the chain whose first element is FE. A recursive call is made for all
1116 -- packages and generic packages.
1118 procedure Generate_Parent_References;
1119 -- For a child unit, generate references to parent units, for
1120 -- GPS navigation purposes.
1122 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean;
1123 -- Child and Unit are entities of compilation units. True if Child
1124 -- is a public child of Parent as defined in 10.1.1
1126 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id);
1127 -- Reject completion of an incomplete or private type declarations
1128 -- having a known discriminant part by an unchecked union.
1130 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id);
1131 -- Given the package entity of a generic package instantiation or
1132 -- formal package whose corresponding generic is a child unit, installs
1133 -- the private declarations of each of the child unit's parents.
1134 -- This has to be done at the point of entering the instance package's
1135 -- private part rather than being done in Sem_Ch12.Install_Parent
1136 -- (which is where the parents' visible declarations are installed).
1138 ------------------------------------------------
1139 -- Check_One_Tagged_Type_Or_Extension_At_Most --
1140 ------------------------------------------------
1142 procedure Check_One_Tagged_Type_Or_Extension_At_Most is
1145 procedure Check_Decls (Decls : List_Id);
1146 -- Check that either Previous is Empty and Decls does not contain
1147 -- more than one tagged type or type extension, or Previous is
1148 -- already set and Decls contains no tagged type or type extension.
1154 procedure Check_Decls (Decls : List_Id) is
1158 Decl := First (Decls);
1159 while Present (Decl) loop
1160 if Nkind (Decl) = N_Full_Type_Declaration
1161 and then Is_Tagged_Type (Defining_Identifier (Decl))
1163 if No (Previous) then
1167 Error_Msg_Sloc := Sloc (Previous);
1168 Check_SPARK_05_Restriction
1169 ("at most one tagged type or type extension allowed",
1170 "\\ previous declaration#",
1179 -- Start of processing for Check_One_Tagged_Type_Or_Extension_At_Most
1183 Check_Decls (Vis_Decls);
1185 if Present (Priv_Decls) then
1186 Check_Decls (Priv_Decls);
1188 end Check_One_Tagged_Type_Or_Extension_At_Most;
1190 ---------------------
1191 -- Clear_Constants --
1192 ---------------------
1194 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id) is
1198 -- Ignore package renamings, not interesting and they can cause self
1199 -- referential loops in the code below.
1201 if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then
1205 -- Note: in the loop below, the check for Next_Entity pointing back
1206 -- to the package entity may seem odd, but it is needed, because a
1207 -- package can contain a renaming declaration to itself, and such
1208 -- renamings are generated automatically within package instances.
1211 while Present (E) and then E /= Id loop
1212 if Is_Assignable (E) then
1213 Set_Never_Set_In_Source (E, False);
1214 Set_Is_True_Constant (E, False);
1215 Set_Current_Value (E, Empty);
1216 Set_Is_Known_Null (E, False);
1217 Set_Last_Assignment (E, Empty);
1219 if not Can_Never_Be_Null (E) then
1220 Set_Is_Known_Non_Null (E, False);
1223 elsif Is_Package_Or_Generic_Package (E) then
1224 Clear_Constants (E, First_Entity (E));
1225 Clear_Constants (E, First_Private_Entity (E));
1230 end Clear_Constants;
1232 --------------------------------
1233 -- Generate_Parent_References --
1234 --------------------------------
1236 procedure Generate_Parent_References is
1237 Decl : constant Node_Id := Parent (N);
1240 if Id = Cunit_Entity (Main_Unit)
1241 or else Parent (Decl) = Library_Unit (Cunit (Main_Unit))
1243 Generate_Reference (Id, Scope (Id), 'k', False);
1245 elsif not Nkind_In (Unit (Cunit (Main_Unit)), N_Subprogram_Body,
1248 -- If current unit is an ancestor of main unit, generate a
1249 -- reference to its own parent.
1253 Main_Spec : Node_Id := Unit (Cunit (Main_Unit));
1256 if Nkind (Main_Spec) = N_Package_Body then
1257 Main_Spec := Unit (Library_Unit (Cunit (Main_Unit)));
1260 U := Parent_Spec (Main_Spec);
1261 while Present (U) loop
1262 if U = Parent (Decl) then
1263 Generate_Reference (Id, Scope (Id), 'k', False);
1266 elsif Nkind (Unit (U)) = N_Package_Body then
1270 U := Parent_Spec (Unit (U));
1275 end Generate_Parent_References;
1277 ---------------------
1278 -- Is_Public_Child --
1279 ---------------------
1281 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean is
1283 if not Is_Private_Descendant (Child) then
1286 if Child = Unit then
1287 return not Private_Present (
1288 Parent (Unit_Declaration_Node (Child)));
1290 return Is_Public_Child (Scope (Child), Unit);
1293 end Is_Public_Child;
1295 ----------------------------------------
1296 -- Inspect_Unchecked_Union_Completion --
1297 ----------------------------------------
1299 procedure Inspect_Unchecked_Union_Completion (Decls : List_Id) is
1303 Decl := First (Decls);
1304 while Present (Decl) loop
1306 -- We are looking at an incomplete or private type declaration
1307 -- with a known_discriminant_part whose full view is an
1310 if Nkind_In (Decl, N_Incomplete_Type_Declaration,
1311 N_Private_Type_Declaration)
1312 and then Has_Discriminants (Defining_Identifier (Decl))
1313 and then Present (Full_View (Defining_Identifier (Decl)))
1315 Is_Unchecked_Union (Full_View (Defining_Identifier (Decl)))
1318 ("completion of discriminated partial view "
1319 & "cannot be an unchecked union",
1320 Full_View (Defining_Identifier (Decl)));
1325 end Inspect_Unchecked_Union_Completion;
1327 -----------------------------------------
1328 -- Install_Parent_Private_Declarations --
1329 -----------------------------------------
1331 procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id) is
1332 Inst_Par : Entity_Id;
1333 Gen_Par : Entity_Id;
1334 Inst_Node : Node_Id;
1337 Inst_Par := Inst_Id;
1340 Generic_Parent (Specification (Unit_Declaration_Node (Inst_Par)));
1341 while Present (Gen_Par) and then Is_Child_Unit (Gen_Par) loop
1342 Inst_Node := Get_Package_Instantiation_Node (Inst_Par);
1344 if Nkind_In (Inst_Node, N_Package_Instantiation,
1345 N_Formal_Package_Declaration)
1346 and then Nkind (Name (Inst_Node)) = N_Expanded_Name
1348 Inst_Par := Entity (Prefix (Name (Inst_Node)));
1350 if Present (Renamed_Entity (Inst_Par)) then
1351 Inst_Par := Renamed_Entity (Inst_Par);
1356 (Specification (Unit_Declaration_Node (Inst_Par)));
1358 -- Install the private declarations and private use clauses
1359 -- of a parent instance of the child instance, unless the
1360 -- parent instance private declarations have already been
1361 -- installed earlier in Analyze_Package_Specification, which
1362 -- happens when a generic child is instantiated, and the
1363 -- instance is a child of the parent instance.
1365 -- Installing the use clauses of the parent instance twice
1366 -- is both unnecessary and wrong, because it would cause the
1367 -- clauses to be chained to themselves in the use clauses
1368 -- list of the scope stack entry. That in turn would cause
1369 -- an endless loop from End_Use_Clauses upon scope exit.
1371 -- The parent is now fully visible. It may be a hidden open
1372 -- scope if we are currently compiling some child instance
1373 -- declared within it, but while the current instance is being
1374 -- compiled the parent is immediately visible. In particular
1375 -- its entities must remain visible if a stack save/restore
1376 -- takes place through a call to Rtsfind.
