1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2004, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 -- This package contains the routines to process package specifications and
28 -- bodies. The most important semantic aspects of package processing are the
29 -- handling of private and full declarations, and the construction of
30 -- dispatch tables for tagged types.
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_Dbug; use Exp_Dbug;
40 with Lib.Xref; use Lib.Xref;
41 with Namet; use Namet;
42 with Nmake; use Nmake;
43 with Nlists; use Nlists;
45 with Output; use Output;
47 with Sem_Cat; use Sem_Cat;
48 with Sem_Ch3; use Sem_Ch3;
49 with Sem_Ch6; use Sem_Ch6;
50 with Sem_Ch8; use Sem_Ch8;
51 with Sem_Ch10; use Sem_Ch10;
52 with Sem_Ch12; use Sem_Ch12;
53 with Sem_Util; use Sem_Util;
54 with Sem_Warn; use Sem_Warn;
55 with Snames; use Snames;
56 with Stand; use Stand;
57 with Sinfo; use Sinfo;
58 with Sinput; use Sinput;
61 package body Sem_Ch7 is
63 -----------------------------------
64 -- Handling private declarations --
65 -----------------------------------
67 -- The principle that each entity has a single defining occurrence clashes
68 -- with the presence of two separate definitions for private types: the
69 -- first is the private type declaration, and the second is the full type
70 -- declaration. It is important that all references to the type point to
71 -- the same defining occurrence, namely the first one. To enforce the two
72 -- separate views of the entity, the corresponding information is swapped
73 -- between the two declarations. Outside of the package, the defining
74 -- occurrence only contains the private declaration information, while in
75 -- the private part and the body of the package the defining occurrence
76 -- contains the full declaration. To simplify the swap, the defining
77 -- occurrence that currently holds the private declaration points to the
78 -- full declaration. During semantic processing the defining occurrence
79 -- also points to a list of private dependents, that is to say access types
80 -- or composite types whose designated types or component types are
81 -- subtypes or derived types of the private type in question. After the
82 -- full declaration has been seen, the private dependents are updated to
83 -- indicate that they have full definitions.
85 -----------------------
86 -- Local Subprograms --
87 -----------------------
89 procedure Install_Package_Entity (Id : Entity_Id);
90 -- Basic procedure for the previous two. Places one entity on its
91 -- visibility chain, and recurses on the visible part if the entity
92 -- is an inner package.
94 function Is_Private_Base_Type (E : Entity_Id) return Boolean;
95 -- True for a private type that is not a subtype.
97 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean;
98 -- If the private dependent is a private type whose full view is
99 -- derived from the parent type, its full properties are revealed
100 -- only if we are in the immediate scope of the private dependent.
101 -- Should this predicate be tightened further???
103 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id);
104 -- Called upon entering the private part of a public child package
105 -- and the body of a nested package, to potentially declare certain
106 -- inherited subprograms that were inherited by types in the visible
107 -- part, but whose declaration was deferred because the parent
108 -- operation was private and not visible at that point. These
109 -- subprograms are located by traversing the visible part declarations
110 -- looking for non-private type extensions and then examining each of
111 -- the primitive operations of such types to find those that were
112 -- inherited but declared with a special internal name. Each such
113 -- operation is now declared as an operation with a normal name (using
114 -- the name of the parent operation) and replaces the previous implicit
115 -- operation in the primitive operations list of the type. If the
116 -- inherited private operation has been overridden, then it's
117 -- replaced by the overriding operation.
119 --------------------------
120 -- Analyze_Package_Body --
121 --------------------------
123 procedure Analyze_Package_Body (N : Node_Id) is
124 Loc : constant Source_Ptr := Sloc (N);
128 Last_Spec_Entity : Entity_Id;
132 procedure Install_Composite_Operations (P : Entity_Id);
133 -- Composite types declared in the current scope may depend on
134 -- types that were private at the point of declaration, and whose
135 -- full view is now in scope. Indicate that the corresponding
136 -- operations on the composite type are available.
138 ----------------------------------
139 -- Install_Composite_Operations --
140 ----------------------------------
142 procedure Install_Composite_Operations (P : Entity_Id) is
146 Id := First_Entity (P);
148 while Present (Id) loop
151 and then (Is_Limited_Composite (Id)
152 or else Is_Private_Composite (Id))
153 and then No (Private_Component (Id))
155 Set_Is_Limited_Composite (Id, False);
156 Set_Is_Private_Composite (Id, False);
161 end Install_Composite_Operations;
163 -- Start of processing for Analyze_Package_Body
166 -- Find corresponding package specification, and establish the
167 -- current scope. The visible defining entity for the package is the
168 -- defining occurrence in the spec. On exit from the package body, all
169 -- body declarations are attached to the defining entity for the body,
170 -- but the later is never used for name resolution. In this fashion
171 -- there is only one visible entity that denotes the package.
174 Write_Str ("==== Compiling package body ");
175 Write_Name (Chars (Defining_Entity (N)));
176 Write_Str (" from ");
177 Write_Location (Loc);
181 -- Set Body_Id. Note that this Will be reset to point to the
182 -- generic copy later on in the generic case.
184 Body_Id := Defining_Entity (N);
186 if Present (Corresponding_Spec (N)) then
188 -- Body is body of package instantiation. Corresponding spec
189 -- has already been set.
191 Spec_Id := Corresponding_Spec (N);
192 Pack_Decl := Unit_Declaration_Node (Spec_Id);
195 Spec_Id := Current_Entity_In_Scope (Defining_Entity (N));
198 and then Is_Package (Spec_Id)
200 Pack_Decl := Unit_Declaration_Node (Spec_Id);
202 if Nkind (Pack_Decl) = N_Package_Renaming_Declaration then
203 Error_Msg_N ("cannot supply body for package renaming", N);
206 elsif Present (Corresponding_Body (Pack_Decl)) then
207 Error_Msg_N ("redefinition of package body", N);
212 Error_Msg_N ("missing specification for package body", N);
216 if Is_Package (Spec_Id)
218 (Scope (Spec_Id) = Standard_Standard
219 or else Is_Child_Unit (Spec_Id))
220 and then not Unit_Requires_Body (Spec_Id)
222 if Ada_Version = Ada_83 then
224 ("optional package body (not allowed in Ada 95)?", N);
227 ("spec of this package does not allow a body", N);
232 Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));
233 Style.Check_Identifier (Body_Id, Spec_Id);
235 if Is_Child_Unit (Spec_Id) then
236 if Nkind (Parent (N)) /= N_Compilation_Unit then
238 ("body of child unit& cannot be an inner package", N, Spec_Id);
241 Set_Is_Child_Unit (Body_Id);
244 -- Generic package case
246 if Ekind (Spec_Id) = E_Generic_Package then
248 -- Disable expansion and perform semantic analysis on copy.
249 -- The unannotated body will be used in all instantiations.
251 Body_Id := Defining_Entity (N);
252 Set_Ekind (Body_Id, E_Package_Body);
253 Set_Scope (Body_Id, Scope (Spec_Id));
254 Set_Body_Entity (Spec_Id, Body_Id);
255 Set_Spec_Entity (Body_Id, Spec_Id);
257 New_N := Copy_Generic_Node (N, Empty, Instantiating => False);
260 -- Update Body_Id to point to the copied node for the remainder
261 -- of the processing.
