1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2006, 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, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, 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_Disp
; use Sem_Disp
;
54 with Sem_Util
; use Sem_Util
;
55 with Sem_Warn
; use Sem_Warn
;
56 with Snames
; use Snames
;
57 with Stand
; use Stand
;
58 with Sinfo
; use Sinfo
;
59 with Sinput
; use Sinput
;
62 package body Sem_Ch7
is
64 -----------------------------------
65 -- Handling private declarations --
66 -----------------------------------
68 -- The principle that each entity has a single defining occurrence clashes
69 -- with the presence of two separate definitions for private types: the
70 -- first is the private type declaration, and the second is the full type
71 -- declaration. It is important that all references to the type point to
72 -- the same defining occurrence, namely the first one. To enforce the two
73 -- separate views of the entity, the corresponding information is swapped
74 -- between the two declarations. Outside of the package, the defining
75 -- occurrence only contains the private declaration information, while in
76 -- the private part and the body of the package the defining occurrence
77 -- contains the full declaration. To simplify the swap, the defining
78 -- occurrence that currently holds the private declaration points to the
79 -- full declaration. During semantic processing the defining occurrence
80 -- also points to a list of private dependents, that is to say access types
81 -- or composite types whose designated types or component types are
82 -- subtypes or derived types of the private type in question. After the
83 -- full declaration has been seen, the private dependents are updated to
84 -- indicate that they have full definitions.
86 -----------------------
87 -- Local Subprograms --
88 -----------------------
90 procedure Check_Anonymous_Access_Types
93 -- If the spec of a package has a limited_with_clause, it may declare
94 -- anonymous access types whose designated type is a limited view, such
95 -- an anonymous access return type for a function. This access type
96 -- cannot be elaborated in the spec itself, but it may need an itype
97 -- reference if it is used within a nested scope. In that case the itype
98 -- reference is created at the beginning of the corresponding package body
99 -- and inserted before other body declarations.
101 procedure Install_Package_Entity
(Id
: Entity_Id
);
102 -- Basic procedure for the previous two. Places one entity on its
103 -- visibility chain, and recurses on the visible part if the entity
104 -- is an inner package.
106 function Is_Private_Base_Type
(E
: Entity_Id
) return Boolean;
107 -- True for a private type that is not a subtype
109 function Is_Visible_Dependent
(Dep
: Entity_Id
) return Boolean;
110 -- If the private dependent is a private type whose full view is derived
111 -- from the parent type, its full properties are revealed only if we are in
112 -- the immediate scope of the private dependent. Should this predicate be
113 -- tightened further???
115 procedure Declare_Inherited_Private_Subprograms
(Id
: Entity_Id
);
116 -- Called upon entering the private part of a public child package and the
117 -- body of a nested package, to potentially declare certain inherited
118 -- subprograms that were inherited by types in the visible part, but whose
119 -- declaration was deferred because the parent operation was private and
120 -- not visible at that point. These subprograms are located by traversing
121 -- the visible part declarations looking for non-private type extensions
122 -- and then examining each of the primitive operations of such types to
123 -- find those that were inherited but declared with a special internal
124 -- name. Each such operation is now declared as an operation with a normal
125 -- name (using the name of the parent operation) and replaces the previous
126 -- implicit operation in the primitive operations list of the type. If the
127 -- inherited private operation has been overridden, then it's replaced by
128 -- the overriding operation.
130 --------------------------
131 -- Analyze_Package_Body --
132 --------------------------
134 procedure Analyze_Package_Body
(N
: Node_Id
) is
135 Loc
: constant Source_Ptr
:= Sloc
(N
);
139 Last_Spec_Entity
: Entity_Id
;
143 procedure Install_Composite_Operations
(P
: Entity_Id
);
144 -- Composite types declared in the current scope may depend on
145 -- types that were private at the point of declaration, and whose
146 -- full view is now in scope. Indicate that the corresponding
147 -- operations on the composite type are available.