1378 if Present (Gen_Par) then
1379 if not In_Private_Part (Inst_Par) then
1380 Install_Private_Declarations (Inst_Par);
1381 Set_Use (Private_Declarations
1383 (Unit_Declaration_Node (Inst_Par))));
1384 Set_Is_Hidden_Open_Scope (Inst_Par, False);
1387 -- If we've reached the end of the generic instance parents,
1388 -- then finish off by looping through the nongeneric parents
1389 -- and installing their private declarations.
1391 -- If one of the non-generic parents is itself on the scope
1392 -- stack, do not install its private declarations: they are
1393 -- installed in due time when the private part of that parent
1394 -- is analyzed. This is delicate ???
1397 while Present (Inst_Par)
1398 and then Inst_Par /= Standard_Standard
1399 and then (not In_Open_Scopes (Inst_Par)
1400 or else not In_Private_Part (Inst_Par))
1402 Install_Private_Declarations (Inst_Par);
1403 Set_Use (Private_Declarations
1405 (Unit_Declaration_Node (Inst_Par))));
1406 Inst_Par := Scope (Inst_Par);
1416 end Install_Parent_Private_Declarations;
1418 -- Start of processing for Analyze_Package_Specification
1421 if Present (Vis_Decls) then
1422 Analyze_Declarations (Vis_Decls);
1425 -- Inspect the entities defined in the package and ensure that all
1426 -- incomplete types have received full declarations. Build default
1427 -- initial condition and invariant procedures for all qualifying types.
1429 E := First_Entity (Id);
1430 while Present (E) loop
1432 -- Check on incomplete types
1434 -- AI05-0213: A formal incomplete type has no completion
1436 if Ekind (E) = E_Incomplete_Type
1437 and then No (Full_View (E))
1438 and then not Is_Generic_Type (E)
1440 Error_Msg_N ("no declaration in visible part for incomplete}", E);
1445 -- Each private type subject to pragma Default_Initial_Condition
1446 -- declares a specialized procedure which verifies the assumption
1447 -- of the pragma. The declaration appears in the visible part of
1448 -- the package to allow for being called from the outside.
1450 if Has_Default_Init_Cond (E) then
1451 Build_Default_Init_Cond_Procedure_Declaration (E);
1453 -- A private extension inherits the default initial condition
1454 -- procedure from its parent type.
1456 elsif Has_Inherited_Default_Init_Cond (E) then
1457 Inherit_Default_Init_Cond_Procedure (E);
1460 -- If invariants are present, build the invariant procedure for a
1461 -- private type, but not any of its subtypes or interface types.
1463 if Has_Invariants (E) then
1464 if Ekind (E) = E_Private_Subtype then
1467 Build_Invariant_Procedure (E, N);
1475 if Is_Remote_Call_Interface (Id)
1476 and then Nkind (Parent (Parent (N))) = N_Compilation_Unit
1478 Validate_RCI_Declarations (Id);
1481 -- Save global references in the visible declarations, before installing
1482 -- private declarations of parent unit if there is one, because the
1483 -- privacy status of types defined in the parent will change. This is
1484 -- only relevant for generic child units, but is done in all cases for
1487 if Ekind (Id) = E_Generic_Package
1488 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1491 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1492 Save_Priv : constant List_Id := Private_Declarations (Orig_Spec);
1494 Set_Private_Declarations (Orig_Spec, Empty_List);
1495 Save_Global_References (Orig_Decl);
1496 Set_Private_Declarations (Orig_Spec, Save_Priv);
1500 -- If package is a public child unit, then make the private declarations
1501 -- of the parent visible.
1503 Public_Child := False;
1507 Pack_Decl : Node_Id;
1512 Par_Spec := Parent_Spec (Parent (N));
1514 -- If the package is formal package of an enclosing generic, it is
1515 -- transformed into a local generic declaration, and compiled to make
1516 -- its spec available. We need to retrieve the original generic to
1517 -- determine whether it is a child unit, and install its parents.
1521 Nkind (Original_Node (Parent (N))) = N_Formal_Package_Declaration
1523 Par := Entity (Name (Original_Node (Parent (N))));
1524 Par_Spec := Parent_Spec (Unit_Declaration_Node (Par));
1527 if Present (Par_Spec) then
1528 Generate_Parent_References;
1530 while Scope (Par) /= Standard_Standard
1531 and then Is_Public_Child (Id, Par)
1532 and then In_Open_Scopes (Par)
1534 Public_Child := True;
1536 Install_Private_Declarations (Par);
1537 Install_Private_With_Clauses (Par);
1538 Pack_Decl := Unit_Declaration_Node (Par);
1539 Set_Use (Private_Declarations (Specification (Pack_Decl)));
1544 if Is_Compilation_Unit (Id) then
1545 Install_Private_With_Clauses (Id);
1548 -- The current compilation unit may include private with_clauses,
1549 -- which are visible in the private part of the current nested
1550 -- package, and have to be installed now. This is not done for
1551 -- nested instantiations, where the private with_clauses of the
1552 -- enclosing unit have no effect once the instantiation info is
1553 -- established and we start analyzing the package declaration.
1556 Comp_Unit : constant Entity_Id := Cunit_Entity (Current_Sem_Unit);
1558 if Is_Package_Or_Generic_Package (Comp_Unit)
1559 and then not In_Private_Part (Comp_Unit)
1560 and then not In_Instance
1562 Install_Private_With_Clauses (Comp_Unit);
1563 Private_With_Clauses_Installed := True;
1568 -- If this is a package associated with a generic instance or formal
1569 -- package, then the private declarations of each of the generic's
1570 -- parents must be installed at this point.
1572 if Is_Generic_Instance (Id) then
1573 Install_Parent_Private_Declarations (Id);
1576 -- Analyze private part if present. The flag In_Private_Part is reset
1577 -- in End_Package_Scope.
1579 L := Last_Entity (Id);
1581 if Present (Priv_Decls) then
1582 Set_In_Private_Part (Id);
1584 -- Upon entering a public child's private part, it may be necessary
1585 -- to declare subprograms that were derived in the package's visible
1586 -- part but not yet made visible.
1588 if Public_Child then
1589 Declare_Inherited_Private_Subprograms (Id);
1592 Analyze_Declarations (Priv_Decls);
1594 -- Check the private declarations for incomplete deferred constants
1596 Inspect_Deferred_Constant_Completion (Priv_Decls);
1598 -- The first private entity is the immediate follower of the last
1599 -- visible entity, if there was one.
1602 Set_First_Private_Entity (Id, Next_Entity (L));
1604 Set_First_Private_Entity (Id, First_Entity (Id));
1607 -- There may be inherited private subprograms that need to be declared,
1608 -- even in the absence of an explicit private part. If there are any
1609 -- public declarations in the package and the package is a public child
1610 -- unit, then an implicit private part is assumed.
1612 elsif Present (L) and then Public_Child then
1613 Set_In_Private_Part (Id);
1614 Declare_Inherited_Private_Subprograms (Id);
1615 Set_First_Private_Entity (Id, Next_Entity (L));
1618 E := First_Entity (Id);
1619 while Present (E) loop
1621 -- Check rule of 3.6(11), which in general requires waiting till all
1622 -- full types have been seen.
1624 if Ekind (E) = E_Record_Type or else Ekind (E) = E_Array_Type then
1625 Check_Aliased_Component_Types (E);
1628 -- Check preelaborable initialization for full type completing a
1629 -- private type for which pragma Preelaborable_Initialization given.