263 Body_Id := Defining_Entity (N);
267 -- The Body_Id is that of the copied node in the generic case, the
268 -- current node otherwise. Note that N was rewritten above, so we
269 -- must be sure to get the latest Body_Id value.
271 Set_Ekind (Body_Id, E_Package_Body);
272 Set_Body_Entity (Spec_Id, Body_Id);
273 Set_Spec_Entity (Body_Id, Spec_Id);
275 -- Defining name for the package body is not a visible entity: Only
276 -- the defining name for the declaration is visible.
278 Set_Etype (Body_Id, Standard_Void_Type);
279 Set_Scope (Body_Id, Scope (Spec_Id));
280 Set_Corresponding_Spec (N, Spec_Id);
281 Set_Corresponding_Body (Pack_Decl, Body_Id);
283 -- The body entity is not used for semantics or code generation, but
284 -- it is attached to the entity list of the enclosing scope to simplify
285 -- the listing of back-annotations for the types it main contain.
287 if Scope (Spec_Id) /= Standard_Standard then
288 Append_Entity (Body_Id, Scope (Spec_Id));
291 -- Indicate that we are currently compiling the body of the package.
293 Set_In_Package_Body (Spec_Id);
294 Set_Has_Completion (Spec_Id);
295 Last_Spec_Entity := Last_Entity (Spec_Id);
299 Set_Categorization_From_Pragmas (N);
301 Install_Visible_Declarations (Spec_Id);
302 Install_Private_Declarations (Spec_Id);
303 Install_Private_With_Clauses (Spec_Id);
304 Install_Composite_Operations (Spec_Id);
306 if Ekind (Spec_Id) = E_Generic_Package then
307 Set_Use (Generic_Formal_Declarations (Pack_Decl));
310 Set_Use (Visible_Declarations (Specification (Pack_Decl)));
311 Set_Use (Private_Declarations (Specification (Pack_Decl)));
313 -- This is a nested package, so it may be necessary to declare
314 -- certain inherited subprograms that are not yet visible because
315 -- the parent type's subprograms are now visible.
317 if Ekind (Scope (Spec_Id)) = E_Package
318 and then Scope (Spec_Id) /= Standard_Standard
320 Declare_Inherited_Private_Subprograms (Spec_Id);
323 if Present (Declarations (N)) then
324 Analyze_Declarations (Declarations (N));
327 HSS := Handled_Statement_Sequence (N);
329 if Present (HSS) then
330 Process_End_Label (HSS, 't', Spec_Id);
333 -- Check that elaboration code in a preelaborable package body is
334 -- empty other than null statements and labels (RM 10.2.1(6)).
336 Validate_Null_Statement_Sequence (N);
339 Validate_Categorization_Dependency (N, Spec_Id);
340 Check_Completion (Body_Id);
342 -- Generate start of body reference. Note that we do this fairly late,
343 -- because the call will use In_Extended_Main_Source_Unit as a check,
344 -- and we want to make sure that Corresponding_Stub links are set
346 Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);
348 -- For a generic package, collect global references and mark
349 -- them on the original body so that they are not resolved
350 -- again at the point of instantiation.
352 if Ekind (Spec_Id) /= E_Package then
353 Save_Global_References (Original_Node (N));
357 -- The entities of the package body have so far been chained onto
358 -- the declaration chain for the spec. That's been fine while we
359 -- were in the body, since we wanted them to be visible, but now
360 -- that we are leaving the package body, they are no longer visible,
361 -- so we remove them from the entity chain of the package spec entity,
362 -- and copy them to the entity chain of the package body entity, where
363 -- they will never again be visible.
365 if Present (Last_Spec_Entity) then
366 Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity));
367 Set_Next_Entity (Last_Spec_Entity, Empty);
368 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
369 Set_Last_Entity (Spec_Id, Last_Spec_Entity);
372 Set_First_Entity (Body_Id, First_Entity (Spec_Id));
373 Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));
374 Set_First_Entity (Spec_Id, Empty);
375 Set_Last_Entity (Spec_Id, Empty);
378 End_Package_Scope (Spec_Id);
380 -- All entities declared in body are not visible.
386 E := First_Entity (Body_Id);
388 while Present (E) loop
389 Set_Is_Immediately_Visible (E, False);
390 Set_Is_Potentially_Use_Visible (E, False);
393 -- Child units may appear on the entity list (for example if
394 -- they appear in the context of a subunit) but they are not
397 if not Is_Child_Unit (E) then
398 Set_Is_Package_Body_Entity (E);
405 Check_References (Body_Id);
407 -- For a generic unit, check that the formal parameters are referenced,
408 -- and that local variables are used, as for regular packages.
410 if Ekind (Spec_Id) = E_Generic_Package then
411 Check_References (Spec_Id);
414 -- The processing so far has made all entities of the package body
415 -- public (i.e. externally visible to the linker). This is in general
416 -- necessary, since inlined or generic bodies, for which code is
417 -- generated in other units, may need to see these entities. The
418 -- following loop runs backwards from the end of the entities of the
419 -- package body making these entities invisible until we reach a
420 -- referencer, i.e. a declaration that could reference a previous
421 -- declaration, a generic body or an inlined body, or a stub (which
422 -- may contain either of these). This is of course an approximation,
423 -- but it is conservative and definitely correct.
425 -- We only do this at the outer (library) level non-generic packages.
426 -- The reason is simply to cut down on the number of external symbols
427 -- generated, so this is simply an optimization of the efficiency
428 -- of the compilation process. It has no other effect.
430 if (Scope (Spec_Id) = Standard_Standard or else Is_Child_Unit (Spec_Id))
431 and then not Is_Generic_Unit (Spec_Id)
432 and then Present (Declarations (N))
434 Make_Non_Public_Where_Possible : declare
436 function Has_Referencer
440 -- Traverse the given list of declarations in reverse order.
441 -- Return True as soon as a referencer is reached. Return
442 -- False if none is found. The Outer parameter is True for
443 -- the outer level call, and False for inner level calls for
444 -- nested packages. If Outer is True, then any entities up
445 -- to the point of hitting a referencer get their Is_Public
446 -- flag cleared, so that the entities will be treated as
447 -- static entities in the C sense, and need not have fully
448 -- qualified names. For inner levels, we need all names to
449 -- be fully qualified to deal with the same name appearing
450 -- in parallel packages (right now this is tied to their
457 function Has_Referencer
474 while Present (D) loop
477 if K in N_Body_Stub then
480 elsif K = N_Subprogram_Body then
481 if Acts_As_Spec (D) then
482 E := Defining_Entity (D);
484 -- An inlined body acts as a referencer. Note also
485 -- that we never reset Is_Public for an inlined
486 -- subprogram. Gigi requires Is_Public to be set.
488 -- Note that we test Has_Pragma_Inline here rather
489 -- than Is_Inlined. We are compiling this for a
490 -- client, and it is the client who will decide
491 -- if actual inlining should occur, so we need to
492 -- assume that the procedure could be inlined for
493 -- the purpose of accessing global entities.
495 if Has_Pragma_Inline (E) then
498 Set_Is_Public (E, False);
502 E := Corresponding_Spec (D);
505 and then (Is_Generic_Unit (E)
506 or else Has_Pragma_Inline (E)
507 or else Is_Inlined (E))
513 -- Processing for package bodies
515 elsif K = N_Package_Body
516 and then Present (Corresponding_Spec (D))
518 E := Corresponding_Spec (D);
520 -- Generic package body is a referencer. It would
521 -- seem that we only have to consider generics that
522 -- can be exported, i.e. where the corresponding spec
523 -- is the spec of the current package, but because of
524 -- nested instantiations, a fully private generic
525 -- body may export other private body entities.
527 if Is_Generic_Unit (E) then
530 -- For non-generic package body, recurse into body
531 -- unless this is an instance, we ignore instances
532 -- since they cannot have references that affect
535 elsif not Is_Generic_Instance (E) then
537 (Declarations (D), Outer => False)
543 -- Processing for package specs, recurse into declarations.
544 -- Again we skip this for the case of generic instances.
546 elsif K = N_Package_Declaration then
547 S := Specification (D);
549 if not Is_Generic_Unit (Defining_Entity (S)) then
551 (Private_Declarations (S), Outer => False)
555 (Visible_Declarations (S), Outer => False)
561 -- Objects and exceptions need not be public if we have
562 -- not encountered a referencer so far. We only reset
563 -- the flag for outer level entities that are not
564 -- imported/exported, and which have no interface name.
566 elsif K = N_Object_Declaration
567 or else K = N_Exception_Declaration
568 or else K = N_Subprogram_Declaration
570 E := Defining_Entity (D);
573 and then not Is_Imported (E)
574 and then not Is_Exported (E)
575 and then No (Interface_Name (E))
577 Set_Is_Public (E, False);
587 -- Start of processing for Make_Non_Public_Where_Possible
592 pragma Warnings (Off, Discard);
595 Discard := Has_Referencer (Declarations (N), Outer => True);
597 end Make_Non_Public_Where_Possible;
600 -- If expander is not active, then here is where we turn off the
601 -- In_Package_Body flag, otherwise it is turned off at the end of
602 -- the corresponding expansion routine. If this is an instance body,
603 -- we need to qualify names of local entities, because the body may
604 -- have been compiled as a preliminary to another instantiation.
606 if not Expander_Active then
607 Set_In_Package_Body (Spec_Id, False);
609 if Is_Generic_Instance (Spec_Id)
610 and then Operating_Mode = Generate_Code
612 Qualify_Entity_Names (N);
615 end Analyze_Package_Body;
617 ---------------------------------
618 -- Analyze_Package_Declaration --
619 ---------------------------------
621 procedure Analyze_Package_Declaration (N : Node_Id) is
622 Id : constant Node_Id := Defining_Entity (N);
626 Generate_Definition (Id);
628 Set_Ekind (Id, E_Package);
629 Set_Etype (Id, Standard_Void_Type);
633 PF := Is_Pure (Enclosing_Lib_Unit_Entity);
634 Set_Is_Pure (Id, PF);
636 Set_Categorization_From_Pragmas (N);
639 Write_Str ("==== Compiling package spec ");
640 Write_Name (Chars (Id));
641 Write_Str (" from ");
642 Write_Location (Sloc (N));
646 Analyze (Specification (N));
647 Validate_Categorization_Dependency (N, Id);
648 End_Package_Scope (Id);
650 -- For a compilation unit, indicate whether it needs a body, and
651 -- whether elaboration warnings may be meaningful on it.
653 if Nkind (Parent (N)) = N_Compilation_Unit then
654 Set_Body_Required (Parent (N), Unit_Requires_Body (Id));
656 if not Body_Required (Parent (N)) then
657 Set_Suppress_Elaboration_Warnings (Id);
660 Validate_RT_RAT_Component (N);
662 end Analyze_Package_Declaration;
664 -----------------------------------
665 -- Analyze_Package_Specification --
666 -----------------------------------
668 -- Note that this code is shared for the analysis of generic package
669 -- specs (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).
671 procedure Analyze_Package_Specification (N : Node_Id) is
672 Id : constant Entity_Id := Defining_Entity (N);
673 Orig_Decl : constant Node_Id := Original_Node (Parent (N));
674 Vis_Decls : constant List_Id := Visible_Declarations (N);
675 Priv_Decls : constant List_Id := Private_Declarations (N);
678 Public_Child : Boolean;
680 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id);
681 -- Clears constant indications (Never_Set_In_Source, Constant_Value,
682 -- and Is_True_Constant) on all variables that are entities of Id,
683 -- and on the chain whose first element is FE. A recursive call is
684 -- made for all packages and generic packages.
686 procedure Generate_Parent_References;
687 -- For a child unit, generate references to parent units, for
688 -- GPS navigation purposes.
690 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean;
691 -- Child and Unit are entities of compilation units. True if Child
692 -- is a public child of Parent as defined in 10.1.1
694 procedure Inspect_Deferred_Constant_Completion;
695 -- Examines the deferred constants in the private part of the
696 -- package specification. Emits the error "constant declaration
697 -- requires initialization expression " if not completed by an
700 ---------------------
701 -- Clear_Constants --
702 ---------------------
704 procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id) is
708 -- Ignore package renamings, not interesting and they can
709 -- cause self referential loops in the code below.
711 if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then
715 -- Note: in the loop below, the check for Next_Entity pointing
716 -- back to the package entity seems very odd, but it is needed,
717 -- because this kind of unexpected circularity does occur ???
720 while Present (E) and then E /= Id loop
721 if Ekind (E) = E_Variable then
722 Set_Never_Set_In_Source (E, False);
723 Set_Is_True_Constant (E, False);
724 Set_Current_Value (E, Empty);
725 Set_Is_Known_Non_Null (E, False);
727 elsif Ekind (E) = E_Package
729 Ekind (E) = E_Generic_Package
731 Clear_Constants (E, First_Entity (E));
732 Clear_Constants (E, First_Private_Entity (E));
739 --------------------------------
740 -- Generate_Parent_References --
741 --------------------------------
743 procedure Generate_Parent_References is
744 Decl : constant Node_Id := Parent (N);
747 if Id = Cunit_Entity (Main_Unit)
748 or else Parent (Decl) = Library_Unit (Cunit (Main_Unit))
750 Generate_Reference (Id, Scope (Id), 'k', False);
752 elsif Nkind (Unit (Cunit (Main_Unit))) /= N_Subprogram_Body
753 and then Nkind (Unit (Cunit (Main_Unit))) /= N_Subunit
755 -- If current unit is an ancestor of main unit, generate
756 -- a reference to its own parent.