1632 and then Must_Have_Preelab_Init (E)
1633 and then not Has_Preelaborable_Initialization (E)
1636 ("full view of & does not have preelaborable initialization", E);
1639 -- An invariant may appear on a full view of a type
1642 and then Has_Private_Declaration (E)
1643 and then Nkind (Parent (E)) = N_Full_Type_Declaration
1646 IP_Built : Boolean := False;
1649 if Has_Aspects (Parent (E)) then
1654 ASN := First (Aspect_Specifications (Parent (E)));
1655 while Present (ASN) loop
1656 if Nam_In (Chars (Identifier (ASN)),
1658 Name_Type_Invariant)
1660 Build_Invariant_Procedure (E, N);
1670 -- Invariants may have been inherited from progenitors
1673 and then Has_Interfaces (E)
1674 and then Has_Inheritable_Invariants (E)
1675 and then not Is_Interface (E)
1676 and then not Is_Class_Wide_Type (E)
1678 Build_Invariant_Procedure (E, N);
1686 -- Ada 2005 (AI-216): The completion of an incomplete or private type
1687 -- declaration having a known_discriminant_part shall not be an
1688 -- unchecked union type.
1690 if Present (Vis_Decls) then
1691 Inspect_Unchecked_Union_Completion (Vis_Decls);
1694 if Present (Priv_Decls) then
1695 Inspect_Unchecked_Union_Completion (Priv_Decls);
1698 if Ekind (Id) = E_Generic_Package
1699 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
1700 and then Present (Priv_Decls)
1702 -- Save global references in private declarations, ignoring the
1703 -- visible declarations that were processed earlier.
1706 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
1707 Save_Vis : constant List_Id := Visible_Declarations (Orig_Spec);
1708 Save_Form : constant List_Id :=
1709 Generic_Formal_Declarations (Orig_Decl);
1712 Set_Visible_Declarations (Orig_Spec, Empty_List);
1713 Set_Generic_Formal_Declarations (Orig_Decl, Empty_List);
1714 Save_Global_References (Orig_Decl);
1715 Set_Generic_Formal_Declarations (Orig_Decl, Save_Form);
1716 Set_Visible_Declarations (Orig_Spec, Save_Vis);
1720 Process_End_Label (N, 'e', Id);
1722 -- Remove private_with_clauses of enclosing compilation unit, if they
1725 if Private_With_Clauses_Installed then
1726 Remove_Private_With_Clauses (Cunit (Current_Sem_Unit));
1729 -- For the case of a library level package, we must go through all the
1730 -- entities clearing the indications that the value may be constant and
1731 -- not modified. Why? Because any client of this package may modify
1732 -- these values freely from anywhere. This also applies to any nested
1733 -- packages or generic packages.
1735 -- For now we unconditionally clear constants for packages that are
1736 -- instances of generic packages. The reason is that we do not have the
1737 -- body yet, and we otherwise think things are unreferenced when they
1738 -- are not. This should be fixed sometime (the effect is not terrible,
1739 -- we just lose some warnings, and also some cases of value propagation)
1742 if Is_Library_Level_Entity (Id)
1743 or else Is_Generic_Instance (Id)
1745 Clear_Constants (Id, First_Entity (Id));
1746 Clear_Constants (Id, First_Private_Entity (Id));
1749 -- Issue an error in SPARK mode if a package specification contains
1750 -- more than one tagged type or type extension.
1752 Check_One_Tagged_Type_Or_Extension_At_Most;
1754 -- If switch set, output information on why body required
1756 if List_Body_Required_Info
1757 and then In_Extended_Main_Source_Unit (Id)
1758 and then Unit_Requires_Body (Id)
1760 Unit_Requires_Body_Info (Id);
1762 end Analyze_Package_Specification;
1764 --------------------------------------
1765 -- Analyze_Private_Type_Declaration --
1766 --------------------------------------
1768 procedure Analyze_Private_Type_Declaration (N : Node_Id) is
1769 Id : constant Entity_Id := Defining_Identifier (N);
1770 PF : constant Boolean := Is_Pure (Enclosing_Lib_Unit_Entity);
1773 Generate_Definition (Id);
1774 Set_Is_Pure (Id, PF);
1775 Init_Size_Align (Id);
1777 if not Is_Package_Or_Generic_Package (Current_Scope)
1778 or else In_Private_Part (Current_Scope)
1780 Error_Msg_N ("invalid context for private declaration", N);
1783 New_Private_Type (N, Id, N);
1784 Set_Depends_On_Private (Id);
1786 -- A type declared within a Ghost region is automatically Ghost
1787 -- (SPARK RM 6.9(2)).
1789 if Ghost_Mode > None then
1790 Set_Is_Ghost_Entity (Id);
1793 if Has_Aspects (N) then
1794 Analyze_Aspect_Specifications (N, Id);
1796 end Analyze_Private_Type_Declaration;
1798 ----------------------------------
1799 -- Check_Anonymous_Access_Types --
1800 ----------------------------------
1802 procedure Check_Anonymous_Access_Types
1803 (Spec_Id : Entity_Id;
1810 -- Itype references are only needed by gigi, to force elaboration of
1811 -- itypes. In the absence of code generation, they are not needed.
1813 if not Expander_Active then
1817 E := First_Entity (Spec_Id);
1818 while Present (E) loop
1819 if Ekind (E) = E_Anonymous_Access_Type
1820 and then From_Limited_With (E)
1822 IR := Make_Itype_Reference (Sloc (P_Body));
1825 if No (Declarations (P_Body)) then
1826 Set_Declarations (P_Body, New_List (IR));
1828 Prepend (IR, Declarations (P_Body));
1834 end Check_Anonymous_Access_Types;
1836 -------------------------------------------
1837 -- Declare_Inherited_Private_Subprograms --
1838 -------------------------------------------
1840 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id) is
1842 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean;
1843 -- Check whether an inherited subprogram S is an operation of an
1844 -- untagged derived type T.
1846 ---------------------
1847 -- Is_Primitive_Of --
1848 ---------------------
1850 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean is
1854 -- If the full view is a scalar type, the type is the anonymous base
1855 -- type, but the operation mentions the first subtype, so check the
1856 -- signature against the base type.
1858 if Base_Type (Etype (S)) = Base_Type (T) then
1862 Formal := First_Formal (S);
1863 while Present (Formal) loop
1864 if Base_Type (Etype (Formal)) = Base_Type (T) then
1868 Next_Formal (Formal);
1873 end Is_Primitive_Of;
1880 Op_Elmt_2 : Elmt_Id;
1881 Prim_Op : Entity_Id;
1882 New_Op : Entity_Id := Empty;
1883 Parent_Subp : Entity_Id;
1886 -- Start of processing for Declare_Inherited_Private_Subprograms
1889 E := First_Entity (Id);
1890 while Present (E) loop
1892 -- If the entity is a nonprivate type extension whose parent type
1893 -- is declared in an open scope, then the type may have inherited
1894 -- operations that now need to be made visible. Ditto if the entity
1895 -- is a formal derived type in a child unit.
1897 if ((Is_Derived_Type (E) and then not Is_Private_Type (E))
1899 (Nkind (Parent (E)) = N_Private_Extension_Declaration
1900 and then Is_Generic_Type (E)))
1901 and then In_Open_Scopes (Scope (Etype (E)))
1902 and then Is_Base_Type (E)
1904 if Is_Tagged_Type (E) then
1905 Op_List := Primitive_Operations (E);
1907 Tag := First_Tag_Component (E);
1909 Op_Elmt := First_Elmt (Op_List);
1910 while Present (Op_Elmt) loop
1911 Prim_Op := Node (Op_Elmt);
1913 -- Search primitives that are implicit operations with an
1914 -- internal name whose parent operation has a normal name.