760 Main_Spec : Node_Id := Unit (Cunit (Main_Unit));
763 if Nkind (Main_Spec) = N_Package_Body then
764 Main_Spec := Unit (Library_Unit (Cunit (Main_Unit)));
767 U := Parent_Spec (Main_Spec);
768 while Present (U) loop
769 if U = Parent (Decl) then
770 Generate_Reference (Id, Scope (Id), 'k', False);
773 elsif Nkind (Unit (U)) = N_Package_Body then
777 U := Parent_Spec (Unit (U));
782 end Generate_Parent_References;
784 ---------------------
785 -- Is_Public_Child --
786 ---------------------
788 function Is_Public_Child (Child, Unit : Entity_Id) return Boolean is
790 if not Is_Private_Descendant (Child) then
794 return not Private_Present (
795 Parent (Unit_Declaration_Node (Child)));
797 return Is_Public_Child (Scope (Child), Unit);
802 --------------------------------------------
803 -- Inspect_Deferred_Constant_Completion --
804 --------------------------------------------
806 procedure Inspect_Deferred_Constant_Completion is
810 Decl := First (Priv_Decls);
811 while Present (Decl) loop
813 -- Deferred constant signature
815 if Nkind (Decl) = N_Object_Declaration
816 and then Constant_Present (Decl)
817 and then No (Expression (Decl))
819 -- No need to check internally generated constants
821 and then Comes_From_Source (Decl)
823 -- The constant is not completed. A full object declaration
824 -- or a pragma Import complete a deferred constant.
826 and then not Has_Completion (Defining_Identifier (Decl))
829 ("constant declaration requires initialization expression",
830 Defining_Identifier (Decl));
836 end Inspect_Deferred_Constant_Completion;
838 -- Start of processing for Analyze_Package_Specification
841 if Present (Vis_Decls) then
842 Analyze_Declarations (Vis_Decls);
845 -- Verify that incomplete types have received full declarations.
847 E := First_Entity (Id);
848 while Present (E) loop
849 if Ekind (E) = E_Incomplete_Type
850 and then No (Full_View (E))
852 Error_Msg_N ("no declaration in visible part for incomplete}", E);
858 if Is_Remote_Call_Interface (Id)
859 and then Nkind (Parent (Parent (N))) = N_Compilation_Unit
861 Validate_RCI_Declarations (Id);
864 -- Save global references in the visible declarations, before
865 -- installing private declarations of parent unit if there is one,
866 -- because the privacy status of types defined in the parent will
867 -- change. This is only relevant for generic child units, but is
868 -- done in all cases for uniformity.
870 if Ekind (Id) = E_Generic_Package
871 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
874 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
875 Save_Priv : constant List_Id := Private_Declarations (Orig_Spec);
878 Set_Private_Declarations (Orig_Spec, Empty_List);
879 Save_Global_References (Orig_Decl);
880 Set_Private_Declarations (Orig_Spec, Save_Priv);
884 -- If package is a public child unit, then make the private
885 -- declarations of the parent visible.
887 Public_Child := False;
889 if Present (Parent_Spec (Parent (N))) then
890 Generate_Parent_References;
893 Par : Entity_Id := Id;
897 while Scope (Par) /= Standard_Standard
898 and then Is_Public_Child (Id, Par)
900 Public_Child := True;
902 Install_Private_Declarations (Par);
903 Install_Private_With_Clauses (Par);
904 Pack_Decl := Unit_Declaration_Node (Par);
905 Set_Use (Private_Declarations (Specification (Pack_Decl)));
910 if Is_Compilation_Unit (Id) then
911 Install_Private_With_Clauses (Id);
914 -- Analyze private part if present. The flag In_Private_Part is
915 -- reset in End_Package_Scope.
917 L := Last_Entity (Id);
919 if Present (Priv_Decls) then
920 Set_In_Private_Part (Id);
922 -- Upon entering a public child's private part, it may be
923 -- necessary to declare subprograms that were derived in
924 -- the package visible part but not yet made visible.
927 Declare_Inherited_Private_Subprograms (Id);
930 Analyze_Declarations (Priv_Decls);
932 -- Check the private declarations for incomplete deferred
935 Inspect_Deferred_Constant_Completion;
937 -- The first private entity is the immediate follower of the last
938 -- visible entity, if there was one.
941 Set_First_Private_Entity (Id, Next_Entity (L));
943 Set_First_Private_Entity (Id, First_Entity (Id));
946 -- There may be inherited private subprograms that need to be
947 -- declared, even in the absence of an explicit private part.
948 -- If there are any public declarations in the package and
949 -- the package is a public child unit, then an implicit private
952 elsif Present (L) and then Public_Child then
953 Set_In_Private_Part (Id);
954 Declare_Inherited_Private_Subprograms (Id);
955 Set_First_Private_Entity (Id, Next_Entity (L));
958 -- Check rule of 3.6(11), which in general requires
959 -- waiting till all full types have been seen.
961 E := First_Entity (Id);
962 while Present (E) loop
963 if Ekind (E) = E_Record_Type or else Ekind (E) = E_Array_Type then
964 Check_Aliased_Component_Types (E);
970 if Ekind (Id) = E_Generic_Package
971 and then Nkind (Orig_Decl) = N_Generic_Package_Declaration
972 and then Present (Priv_Decls)
974 -- Save global references in private declarations, ignoring the
975 -- visible declarations that were processed earlier.
978 Orig_Spec : constant Node_Id := Specification (Orig_Decl);
979 Save_Vis : constant List_Id := Visible_Declarations (Orig_Spec);
980 Save_Form : constant List_Id :=
981 Generic_Formal_Declarations (Orig_Decl);
984 Set_Visible_Declarations (Orig_Spec, Empty_List);
985 Set_Generic_Formal_Declarations (Orig_Decl, Empty_List);
986 Save_Global_References (Orig_Decl);
987 Set_Generic_Formal_Declarations (Orig_Decl, Save_Form);
988 Set_Visible_Declarations (Orig_Spec, Save_Vis);
992 Process_End_Label (N, 'e', Id);
994 -- For the case of a library level package, we must go through all
995 -- the entities clearing the indications that the value may be
996 -- constant and not modified. Why? Because any client of this
997 -- package may modify these values freely from anywhere. This
998 -- also applies to any nested packages or generic packages.
1000 -- For now we unconditionally clear constants for packages that
1001 -- are instances of generic packages. The reason is that we do not
1002 -- have the body yet, and we otherwise think things are unreferenced
1003 -- when they are not. This should be fixed sometime (the effect is
1004 -- not terrible, we just lose some warnings, and also some cases
1005 -- of value propagation) ???