1916 if Present (Alias (Prim_Op))
1917 and then Find_Dispatching_Type (Alias (Prim_Op)) /= E
1918 and then not Comes_From_Source (Prim_Op)
1919 and then Is_Internal_Name (Chars (Prim_Op))
1920 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
1922 Parent_Subp := Alias (Prim_Op);
1924 -- Case 1: Check if the type has also an explicit
1925 -- overriding for this primitive.
1927 Op_Elmt_2 := Next_Elmt (Op_Elmt);
1928 while Present (Op_Elmt_2) loop
1930 -- Skip entities with attribute Interface_Alias since
1931 -- they are not overriding primitives (these entities
1932 -- link an interface primitive with their covering
1935 if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp)
1936 and then Type_Conformant (Prim_Op, Node (Op_Elmt_2))
1937 and then No (Interface_Alias (Node (Op_Elmt_2)))
1939 -- The private inherited operation has been
1940 -- overridden by an explicit subprogram:
1941 -- replace the former by the latter.
1943 New_Op := Node (Op_Elmt_2);
1944 Replace_Elmt (Op_Elmt, New_Op);
1945 Remove_Elmt (Op_List, Op_Elmt_2);
1946 Set_Overridden_Operation (New_Op, Parent_Subp);
1948 -- We don't need to inherit its dispatching slot.
1949 -- Set_All_DT_Position has previously ensured that
1950 -- the same slot was assigned to the two primitives
1953 and then Present (DTC_Entity (New_Op))
1954 and then Present (DTC_Entity (Prim_Op))
1957 (DT_Position (New_Op) = DT_Position (Prim_Op));
1961 goto Next_Primitive;
1964 Next_Elmt (Op_Elmt_2);
1967 -- Case 2: We have not found any explicit overriding and
1968 -- hence we need to declare the operation (i.e., make it
1971 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
1973 -- Inherit the dispatching slot if E is already frozen
1976 and then Present (DTC_Entity (Alias (Prim_Op)))
1978 Set_DTC_Entity_Value (E, New_Op);
1979 Set_DT_Position_Value (New_Op,
1980 DT_Position (Alias (Prim_Op)));
1984 (Is_Dispatching_Operation (New_Op)
1985 and then Node (Last_Elmt (Op_List)) = New_Op);
1987 -- Substitute the new operation for the old one in the
1988 -- type's primitive operations list. Since the new
1989 -- operation was also just added to the end of list,
1990 -- the last element must be removed.
1992 -- (Question: is there a simpler way of declaring the
1993 -- operation, say by just replacing the name of the
1994 -- earlier operation, reentering it in the in the symbol
1995 -- table (how?), and marking it as private???)
1997 Replace_Elmt (Op_Elmt, New_Op);
1998 Remove_Last_Elmt (Op_List);
2002 Next_Elmt (Op_Elmt);
2005 -- Generate listing showing the contents of the dispatch table
2007 if Debug_Flag_ZZ then
2012 -- For untagged type, scan forward to locate inherited hidden
2015 Prim_Op := Next_Entity (E);
2016 while Present (Prim_Op) loop
2017 if Is_Subprogram (Prim_Op)
2018 and then Present (Alias (Prim_Op))
2019 and then not Comes_From_Source (Prim_Op)
2020 and then Is_Internal_Name (Chars (Prim_Op))
2021 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
2022 and then Is_Primitive_Of (E, Prim_Op)
2024 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
2027 Next_Entity (Prim_Op);
2029 -- Derived operations appear immediately after the type
2030 -- declaration (or the following subtype indication for
2031 -- a derived scalar type). Further declarations cannot
2032 -- include inherited operations of the type.
2034 if Present (Prim_Op) then
2035 exit when Ekind (Prim_Op) not in Overloadable_Kind;
2043 end Declare_Inherited_Private_Subprograms;
2045 -----------------------
2046 -- End_Package_Scope --
2047 -----------------------
2049 procedure End_Package_Scope (P : Entity_Id) is
2051 Uninstall_Declarations (P);
2053 end End_Package_Scope;
2055 ---------------------------
2056 -- Exchange_Declarations --
2057 ---------------------------
2059 procedure Exchange_Declarations (Id : Entity_Id) is
2060 Full_Id : constant Entity_Id := Full_View (Id);
2061 H1 : constant Entity_Id := Homonym (Id);
2062 Next1 : constant Entity_Id := Next_Entity (Id);
2067 -- If missing full declaration for type, nothing to exchange
2069 if No (Full_Id) then
2073 -- Otherwise complete the exchange, and preserve semantic links
2075 Next2 := Next_Entity (Full_Id);
2076 H2 := Homonym (Full_Id);
2078 -- Reset full declaration pointer to reflect the switched entities and
2079 -- readjust the next entity chains.
2081 Exchange_Entities (Id, Full_Id);
2083 Set_Next_Entity (Id, Next1);
2084 Set_Homonym (Id, H1);
2086 Set_Full_View (Full_Id, Id);
2087 Set_Next_Entity (Full_Id, Next2);
2088 Set_Homonym (Full_Id, H2);
2089 end Exchange_Declarations;
2091 ----------------------------
2092 -- Install_Package_Entity --
2093 ----------------------------
2095 procedure Install_Package_Entity (Id : Entity_Id) is
2097 if not Is_Internal (Id) then
2098 if Debug_Flag_E then
2099 Write_Str ("Install: ");
2100 Write_Name (Chars (Id));
2104 if Is_Child_Unit (Id) then
2107 -- Do not enter implicitly inherited non-overridden subprograms of
2108 -- a tagged type back into visibility if they have non-conformant
2109 -- homographs (Ada RM 8.3 12.3/2).
2111 elsif Is_Hidden_Non_Overridden_Subpgm (Id) then
2115 Set_Is_Immediately_Visible (Id);
2118 end Install_Package_Entity;
2120 ----------------------------------
2121 -- Install_Private_Declarations --
2122 ----------------------------------
2124 procedure Install_Private_Declarations (P : Entity_Id) is
2127 Priv_Deps : Elist_Id;
2129 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id);
2130 -- When the full view of a private type is made available, we do the
2131 -- same for its private dependents under proper visibility conditions.
2132 -- When compiling a grand-chid unit this needs to be done recursively.
2134 -----------------------------
2135 -- Swap_Private_Dependents --
2136 -----------------------------
2138 procedure Swap_Private_Dependents (Priv_Deps : Elist_Id) is
2141 Priv_Elmt : Elmt_Id;
2145 Priv_Elmt := First_Elmt (Priv_Deps);
2146 while Present (Priv_Elmt) loop
2147 Priv := Node (Priv_Elmt);
2149 -- Before the exchange, verify that the presence of the Full_View
2150 -- field. This field will be empty if the entity has already been
2151 -- installed due to a previous call.
2153 if Present (Full_View (Priv)) and then Is_Visible_Dependent (Priv)
2155 if Is_Private_Type (Priv) then
2156 Deps := Private_Dependents (Priv);
2162 -- For each subtype that is swapped, we also swap the reference
2163 -- to it in Private_Dependents, to allow access to it when we
2164 -- swap them out in End_Package_Scope.
2166 Replace_Elmt (Priv_Elmt, Full_View (Priv));
2168 -- Ensure that both views of the dependent private subtype are
2169 -- immediately visible if within some open scope. Check full
2170 -- view before exchanging views.