1007 if Is_Library_Level_Entity (Id)
1008 or else Is_Generic_Instance (Id)
1010 Clear_Constants (Id, First_Entity (Id));
1011 Clear_Constants (Id, First_Private_Entity (Id));
1013 end Analyze_Package_Specification;
1015 --------------------------------------
1016 -- Analyze_Private_Type_Declaration --
1017 --------------------------------------
1019 procedure Analyze_Private_Type_Declaration (N : Node_Id) is
1020 PF : constant Boolean := Is_Pure (Enclosing_Lib_Unit_Entity);
1021 Id : constant Entity_Id := Defining_Identifier (N);
1024 Generate_Definition (Id);
1025 Set_Is_Pure (Id, PF);
1026 Init_Size_Align (Id);
1028 if (Ekind (Current_Scope) /= E_Package
1029 and then Ekind (Current_Scope) /= E_Generic_Package)
1030 or else In_Private_Part (Current_Scope)
1032 Error_Msg_N ("invalid context for private declaration", N);
1035 New_Private_Type (N, Id, N);
1036 Set_Depends_On_Private (Id);
1037 end Analyze_Private_Type_Declaration;
1039 -------------------------------------------
1040 -- Declare_Inherited_Private_Subprograms --
1041 -------------------------------------------
1043 procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id) is
1047 Op_Elmt_2 : Elmt_Id;
1048 Prim_Op : Entity_Id;
1049 New_Op : Entity_Id := Empty;
1050 Parent_Subp : Entity_Id;
1051 Found_Explicit : Boolean;
1052 Decl_Privates : Boolean;
1054 function Has_Overriding_Pragma (Subp : Entity_Id) return Boolean;
1055 -- Check whether a pragma Overriding has been provided for a primitive
1056 -- operation that is found to be overriding in the private part.
1058 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean;
1059 -- Check whether an inherited subprogram is an operation of an
1060 -- untagged derived type.
1062 ---------------------------
1063 -- Has_Overriding_Pragma --
1064 ---------------------------
1066 function Has_Overriding_Pragma (Subp : Entity_Id) return Boolean is
1067 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
1072 or else Nkind (Decl) /= N_Subprogram_Declaration
1073 or else No (Next (Decl))
1078 Prag := Next (Decl);
1080 while Present (Prag)
1081 and then Nkind (Prag) = N_Pragma
1083 if Chars (Prag) = Name_Overriding
1084 or else Chars (Prag) = Name_Optional_Overriding
1094 end Has_Overriding_Pragma;
1096 ---------------------
1097 -- Is_Primitive_Of --
1098 ---------------------
1100 function Is_Primitive_Of (T : Entity_Id; S : Entity_Id) return Boolean is
1104 if Etype (S) = T then
1108 Formal := First_Formal (S);
1110 while Present (Formal) loop
1111 if Etype (Formal) = T then
1115 Next_Formal (Formal);
1120 end Is_Primitive_Of;
1122 -- Start of processing for Declare_Inherited_Private_Subprograms
1125 E := First_Entity (Id);
1126 while Present (E) loop
1128 -- If the entity is a nonprivate type extension whose parent
1129 -- type is declared in an open scope, then the type may have
1130 -- inherited operations that now need to be made visible.
1131 -- Ditto if the entity is a formal derived type in a child unit.
1133 if ((Is_Derived_Type (E) and then not Is_Private_Type (E))
1135 (Nkind (Parent (E)) = N_Private_Extension_Declaration
1136 and then Is_Generic_Type (E)))
1137 and then In_Open_Scopes (Scope (Etype (E)))
1138 and then E = Base_Type (E)
1140 if Is_Tagged_Type (E) then
1141 Op_List := Primitive_Operations (E);
1143 Decl_Privates := False;
1145 Op_Elmt := First_Elmt (Op_List);
1146 while Present (Op_Elmt) loop
1147 Prim_Op := Node (Op_Elmt);
1149 -- If the primitive operation is an implicit operation
1150 -- with an internal name whose parent operation has
1151 -- a normal name, then we now need to either declare the
1152 -- operation (i.e., make it visible), or replace it
1153 -- by an overriding operation if one exists.
1155 if Present (Alias (Prim_Op))
1156 and then not Comes_From_Source (Prim_Op)
1157 and then Is_Internal_Name (Chars (Prim_Op))
1158 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
1160 Parent_Subp := Alias (Prim_Op);
1162 Found_Explicit := False;
1163 Op_Elmt_2 := Next_Elmt (Op_Elmt);
1164 while Present (Op_Elmt_2) loop
1165 if Chars (Node (Op_Elmt_2)) = Chars (Parent_Subp)
1166 and then Type_Conformant (Prim_Op, Node (Op_Elmt_2))
1168 -- The private inherited operation has been
1169 -- overridden by an explicit subprogram, so
1170 -- change the private op's list element to
1171 -- designate the explicit so the explicit
1172 -- one will get the right dispatching slot.
1174 New_Op := Node (Op_Elmt_2);
1175 Replace_Elmt (Op_Elmt, New_Op);
1176 Remove_Elmt (Op_List, Op_Elmt_2);
1177 Found_Explicit := True;
1178 Decl_Privates := True;
1180 -- If explicit_overriding is in effect, check that
1181 -- the overriding operation is properly labelled.
1183 if Explicit_Overriding
1184 and then Comes_From_Source (New_Op)
1185 and then not Has_Overriding_Pragma (New_Op)
1188 ("Missing overriding pragma for&",
1195 Next_Elmt (Op_Elmt_2);
1198 if not Found_Explicit then
1200 (New_Op, Alias (Prim_Op), E, Etype (E));
1203 (Is_Dispatching_Operation (New_Op)
1204 and then Node (Last_Elmt (Op_List)) = New_Op);
1206 -- Substitute the new operation for the old one
1207 -- in the type's primitive operations list. Since
1208 -- the new operation was also just added to the end
1209 -- of list, the last element must be removed.
1211 -- (Question: is there a simpler way of declaring
1212 -- the operation, say by just replacing the name
1213 -- of the earlier operation, reentering it in the
1214 -- in the symbol table (how?), and marking it as
1217 Replace_Elmt (Op_Elmt, New_Op);
1218 Remove_Last_Elmt (Op_List);
1219 Decl_Privates := True;
1223 Next_Elmt (Op_Elmt);
1226 -- The type's DT attributes need to be recalculated
1227 -- in the case where private dispatching operations
1228 -- have been added or overridden. Normally this action
1229 -- occurs during type freezing, but we force it here
1230 -- since the type may already have been frozen (e.g.,
1231 -- if the type's package has an empty private part).
1232 -- This can only be done if expansion is active, otherwise
1233 -- Tag may not be present.
1236 and then Expander_Active
1238 Set_All_DT_Position (E);
1242 -- Non-tagged type, scan forward to locate
1243 -- inherited hidden operations.
1245 Prim_Op := Next_Entity (E);
1247 while Present (Prim_Op) loop
1248 if Is_Subprogram (Prim_Op)
1249 and then Present (Alias (Prim_Op))
1250 and then not Comes_From_Source (Prim_Op)
1251 and then Is_Internal_Name (Chars (Prim_Op))
1252 and then not Is_Internal_Name (Chars (Alias (Prim_Op)))
1253 and then Is_Primitive_Of (E, Prim_Op)
1255 Derive_Subprogram (New_Op, Alias (Prim_Op), E, Etype (E));
1258 Next_Entity (Prim_Op);
1265 end Declare_Inherited_Private_Subprograms;
1267 -----------------------
1268 -- End_Package_Scope --
1269 -----------------------
1271 procedure End_Package_Scope (P : Entity_Id) is
1273 Uninstall_Declarations (P);
1275 end End_Package_Scope;
1277 ---------------------------
1278 -- Exchange_Declarations --
1279 ---------------------------
1281 procedure Exchange_Declarations (Id : Entity_Id) is
1282 Full_Id : constant Entity_Id := Full_View (Id);
1283 H1 : constant Entity_Id := Homonym (Id);
1284 Next1 : constant Entity_Id := Next_Entity (Id);
1289 -- If missing full declaration for type, nothing to exchange
1291 if No (Full_Id) then
1295 -- Otherwise complete the exchange, and preserve semantic links
1297 Next2 := Next_Entity (Full_Id);
1298 H2 := Homonym (Full_Id);
1300 -- Reset full declaration pointer to reflect the switched entities
1301 -- and readjust the next entity chains.