2172 if In_Open_Scopes (Scope (Full_View (Priv))) then
2173 Set_Is_Immediately_Visible (Priv);
2176 Exchange_Declarations (Priv);
2177 Set_Is_Immediately_Visible
2178 (Priv, In_Open_Scopes (Scope (Priv)));
2180 Set_Is_Potentially_Use_Visible
2181 (Priv, Is_Potentially_Use_Visible (Node (Priv_Elmt)));
2183 -- Within a child unit, recurse, except in generic child unit,
2184 -- which (unfortunately) handle private_dependents separately.
2187 and then Is_Child_Unit (Cunit_Entity (Current_Sem_Unit))
2188 and then not Is_Empty_Elmt_List (Deps)
2189 and then not Inside_A_Generic
2191 Swap_Private_Dependents (Deps);
2195 Next_Elmt (Priv_Elmt);
2197 end Swap_Private_Dependents;
2199 -- Start of processing for Install_Private_Declarations
2202 -- First exchange declarations for private types, so that the full
2203 -- declaration is visible. For each private type, we check its
2204 -- Private_Dependents list and also exchange any subtypes of or derived
2205 -- types from it. Finally, if this is a Taft amendment type, the
2206 -- incomplete declaration is irrelevant, and we want to link the
2207 -- eventual full declaration with the original private one so we
2208 -- also skip the exchange.
2210 Id := First_Entity (P);
2211 while Present (Id) and then Id /= First_Private_Entity (P) loop
2212 if Is_Private_Base_Type (Id)
2213 and then Present (Full_View (Id))
2214 and then Comes_From_Source (Full_View (Id))
2215 and then Scope (Full_View (Id)) = Scope (Id)
2216 and then Ekind (Full_View (Id)) /= E_Incomplete_Type
2218 -- If there is a use-type clause on the private type, set the full
2219 -- view accordingly.
2221 Set_In_Use (Full_View (Id), In_Use (Id));
2222 Full := Full_View (Id);
2224 if Is_Private_Base_Type (Full)
2225 and then Has_Private_Declaration (Full)
2226 and then Nkind (Parent (Full)) = N_Full_Type_Declaration
2227 and then In_Open_Scopes (Scope (Etype (Full)))
2228 and then In_Package_Body (Current_Scope)
2229 and then not Is_Private_Type (Etype (Full))
2231 -- This is the completion of a private type by a derivation
2232 -- from another private type which is not private anymore. This
2233 -- can only happen in a package nested within a child package,
2234 -- when the parent type is defined in the parent unit. At this
2235 -- point the current type is not private either, and we have
2236 -- to install the underlying full view, which is now visible.
2237 -- Save the current full view as well, so that all views can be
2238 -- restored on exit. It may seem that after compiling the child
2239 -- body there are not environments to restore, but the back-end
2240 -- expects those links to be valid, and freeze nodes depend on
2243 if No (Full_View (Full))
2244 and then Present (Underlying_Full_View (Full))
2246 Set_Full_View (Id, Underlying_Full_View (Full));
2247 Set_Underlying_Full_View (Id, Full);
2249 Set_Underlying_Full_View (Full, Empty);
2250 Set_Is_Frozen (Full_View (Id));
2254 Priv_Deps := Private_Dependents (Id);
2255 Exchange_Declarations (Id);
2256 Set_Is_Immediately_Visible (Id);
2257 Swap_Private_Dependents (Priv_Deps);
2263 -- Next make other declarations in the private part visible as well
2265 Id := First_Private_Entity (P);
2266 while Present (Id) loop
2267 Install_Package_Entity (Id);
2268 Set_Is_Hidden (Id, False);
2272 -- Indicate that the private part is currently visible, so it can be
2273 -- properly reset on exit.
2275 Set_In_Private_Part (P);
2276 end Install_Private_Declarations;
2278 ----------------------------------
2279 -- Install_Visible_Declarations --
2280 ----------------------------------
2282 procedure Install_Visible_Declarations (P : Entity_Id) is
2284 Last_Entity : Entity_Id;
2288 (Is_Package_Or_Generic_Package (P) or else Is_Record_Type (P));
2290 if Is_Package_Or_Generic_Package (P) then
2291 Last_Entity := First_Private_Entity (P);
2293 Last_Entity := Empty;
2296 Id := First_Entity (P);
2297 while Present (Id) and then Id /= Last_Entity loop
2298 Install_Package_Entity (Id);
2301 end Install_Visible_Declarations;
2303 --------------------------
2304 -- Is_Private_Base_Type --
2305 --------------------------
2307 function Is_Private_Base_Type (E : Entity_Id) return Boolean is
2309 return Ekind (E) = E_Private_Type
2310 or else Ekind (E) = E_Limited_Private_Type
2311 or else Ekind (E) = E_Record_Type_With_Private;
2312 end Is_Private_Base_Type;
2314 --------------------------
2315 -- Is_Visible_Dependent --
2316 --------------------------
2318 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean
2320 S : constant Entity_Id := Scope (Dep);
2323 -- Renamings created for actual types have the visibility of the actual
2325 if Ekind (S) = E_Package
2326 and then Is_Generic_Instance (S)
2327 and then (Is_Generic_Actual_Type (Dep)
2328 or else Is_Generic_Actual_Type (Full_View (Dep)))
2332 elsif not (Is_Derived_Type (Dep))
2333 and then Is_Derived_Type (Full_View (Dep))
2335 -- When instantiating a package body, the scope stack is empty, so
2336 -- check instead whether the dependent type is defined in the same
2337 -- scope as the instance itself.
2339 return In_Open_Scopes (S)
2340 or else (Is_Generic_Instance (Current_Scope)
2341 and then Scope (Dep) = Scope (Current_Scope));
2345 end Is_Visible_Dependent;
2347 ----------------------------
2348 -- May_Need_Implicit_Body --
2349 ----------------------------
2351 procedure May_Need_Implicit_Body (E : Entity_Id) is
2352 P : constant Node_Id := Unit_Declaration_Node (E);
2353 S : constant Node_Id := Parent (P);
2358 if not Has_Completion (E)
2359 and then Nkind (P) = N_Package_Declaration
2360 and then (Present (Activation_Chain_Entity (P)) or else Has_RACW (E))
2363 Make_Package_Body (Sloc (E),
2364 Defining_Unit_Name => Make_Defining_Identifier (Sloc (E),
2365 Chars => Chars (E)),
2366 Declarations => New_List);
2368 if Nkind (S) = N_Package_Specification then
2369 if Present (Private_Declarations (S)) then
2370 Decls := Private_Declarations (S);
2372 Decls := Visible_Declarations (S);
2375 Decls := Declarations (S);
2381 end May_Need_Implicit_Body;
2383 ----------------------
2384 -- New_Private_Type --
2385 ----------------------
2387 procedure New_Private_Type (N : Node_Id; Id : Entity_Id; Def : Node_Id) is
2389 -- For other than Ada 2012, enter the name in the current scope
2391 if Ada_Version < Ada_2012 then
2394 -- Ada 2012 (AI05-0162): Enter the name in the current scope. Note that
2395 -- there may be an incomplete previous view.
2401 Prev := Find_Type_Name (N);
2402 pragma Assert (Prev = Id
2403 or else (Ekind (Prev) = E_Incomplete_Type
2404 and then Present (Full_View (Prev))
2405 and then Full_View (Prev) = Id));
2409 if Limited_Present (Def) then
2410 Set_Ekind (Id, E_Limited_Private_Type);
2412 Set_Ekind (Id, E_Private_Type);
2416 Set_Has_Delayed_Freeze (Id);
2417 Set_Is_First_Subtype (Id);
2418 Init_Size_Align (Id);
2420 Set_Is_Constrained (Id,
2421 No (Discriminant_Specifications (N))
2422 and then not Unknown_Discriminants_Present (N));
2424 -- Set tagged flag before processing discriminants, to catch illegal
2427 Set_Is_Tagged_Type (Id, Tagged_Present (Def));
2429 Set_Discriminant_Constraint (Id, No_Elist);
2430 Set_Stored_Constraint (Id, No_Elist);
2432 if Present (Discriminant_Specifications (N)) then
2434 Process_Discriminants (N);
2437 elsif Unknown_Discriminants_Present (N) then
2438 Set_Has_Unknown_Discriminants (Id);
2441 Set_Private_Dependents (Id, New_Elmt_List);
2443 if Tagged_Present (Def) then
2444 Set_Ekind (Id, E_Record_Type_With_Private);
2445 Set_Direct_Primitive_Operations (Id, New_Elmt_List);
2446 Set_Is_Abstract_Type (Id, Abstract_Present (Def));
2447 Set_Is_Limited_Record (Id, Limited_Present (Def));
2448 Set_Has_Delayed_Freeze (Id, True);
2450 -- Recognize Ada.Real_Time.Timing_Events.Timing_Events here
2452 if Is_RTE (Id, RE_Timing_Event) then
2453 Set_Has_Timing_Event (Id);
2456 -- Create a class-wide type with the same attributes
2458 Make_Class_Wide_Type (Id);
2460 elsif Abstract_Present (Def) then
2461 Error_Msg_N ("only a tagged type can be abstract", N);
2463 end New_Private_Type;
2465 ---------------------------------
2466 -- Requires_Completion_In_Body --
2467 ---------------------------------
2469 function Requires_Completion_In_Body
2471 Pack_Id : Entity_Id;
2472 Do_Abstract_States : Boolean := False) return Boolean
2475 -- Always ignore child units. Child units get added to the entity list
2476 -- of a parent unit, but are not original entities of the parent, and
2477 -- so do not affect whether the parent needs a body.
2479 if Is_Child_Unit (Id) then
2482 -- Ignore formal packages and their renamings
2484 elsif Ekind (Id) = E_Package
2485 and then Nkind (Original_Node (Unit_Declaration_Node (Id))) =
2486 N_Formal_Package_Declaration
2490 -- Otherwise test to see if entity requires a completion. Note that
2491 -- subprogram entities whose declaration does not come from source are
2492 -- ignored here on the basis that we assume the expander will provide an
2493 -- implicit completion at some point.
2495 elsif (Is_Overloadable (Id)
2496 and then not Ekind_In (Id, E_Enumeration_Literal, E_Operator)
2497 and then not Is_Abstract_Subprogram (Id)
2498 and then not Has_Completion (Id)
2499 and then Comes_From_Source (Parent (Id)))
2502 (Ekind (Id) = E_Package
2503 and then Id /= Pack_Id
2504 and then not Has_Completion (Id)
2505 and then Unit_Requires_Body (Id, Do_Abstract_States))
2508 (Ekind (Id) = E_Incomplete_Type
2509 and then No (Full_View (Id))
2510 and then not Is_Generic_Type (Id))
2513 (Ekind_In (Id, E_Task_Type, E_Protected_Type)
2514 and then not Has_Completion (Id))
2517 (Ekind (Id) = E_Generic_Package
2518 and then Id /= Pack_Id
2519 and then not Has_Completion (Id)
2520 and then Unit_Requires_Body (Id, Do_Abstract_States))
2523 (Is_Generic_Subprogram (Id)
2524 and then not Has_Completion (Id))
2528 -- Otherwise the entity does not require completion in a package body
2533 end Requires_Completion_In_Body;
2535 ----------------------------
2536 -- Uninstall_Declarations --
2537 ----------------------------
2539 procedure Uninstall_Declarations (P : Entity_Id) is
2540 Decl : constant Node_Id := Unit_Declaration_Node (P);
2543 Priv_Elmt : Elmt_Id;
2544 Priv_Sub : Entity_Id;
2546 procedure Preserve_Full_Attributes (Priv, Full : Entity_Id);
2547 -- Copy to the private declaration the attributes of the full view that
2548 -- need to be available for the partial view also.
2550 function Type_In_Use (T : Entity_Id) return Boolean;
2551 -- Check whether type or base type appear in an active use_type clause
2553 ------------------------------
2554 -- Preserve_Full_Attributes --
2555 ------------------------------
2557 procedure Preserve_Full_Attributes (Priv, Full : Entity_Id) is
2558 Priv_Is_Base_Type : constant Boolean := Is_Base_Type (Priv);
2561 Set_Size_Info (Priv, (Full));
2562 Set_RM_Size (Priv, RM_Size (Full));
2563 Set_Size_Known_At_Compile_Time
2564 (Priv, Size_Known_At_Compile_Time (Full));
2565 Set_Is_Volatile (Priv, Is_Volatile (Full));
2566 Set_Treat_As_Volatile (Priv, Treat_As_Volatile (Full));
2567 Set_Is_Ada_2005_Only (Priv, Is_Ada_2005_Only (Full));
2568 Set_Is_Ada_2012_Only (Priv, Is_Ada_2012_Only (Full));
2569 Set_Has_Pragma_Unmodified (Priv, Has_Pragma_Unmodified (Full));
2570 Set_Has_Pragma_Unreferenced (Priv, Has_Pragma_Unreferenced (Full));
2571 Set_Has_Pragma_Unreferenced_Objects
2572 (Priv, Has_Pragma_Unreferenced_Objects
2574 if Is_Unchecked_Union (Full) then
2575 Set_Is_Unchecked_Union (Base_Type (Priv));
2577 -- Why is atomic not copied here ???
2579 if Referenced (Full) then
2580 Set_Referenced (Priv);
2583 if Priv_Is_Base_Type then
2584 Set_Is_Controlled (Priv, Is_Controlled (Base_Type (Full)));
2585 Set_Finalize_Storage_Only
2586 (Priv, Finalize_Storage_Only
2587 (Base_Type (Full)));
2588 Propagate_Concurrent_Flags
2589 (Priv, Base_Type (Full));
2590 Set_Has_Controlled_Component
2591 (Priv, Has_Controlled_Component
2592 (Base_Type (Full)));
2595 Set_Freeze_Node (Priv, Freeze_Node (Full));
2597 -- Propagate information of type invariants, which may be specified
2598 -- for the full view.
2600 if Has_Invariants (Full) and not Has_Invariants (Priv) then
2601 Set_Has_Invariants (Priv);
2602 Set_Subprograms_For_Type (Priv, Subprograms_For_Type (Full));
2605 if Is_Tagged_Type (Priv)
2606 and then Is_Tagged_Type (Full)
2607 and then not Error_Posted (Full)
2609 if Is_Tagged_Type (Priv) then
2611 -- If the type is tagged, the tag itself must be available on
2612 -- the partial view, for expansion purposes.
2614 Set_First_Entity (Priv, First_Entity (Full));
2616 -- If there are discriminants in the partial view, these remain
2617 -- visible. Otherwise only the tag itself is visible, and there
2618 -- are no nameable components in the partial view.