1303 Exchange_Entities (Id, Full_Id);
1305 Set_Next_Entity (Id, Next1);
1306 Set_Homonym (Id, H1);
1308 Set_Full_View (Full_Id, Id);
1309 Set_Next_Entity (Full_Id, Next2);
1310 Set_Homonym (Full_Id, H2);
1311 end Exchange_Declarations;
1313 ----------------------------
1314 -- Install_Package_Entity --
1315 ----------------------------
1317 procedure Install_Package_Entity (Id : Entity_Id) is
1319 if not Is_Internal (Id) then
1320 if Debug_Flag_E then
1321 Write_Str ("Install: ");
1322 Write_Name (Chars (Id));
1326 if not Is_Child_Unit (Id) then
1327 Set_Is_Immediately_Visible (Id);
1331 end Install_Package_Entity;
1333 ----------------------------------
1334 -- Install_Private_Declarations --
1335 ----------------------------------
1337 procedure Install_Private_Declarations (P : Entity_Id) is
1339 Priv_Elmt : Elmt_Id;
1344 -- First exchange declarations for private types, so that the
1345 -- full declaration is visible. For each private type, we check
1346 -- its Private_Dependents list and also exchange any subtypes of
1347 -- or derived types from it. Finally, if this is a Taft amendment
1348 -- type, the incomplete declaration is irrelevant, and we want to
1349 -- link the eventual full declaration with the original private
1350 -- one so we also skip the exchange.
1352 Id := First_Entity (P);
1353 while Present (Id) and then Id /= First_Private_Entity (P) loop
1355 if Is_Private_Base_Type (Id)
1356 and then Comes_From_Source (Full_View (Id))
1357 and then Present (Full_View (Id))
1358 and then Scope (Full_View (Id)) = Scope (Id)
1359 and then Ekind (Full_View (Id)) /= E_Incomplete_Type
1361 -- If there is a use-type clause on the private type, set the
1362 -- full view accordingly.
1364 Set_In_Use (Full_View (Id), In_Use (Id));
1365 Full := Full_View (Id);
1367 if Is_Private_Base_Type (Full)
1368 and then Has_Private_Declaration (Full)
1369 and then Nkind (Parent (Full)) = N_Full_Type_Declaration
1370 and then In_Open_Scopes (Scope (Etype (Full)))
1371 and then In_Package_Body (Current_Scope)
1372 and then not Is_Private_Type (Etype (Full))
1374 -- This is the completion of a private type by a derivation
1375 -- from another private type which is not private anymore. This
1376 -- can only happen in a package nested within a child package,
1377 -- when the parent type is defined in the parent unit. At this
1378 -- point the current type is not private either, and we have to
1379 -- install the underlying full view, which is now visible.
1381 if No (Full_View (Full))
1382 and then Present (Underlying_Full_View (Full))
1384 Set_Full_View (Id, Underlying_Full_View (Full));
1385 Set_Underlying_Full_View (Full, Empty);
1386 Set_Is_Frozen (Full_View (Id));
1390 Priv_Elmt := First_Elmt (Private_Dependents (Id));
1392 Exchange_Declarations (Id);
1393 Set_Is_Immediately_Visible (Id);
1395 while Present (Priv_Elmt) loop
1396 Priv := Node (Priv_Elmt);
1398 -- Before the exchange, verify that the presence of the
1399 -- Full_View field. It will be empty if the entity
1400 -- has already been installed due to a previous call.
1402 if Present (Full_View (Priv))
1403 and then Is_Visible_Dependent (Priv)
1406 -- For each subtype that is swapped, we also swap the
1407 -- reference to it in Private_Dependents, to allow access
1408 -- to it when we swap them out in End_Package_Scope.
1410 Replace_Elmt (Priv_Elmt, Full_View (Priv));
1411 Exchange_Declarations (Priv);
1412 Set_Is_Immediately_Visible
1413 (Priv, In_Open_Scopes (Scope (Priv)));
1414 Set_Is_Potentially_Use_Visible
1415 (Priv, Is_Potentially_Use_Visible (Node (Priv_Elmt)));
1418 Next_Elmt (Priv_Elmt);
1425 -- Next make other declarations in the private part visible as well.
1427 Id := First_Private_Entity (P);
1429 while Present (Id) loop
1430 Install_Package_Entity (Id);
1434 -- Indicate that the private part is currently visible, so it can be
1435 -- properly reset on exit.
1437 Set_In_Private_Part (P);
1438 end Install_Private_Declarations;
1440 ----------------------------------
1441 -- Install_Visible_Declarations --
1442 ----------------------------------
1444 procedure Install_Visible_Declarations (P : Entity_Id) is
1448 Id := First_Entity (P);
1450 while Present (Id) and then Id /= First_Private_Entity (P) loop
1451 Install_Package_Entity (Id);
1454 end Install_Visible_Declarations;
1456 --------------------------
1457 -- Is_Private_Base_Type --
1458 --------------------------
1460 function Is_Private_Base_Type (E : Entity_Id) return Boolean is
1462 return Ekind (E) = E_Private_Type
1463 or else Ekind (E) = E_Limited_Private_Type
1464 or else Ekind (E) = E_Record_Type_With_Private;
1465 end Is_Private_Base_Type;
1467 --------------------------
1468 -- Is_Visible_Dependent --
1469 --------------------------
1471 function Is_Visible_Dependent (Dep : Entity_Id) return Boolean
1473 S : constant Entity_Id := Scope (Dep);
1476 -- Renamings created for actual types have the visibility of the
1479 if Ekind (S) = E_Package
1480 and then Is_Generic_Instance (S)
1481 and then (Is_Generic_Actual_Type (Dep)
1482 or else Is_Generic_Actual_Type (Full_View (Dep)))
1486 elsif not (Is_Derived_Type (Dep))
1487 and then Is_Derived_Type (Full_View (Dep))
1489 -- When instantiating a package body, the scope stack is empty,
1490 -- so check instead whether the dependent type is defined in
1491 -- the same scope as the instance itself.