2620 if No (Last_Entity (Priv)) then
2621 Set_Last_Entity (Priv, First_Entity (Priv));
2625 Set_Has_Discriminants (Priv, Has_Discriminants (Full));
2627 if Has_Discriminants (Full) then
2628 Set_Discriminant_Constraint (Priv,
2629 Discriminant_Constraint (Full));
2632 end Preserve_Full_Attributes;
2638 function Type_In_Use (T : Entity_Id) return Boolean is
2640 return Scope (Base_Type (T)) = P
2641 and then (In_Use (T) or else In_Use (Base_Type (T)));
2644 -- Start of processing for Uninstall_Declarations
2647 Id := First_Entity (P);
2648 while Present (Id) and then Id /= First_Private_Entity (P) loop
2649 if Debug_Flag_E then
2650 Write_Str ("unlinking visible entity ");
2651 Write_Int (Int (Id));
2655 -- On exit from the package scope, we must preserve the visibility
2656 -- established by use clauses in the current scope. Two cases:
2658 -- a) If the entity is an operator, it may be a primitive operator of
2659 -- a type for which there is a visible use-type clause.
2661 -- b) for other entities, their use-visibility is determined by a
2662 -- visible use clause for the package itself. For a generic instance,
2663 -- the instantiation of the formals appears in the visible part,
2664 -- but the formals are private and remain so.
2666 if Ekind (Id) = E_Function
2667 and then Is_Operator_Symbol_Name (Chars (Id))
2668 and then not Is_Hidden (Id)
2669 and then not Error_Posted (Id)
2671 Set_Is_Potentially_Use_Visible (Id,
2673 or else Type_In_Use (Etype (Id))
2674 or else Type_In_Use (Etype (First_Formal (Id)))
2675 or else (Present (Next_Formal (First_Formal (Id)))
2678 (Etype (Next_Formal (First_Formal (Id))))));
2680 if In_Use (P) and then not Is_Hidden (Id) then
2682 -- A child unit of a use-visible package remains use-visible
2683 -- only if it is itself a visible child unit. Otherwise it
2684 -- would remain visible in other contexts where P is use-
2685 -- visible, because once compiled it stays in the entity list
2686 -- of its parent unit.
2688 if Is_Child_Unit (Id) then
2689 Set_Is_Potentially_Use_Visible
2690 (Id, Is_Visible_Lib_Unit (Id));
2692 Set_Is_Potentially_Use_Visible (Id);
2696 Set_Is_Potentially_Use_Visible (Id, False);
2700 -- Local entities are not immediately visible outside of the package
2702 Set_Is_Immediately_Visible (Id, False);
2704 -- If this is a private type with a full view (for example a local
2705 -- subtype of a private type declared elsewhere), ensure that the
2706 -- full view is also removed from visibility: it may be exposed when
2707 -- swapping views in an instantiation. Similarly, ensure that the
2708 -- use-visibility is properly set on both views.
2710 if Is_Type (Id) and then Present (Full_View (Id)) then
2711 Set_Is_Immediately_Visible (Full_View (Id), False);
2712 Set_Is_Potentially_Use_Visible (Full_View (Id),
2713 Is_Potentially_Use_Visible (Id));
2716 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
2717 Check_Abstract_Overriding (Id);
2718 Check_Conventions (Id);
2721 if Ekind_In (Id, E_Private_Type, E_Limited_Private_Type)
2722 and then No (Full_View (Id))
2723 and then not Is_Generic_Type (Id)
2724 and then not Is_Derived_Type (Id)
2726 Error_Msg_N ("missing full declaration for private type&", Id);
2728 elsif Ekind (Id) = E_Record_Type_With_Private
2729 and then not Is_Generic_Type (Id)
2730 and then No (Full_View (Id))
2732 if Nkind (Parent (Id)) = N_Private_Type_Declaration then
2733 Error_Msg_N ("missing full declaration for private type&", Id);
2736 ("missing full declaration for private extension", Id);
2739 -- Case of constant, check for deferred constant declaration with
2740 -- no full view. Likely just a matter of a missing expression, or
2741 -- accidental use of the keyword constant.
2743 elsif Ekind (Id) = E_Constant
2745 -- OK if constant value present
2747 and then No (Constant_Value (Id))
2749 -- OK if full view present
2751 and then No (Full_View (Id))
2753 -- OK if imported, since that provides the completion
2755 and then not Is_Imported (Id)
2757 -- OK if object declaration replaced by renaming declaration as
2758 -- a result of OK_To_Rename processing (e.g. for concatenation)
2760 and then Nkind (Parent (Id)) /= N_Object_Renaming_Declaration
2762 -- OK if object declaration with the No_Initialization flag set
2764 and then not (Nkind (Parent (Id)) = N_Object_Declaration
2765 and then No_Initialization (Parent (Id)))
2767 -- If no private declaration is present, we assume the user did
2768 -- not intend a deferred constant declaration and the problem
2769 -- is simply that the initializing expression is missing.
2771 if not Has_Private_Declaration (Etype (Id)) then
2773 -- We assume that the user did not intend a deferred constant
2774 -- declaration, and the expression is just missing.
2777 ("constant declaration requires initialization expression",
2780 if Is_Limited_Type (Etype (Id)) then
2782 ("\if variable intended, remove CONSTANT from declaration",
2786 -- Otherwise if a private declaration is present, then we are
2787 -- missing the full declaration for the deferred constant.
2791 ("missing full declaration for deferred constant (RM 7.4)",
2794 if Is_Limited_Type (Etype (Id)) then
2796 ("\if variable intended, remove CONSTANT from declaration",
2805 -- If the specification was installed as the parent of a public child
2806 -- unit, the private declarations were not installed, and there is
2809 if not In_Private_Part (P) then
2812 Set_In_Private_Part (P, False);
2815 -- Make private entities invisible and exchange full and private
2816 -- declarations for private types. Id is now the first private entity
2819 while Present (Id) loop
2820 if Debug_Flag_E then
2821 Write_Str ("unlinking private entity ");
2822 Write_Int (Int (Id));
2826 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
2827 Check_Abstract_Overriding (Id);
2828 Check_Conventions (Id);
2831 Set_Is_Immediately_Visible (Id, False);
2833 if Is_Private_Base_Type (Id) and then Present (Full_View (Id)) then
2834 Full := Full_View (Id);
2836 -- If the partial view is not declared in the visible part of the
2837 -- package (as is the case when it is a type derived from some
2838 -- other private type in the private part of the current package),
2839 -- no exchange takes place.
2842 or else List_Containing (Parent (Id)) /=
2843 Visible_Declarations (Specification (Decl))
2848 -- The entry in the private part points to the full declaration,
2849 -- which is currently visible. Exchange them so only the private
2850 -- type declaration remains accessible, and link private and full
2851 -- declaration in the opposite direction. Before the actual
2852 -- exchange, we copy back attributes of the full view that must
2853 -- be available to the partial view too.
2855 Preserve_Full_Attributes (Id, Full);
2857 Set_Is_Potentially_Use_Visible (Id, In_Use (P));
2859 -- The following test may be redundant, as this is already
2860 -- diagnosed in sem_ch3. ???
2862 if not Is_Definite_Subtype (Full)
2863 and then Is_Definite_Subtype (Id)
2865 Error_Msg_Sloc := Sloc (Parent (Id));
2867 ("full view of& not compatible with declaration#", Full, Id);
2870 -- Swap out the subtypes and derived types of Id that
2871 -- were compiled in this scope, or installed previously
2872 -- by Install_Private_Declarations.
2874 -- Before we do the swap, we verify the presence of the Full_View
2875 -- field which may be empty due to a swap by a previous call to
2876 -- End_Package_Scope (e.g. from the freezing mechanism).
2878 Priv_Elmt := First_Elmt (Private_Dependents (Id));
2879 while Present (Priv_Elmt) loop
2880 Priv_Sub := Node (Priv_Elmt);
2882 if Present (Full_View (Priv_Sub)) then
2883 if Scope (Priv_Sub) = P
2884 or else not In_Open_Scopes (Scope (Priv_Sub))
2886 Set_Is_Immediately_Visible (Priv_Sub, False);
2889 if Is_Visible_Dependent (Priv_Sub) then
2890 Preserve_Full_Attributes
2891 (Priv_Sub, Full_View (Priv_Sub));
2892 Replace_Elmt (Priv_Elmt, Full_View (Priv_Sub));
2893 Exchange_Declarations (Priv_Sub);
2897 Next_Elmt (Priv_Elmt);
2900 -- Now restore the type itself to its private view
2902 Exchange_Declarations (Id);
2904 -- If we have installed an underlying full view for a type derived
2905 -- from a private type in a child unit, restore the proper views
2906 -- of private and full view. See corresponding code in
2907 -- Install_Private_Declarations.
2909 -- After the exchange, Full denotes the private type in the
2910 -- visible part of the package.
2912 if Is_Private_Base_Type (Full)
2913 and then Present (Full_View (Full))
2914 and then Present (Underlying_Full_View (Full))
2915 and then In_Package_Body (Current_Scope)
2917 Set_Full_View (Full, Underlying_Full_View (Full));
2918 Set_Underlying_Full_View (Full, Empty);
2921 elsif Ekind (Id) = E_Incomplete_Type
2922 and then Comes_From_Source (Id)
2923 and then No (Full_View (Id))
2925 -- Mark Taft amendment types. Verify that there are no primitive
2926 -- operations declared for the type (3.10.1(9)).
2928 Set_Has_Completion_In_Body (Id);
2935 Elmt := First_Elmt (Private_Dependents (Id));
2936 while Present (Elmt) loop
2937 Subp := Node (Elmt);
2939 -- Is_Primitive is tested because there can be cases where
2940 -- nonprimitive subprograms (in nested packages) are added
2941 -- to the Private_Dependents list.
2943 if Is_Overloadable (Subp) and then Is_Primitive (Subp) then
2945 ("type& must be completed in the private part",
2948 -- The result type of an access-to-function type cannot be a
2949 -- Taft-amendment type, unless the version is Ada 2012 or
2950 -- later (see AI05-151).
2952 elsif Ada_Version < Ada_2012
2953 and then Ekind (Subp) = E_Subprogram_Type
2955 if Etype (Subp) = Id
2957 (Is_Class_Wide_Type (Etype (Subp))
2958 and then Etype (Etype (Subp)) = Id)
2961 ("type& must be completed in the private part",
2962 Associated_Node_For_Itype (Subp), Id);
2970 elsif not Is_Child_Unit (Id)
2971 and then (not Is_Private_Type (Id) or else No (Full_View (Id)))
2974 Set_Is_Potentially_Use_Visible (Id, False);
2980 end Uninstall_Declarations;
2982 ------------------------
2983 -- Unit_Requires_Body --
2984 ------------------------
2986 function Unit_Requires_Body
2987 (Pack_Id : Entity_Id;
2988 Do_Abstract_States : Boolean := False) return Boolean
2992 Requires_Body : Boolean := False;
2993 -- Flag set when the unit has at least one construct that requries
2994 -- completion in a body.
2997 -- Imported entity never requires body. Right now, only subprograms can
2998 -- be imported, but perhaps in the future we will allow import of
3001 if Is_Imported (Pack_Id) then
3004 -- Body required if library package with pragma Elaborate_Body
3006 elsif Has_Pragma_Elaborate_Body (Pack_Id) then
3009 -- Body required if subprogram
3011 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
3014 -- Treat a block as requiring a body
3016 elsif Ekind (Pack_Id) = E_Block then
3019 elsif Ekind (Pack_Id) = E_Package
3020 and then Nkind (Parent (Pack_Id)) = N_Package_Specification
3021 and then Present (Generic_Parent (Parent (Pack_Id)))
3024 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
3026 if Has_Pragma_Elaborate_Body (G_P) then
3032 -- Traverse the entity chain of the package and look for constructs that
3033 -- require a completion in a body.
3035 E := First_Entity (Pack_Id);
3036 while Present (E) loop
3038 -- Skip abstract states because their completion depends on several
3039 -- criteria (see below).
3041 if Ekind (E) = E_Abstract_State then
3044 elsif Requires_Completion_In_Body
3045 (E, Pack_Id, Do_Abstract_States)
3047 Requires_Body := True;
3054 -- A [generic] package that defines at least one non-null abstract state
3055 -- requires a completion only when at least one other construct requires
3056 -- a completion in a body (SPARK RM 7.1.4(4) and (6)). This check is not
3057 -- performed if the caller requests this behavior.
3059 if Do_Abstract_States
3060 and then Ekind_In (Pack_Id, E_Generic_Package, E_Package)
3061 and then Has_Non_Null_Abstract_State (Pack_Id)
3062 and then Requires_Body
3067 return Requires_Body;
3068 end Unit_Requires_Body;
3070 -----------------------------
3071 -- Unit_Requires_Body_Info --
3072 -----------------------------
3074 procedure Unit_Requires_Body_Info (Pack_Id : Entity_Id) is
3078 -- An imported entity never requires body. Right now, only subprograms
3079 -- can be imported, but perhaps in the future we will allow import of
3082 if Is_Imported (Pack_Id) then
3085 -- Body required if library package with pragma Elaborate_Body
3087 elsif Has_Pragma_Elaborate_Body (Pack_Id) then
3088 Error_Msg_N ("info: & requires body (Elaborate_Body)?Y?", Pack_Id);
3090 -- Body required if subprogram
3092 elsif Is_Subprogram_Or_Generic_Subprogram (Pack_Id) then
3093 Error_Msg_N ("info: & requires body (subprogram case)?Y?", Pack_Id);
3095 -- Body required if generic parent has Elaborate_Body
3097 elsif Ekind (Pack_Id) = E_Package
3098 and then Nkind (Parent (Pack_Id)) = N_Package_Specification
3099 and then Present (Generic_Parent (Parent (Pack_Id)))
3102 G_P : constant Entity_Id := Generic_Parent (Parent (Pack_Id));
3104 if Has_Pragma_Elaborate_Body (G_P) then
3106 ("info: & requires body (generic parent Elaborate_Body)?Y?",
3111 -- A [generic] package that introduces at least one non-null abstract
3112 -- state requires completion. However, there is a separate rule that
3113 -- requires that such a package have a reason other than this for a
3114 -- body being required (if necessary a pragma Elaborate_Body must be
3115 -- provided). If Ignore_Abstract_State is True, we don't do this check
3116 -- (so we can use Unit_Requires_Body to check for some other reason).
3118 elsif Ekind_In (Pack_Id, E_Generic_Package, E_Package)
3119 and then Present (Abstract_States (Pack_Id))
3120 and then not Is_Null_State
3121 (Node (First_Elmt (Abstract_States (Pack_Id))))
3124 ("info: & requires body (non-null abstract state aspect)?Y?",
3128 -- Otherwise search entity chain for entity requiring completion
3130 E := First_Entity (Pack_Id);
3131 while Present (E) loop
3132 if Requires_Completion_In_Body (E, Pack_Id) then
3133 Error_Msg_Node_2 := E;
3135 ("info: & requires body (& requires completion)?Y?", E, Pack_Id);
3140 end Unit_Requires_Body_Info;