1493 return In_Open_Scopes (S)
1494 or else (Is_Generic_Instance (Current_Scope)
1495 and then Scope (Dep) = Scope (Current_Scope));
1499 end Is_Visible_Dependent;
1501 ----------------------------
1502 -- May_Need_Implicit_Body --
1503 ----------------------------
1505 procedure May_Need_Implicit_Body (E : Entity_Id) is
1506 P : constant Node_Id := Unit_Declaration_Node (E);
1507 S : constant Node_Id := Parent (P);
1512 if not Has_Completion (E)
1513 and then Nkind (P) = N_Package_Declaration
1514 and then Present (Activation_Chain_Entity (P))
1517 Make_Package_Body (Sloc (E),
1518 Defining_Unit_Name => Make_Defining_Identifier (Sloc (E),
1519 Chars => Chars (E)),
1520 Declarations => New_List);
1522 if Nkind (S) = N_Package_Specification then
1523 if Present (Private_Declarations (S)) then
1524 Decls := Private_Declarations (S);
1526 Decls := Visible_Declarations (S);
1529 Decls := Declarations (S);
1535 end May_Need_Implicit_Body;
1537 ----------------------
1538 -- New_Private_Type --
1539 ----------------------
1541 procedure New_Private_Type (N : Node_Id; Id : Entity_Id; Def : Node_Id) is
1545 if Limited_Present (Def) then
1546 Set_Ekind (Id, E_Limited_Private_Type);
1548 Set_Ekind (Id, E_Private_Type);
1552 Set_Has_Delayed_Freeze (Id);
1553 Set_Is_First_Subtype (Id);
1554 Init_Size_Align (Id);
1556 Set_Is_Constrained (Id,
1557 No (Discriminant_Specifications (N))
1558 and then not Unknown_Discriminants_Present (N));
1560 -- Set tagged flag before processing discriminants, to catch
1563 Set_Is_Tagged_Type (Id, Tagged_Present (Def));
1565 Set_Discriminant_Constraint (Id, No_Elist);
1566 Set_Stored_Constraint (Id, No_Elist);
1568 if Present (Discriminant_Specifications (N)) then
1570 Process_Discriminants (N);
1573 elsif Unknown_Discriminants_Present (N) then
1574 Set_Has_Unknown_Discriminants (Id);
1577 Set_Private_Dependents (Id, New_Elmt_List);
1579 if Tagged_Present (Def) then
1580 Set_Ekind (Id, E_Record_Type_With_Private);
1581 Make_Class_Wide_Type (Id);
1582 Set_Primitive_Operations (Id, New_Elmt_List);
1583 Set_Is_Abstract (Id, Abstract_Present (Def));
1584 Set_Is_Limited_Record (Id, Limited_Present (Def));
1585 Set_Has_Delayed_Freeze (Id, True);
1587 elsif Abstract_Present (Def) then
1588 Error_Msg_N ("only a tagged type can be abstract", N);
1590 end New_Private_Type;
1592 ----------------------------
1593 -- Uninstall_Declarations --
1594 ----------------------------
1596 procedure Uninstall_Declarations (P : Entity_Id) is
1597 Decl : constant Node_Id := Unit_Declaration_Node (P);
1600 Priv_Elmt : Elmt_Id;
1601 Priv_Sub : Entity_Id;
1603 procedure Preserve_Full_Attributes (Priv, Full : Entity_Id);
1604 -- Copy to the private declaration the attributes of the full view
1605 -- that need to be available for the partial view also.
1607 function Type_In_Use (T : Entity_Id) return Boolean;
1608 -- Check whether type or base type appear in an active use_type clause.
1610 ------------------------------
1611 -- Preserve_Full_Attributes --
1612 ------------------------------
1614 procedure Preserve_Full_Attributes (Priv, Full : Entity_Id) is
1615 Priv_Is_Base_Type : constant Boolean := Priv = Base_Type (Priv);
1618 Set_Size_Info (Priv, (Full));
1619 Set_RM_Size (Priv, RM_Size (Full));
1620 Set_Size_Known_At_Compile_Time (Priv, Size_Known_At_Compile_Time
1622 Set_Is_Volatile (Priv, Is_Volatile (Full));
1623 Set_Treat_As_Volatile (Priv, Treat_As_Volatile (Full));
1625 if Referenced (Full) then
1626 Set_Referenced (Priv);
1629 if Priv_Is_Base_Type then
1630 Set_Is_Controlled (Priv, Is_Controlled (Base_Type (Full)));
1631 Set_Finalize_Storage_Only (Priv, Finalize_Storage_Only
1632 (Base_Type (Full)));
1633 Set_Has_Task (Priv, Has_Task (Base_Type (Full)));
1634 Set_Has_Controlled_Component (Priv, Has_Controlled_Component
1635 (Base_Type (Full)));
1638 Set_Freeze_Node (Priv, Freeze_Node (Full));
1640 if Is_Tagged_Type (Priv)
1641 and then Is_Tagged_Type (Full)
1642 and then not Error_Posted (Full)
1644 if Priv_Is_Base_Type then
1645 Set_Access_Disp_Table (Priv, Access_Disp_Table
1646 (Base_Type (Full)));
1649 Set_First_Entity (Priv, First_Entity (Full));
1650 Set_Last_Entity (Priv, Last_Entity (Full));
1651 Set_Has_Discriminants (Priv, Has_Discriminants (Full));
1653 end Preserve_Full_Attributes;
1659 function Type_In_Use (T : Entity_Id) return Boolean is
1661 return Scope (Base_Type (T)) = P
1662 and then (In_Use (T) or else In_Use (Base_Type (T)));
1665 -- Start of processing for Uninstall_Declarations
1668 Id := First_Entity (P);
1670 while Present (Id) and then Id /= First_Private_Entity (P) loop
1671 if Debug_Flag_E then
1672 Write_Str ("unlinking visible entity ");
1673 Write_Int (Int (Id));
1677 -- On exit from the package scope, we must preserve the visibility
1678 -- established by use clauses in the current scope. Two cases:
1680 -- a) If the entity is an operator, it may be a primitive operator of
1681 -- a type for which there is a visible use-type clause.
1683 -- b) for other entities, their use-visibility is determined by a
1684 -- visible use clause for the package itself. For a generic instance,
1685 -- the instantiation of the formals appears in the visible part,
1686 -- but the formals are private and remain so.
1688 if Ekind (Id) = E_Function
1689 and then Is_Operator_Symbol_Name (Chars (Id))
1690 and then not Is_Hidden (Id)
1691 and then not Error_Posted (Id)
1693 Set_Is_Potentially_Use_Visible (Id,
1695 or else Type_In_Use (Etype (Id))
1696 or else Type_In_Use (Etype (First_Formal (Id)))
1697 or else (Present (Next_Formal (First_Formal (Id)))
1700 (Etype (Next_Formal (First_Formal (Id))))));
1702 Set_Is_Potentially_Use_Visible (Id,
1703 In_Use (P) and not Is_Hidden (Id));
1706 -- Local entities are not immediately visible outside of the package.
1708 Set_Is_Immediately_Visible (Id, False);
1710 -- If this is a private type with a full view (for example a local
1711 -- subtype of a private type declared elsewhere), ensure that the
1712 -- full view is also removed from visibility: it may be exposed when
1713 -- swapping views in an instantiation.
1716 and then Present (Full_View (Id))
1718 Set_Is_Immediately_Visible (Full_View (Id), False);
1721 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
1722 Check_Abstract_Overriding (Id);
1725 if (Ekind (Id) = E_Private_Type
1726 or else Ekind (Id) = E_Limited_Private_Type)
1727 and then No (Full_View (Id))
1728 and then not Is_Generic_Type (Id)
1729 and then not Is_Derived_Type (Id)
1731 Error_Msg_N ("missing full declaration for private type&", Id);
1733 elsif Ekind (Id) = E_Record_Type_With_Private
1734 and then not Is_Generic_Type (Id)
1735 and then No (Full_View (Id))
1737 if Nkind (Parent (Id)) = N_Private_Type_Declaration then
1738 Error_Msg_N ("missing full declaration for private type&", Id);
1741 ("missing full declaration for private extension", Id);
1744 elsif Ekind (Id) = E_Constant
1745 and then No (Constant_Value (Id))
1746 and then No (Full_View (Id))
1747 and then not Is_Imported (Id)
1748 and then (Nkind (Parent (Id)) /= N_Object_Declaration
1749 or else not No_Initialization (Parent (Id)))
1751 if not Has_Private_Declaration (Etype (Id)) then
1753 -- We assume that the user did not not intend a deferred
1754 -- constant declaration, and the expression is just missing.
1757 ("constant declaration requires initialization expression",
1760 if Is_Limited_Type (Etype (Id)) then
1762 ("\else remove keyword CONSTANT from declaration",
1768 ("missing full declaration for deferred constant ('R'M 7.4)",
1771 if Is_Limited_Type (Etype (Id)) then
1773 ("\else remove keyword CONSTANT from declaration",
1782 -- If the specification was installed as the parent of a public child
1783 -- unit, the private declarations were not installed, and there is
1786 if not In_Private_Part (P) then
1789 Set_In_Private_Part (P, False);
1792 -- Make private entities invisible and exchange full and private
1793 -- declarations for private types.
1795 while Present (Id) loop
1796 if Debug_Flag_E then
1797 Write_Str ("unlinking private entity ");
1798 Write_Int (Int (Id));
1802 if Is_Tagged_Type (Id) and then Ekind (Id) = E_Record_Type then
1803 Check_Abstract_Overriding (Id);
1806 Set_Is_Immediately_Visible (Id, False);
1808 if Is_Private_Base_Type (Id)
1809 and then Present (Full_View (Id))
1811 Full := Full_View (Id);
1813 -- If the partial view is not declared in the visible part
1814 -- of the package (as is the case when it is a type derived
1815 -- from some other private type in the private part of the
1816 -- current package), no exchange takes place.
1819 or else List_Containing (Parent (Id))
1820 /= Visible_Declarations (Specification (Decl))
1825 -- The entry in the private part points to the full declaration,
1826 -- which is currently visible. Exchange them so only the private
1827 -- type declaration remains accessible, and link private and
1828 -- full declaration in the opposite direction. Before the actual
1829 -- exchange, we copy back attributes of the full view that
1830 -- must be available to the partial view too.
1832 Preserve_Full_Attributes (Id, Full);
1834 Set_Is_Potentially_Use_Visible (Id, In_Use (P));
1836 if Is_Indefinite_Subtype (Full)
1837 and then not Is_Indefinite_Subtype (Id)
1840 ("full view of type must be definite subtype", Full);
1843 Priv_Elmt := First_Elmt (Private_Dependents (Id));
1844 Exchange_Declarations (Id);
1846 -- Swap out the subtypes and derived types of Id that were
1847 -- compiled in this scope, or installed previously by
1848 -- Install_Private_Declarations.
1849 -- Before we do the swap, we verify the presence of the
1850 -- Full_View field which may be empty due to a swap by
1851 -- a previous call to End_Package_Scope (e.g. from the
1852 -- freezing mechanism).
1854 while Present (Priv_Elmt) loop
1855 Priv_Sub := Node (Priv_Elmt);
1857 if Present (Full_View (Priv_Sub)) then
1859 if Scope (Priv_Sub) = P
1860 or else not In_Open_Scopes (Scope (Priv_Sub))
1862 Set_Is_Immediately_Visible (Priv_Sub, False);
1865 if Is_Visible_Dependent (Priv_Sub) then
1866 Preserve_Full_Attributes
1867 (Priv_Sub, Full_View (Priv_Sub));
1868 Replace_Elmt (Priv_Elmt, Full_View (Priv_Sub));
1869 Exchange_Declarations (Priv_Sub);
1873 Next_Elmt (Priv_Elmt);
1876 elsif Ekind (Id) = E_Incomplete_Type
1877 and then No (Full_View (Id))
1879 -- Mark Taft amendment types
1881 Set_Has_Completion_In_Body (Id);
1883 elsif not Is_Child_Unit (Id)
1884 and then (not Is_Private_Type (Id)
1885 or else No (Full_View (Id)))
1888 Set_Is_Potentially_Use_Visible (Id, False);
1894 end Uninstall_Declarations;
1896 ------------------------
1897 -- Unit_Requires_Body --
1898 ------------------------
1900 function Unit_Requires_Body (P : Entity_Id) return Boolean is
1904 -- Imported entity never requires body. Right now, only
1905 -- subprograms can be imported, but perhaps in the future
1906 -- we will allow import of packages.
1908 if Is_Imported (P) then
1911 -- Body required if library package with pragma Elaborate_Body
1913 elsif Has_Pragma_Elaborate_Body (P) then
1916 -- Body required if subprogram
1918 elsif Is_Subprogram (P) or else Is_Generic_Subprogram (P) then
1921 -- Treat a block as requiring a body
1923 elsif Ekind (P) = E_Block then
1926 elsif Ekind (P) = E_Package
1927 and then Nkind (Parent (P)) = N_Package_Specification
1928 and then Present (Generic_Parent (Parent (P)))
1931 G_P : constant Entity_Id := Generic_Parent (Parent (P));
1934 if Has_Pragma_Elaborate_Body (G_P) then
1940 -- Otherwise search entity chain for entity requiring completion.
1942 E := First_Entity (P);
1943 while Present (E) loop
1945 -- Always ignore child units. Child units get added to the entity
1946 -- list of a parent unit, but are not original entities of the
1947 -- parent, and so do not affect whether the parent needs a body.
1949 if Is_Child_Unit (E) then
1952 -- Otherwise test to see if entity requires a completion
1954 elsif (Is_Overloadable (E)
1955 and then Ekind (E) /= E_Enumeration_Literal
1956 and then Ekind (E) /= E_Operator
1957 and then not Is_Abstract (E)
1958 and then not Has_Completion (E))
1961 (Ekind (E) = E_Package
1963 and then not Has_Completion (E)
1964 and then Unit_Requires_Body (E))
1967 (Ekind (E) = E_Incomplete_Type and then No (Full_View (E)))
1970 ((Ekind (E) = E_Task_Type or else
1971 Ekind (E) = E_Protected_Type)
1972 and then not Has_Completion (E))
1975 (Ekind (E) = E_Generic_Package and then E /= P
1976 and then not Has_Completion (E)
1977 and then Unit_Requires_Body (E))
1980 (Is_Generic_Subprogram (E)
1981 and then not Has_Completion (E))
1986 -- Entity that does not require completion
1996 end Unit_Requires_Body;