149 ----------------------------------
150 -- Install_Composite_Operations --
151 ----------------------------------
153 procedure Install_Composite_Operations
(P
: Entity_Id
) is
157 Id
:= First_Entity
(P
);
158 while Present
(Id
) loop
160 and then (Is_Limited_Composite
(Id
)
161 or else Is_Private_Composite
(Id
))
162 and then No
(Private_Component
(Id
))
164 Set_Is_Limited_Composite
(Id
, False);
165 Set_Is_Private_Composite
(Id
, False);
170 end Install_Composite_Operations
;
172 -- Start of processing for Analyze_Package_Body
175 -- Find corresponding package specification, and establish the
176 -- current scope. The visible defining entity for the package is the
177 -- defining occurrence in the spec. On exit from the package body, all
178 -- body declarations are attached to the defining entity for the body,
179 -- but the later is never used for name resolution. In this fashion
180 -- there is only one visible entity that denotes the package.
183 Write_Str
("==== Compiling package body ");
184 Write_Name
(Chars
(Defining_Entity
(N
)));
185 Write_Str
(" from ");
186 Write_Location
(Loc
);
190 -- Set Body_Id. Note that this Will be reset to point to the
191 -- generic copy later on in the generic case.
193 Body_Id
:= Defining_Entity
(N
);
195 if Present
(Corresponding_Spec
(N
)) then
197 -- Body is body of package instantiation. Corresponding spec
198 -- has already been set.
200 Spec_Id
:= Corresponding_Spec
(N
);
201 Pack_Decl
:= Unit_Declaration_Node
(Spec_Id
);
204 Spec_Id
:= Current_Entity_In_Scope
(Defining_Entity
(N
));
207 and then Is_Package_Or_Generic_Package
(Spec_Id
)
209 Pack_Decl
:= Unit_Declaration_Node
(Spec_Id
);
211 if Nkind
(Pack_Decl
) = N_Package_Renaming_Declaration
then
212 Error_Msg_N
("cannot supply body for package renaming", N
);
215 elsif Present
(Corresponding_Body
(Pack_Decl
)) then
216 Error_Msg_N
("redefinition of package body", N
);
221 Error_Msg_N
("missing specification for package body", N
);
225 if Is_Package_Or_Generic_Package
(Spec_Id
)
227 (Scope
(Spec_Id
) = Standard_Standard
228 or else Is_Child_Unit
(Spec_Id
))
229 and then not Unit_Requires_Body
(Spec_Id
)
231 if Ada_Version
= Ada_83
then
233 ("optional package body (not allowed in Ada 95)?", N
);
236 ("spec of this package does not allow a body", N
);
241 Set_Is_Compilation_Unit
(Body_Id
, Is_Compilation_Unit
(Spec_Id
));
242 Style
.Check_Identifier
(Body_Id
, Spec_Id
);
244 if Is_Child_Unit
(Spec_Id
) then
245 if Nkind
(Parent
(N
)) /= N_Compilation_Unit
then
247 ("body of child unit& cannot be an inner package", N
, Spec_Id
);
250 Set_Is_Child_Unit
(Body_Id
);
253 -- Generic package case
255 if Ekind
(Spec_Id
) = E_Generic_Package
then
257 -- Disable expansion and perform semantic analysis on copy.
258 -- The unannotated body will be used in all instantiations.
260 Body_Id
:= Defining_Entity
(N
);
261 Set_Ekind
(Body_Id
, E_Package_Body
);
262 Set_Scope
(Body_Id
, Scope
(Spec_Id
));
263 Set_Is_Obsolescent
(Body_Id
, Is_Obsolescent
(Spec_Id
));
264 Set_Body_Entity
(Spec_Id
, Body_Id
);
265 Set_Spec_Entity
(Body_Id
, Spec_Id
);
267 New_N
:= Copy_Generic_Node
(N
, Empty
, Instantiating
=> False);
270 -- Update Body_Id to point to the copied node for the remainder
271 -- of the processing.
273 Body_Id
:= Defining_Entity
(N
);
277 -- The Body_Id is that of the copied node in the generic case, the
278 -- current node otherwise. Note that N was rewritten above, so we
279 -- must be sure to get the latest Body_Id value.
281 Set_Ekind
(Body_Id
, E_Package_Body
);
282 Set_Body_Entity
(Spec_Id
, Body_Id
);
283 Set_Spec_Entity
(Body_Id
, Spec_Id
);
285 -- Defining name for the package body is not a visible entity: Only
286 -- the defining name for the declaration is visible.
288 Set_Etype
(Body_Id
, Standard_Void_Type
);
289 Set_Scope
(Body_Id
, Scope
(Spec_Id
));
290 Set_Corresponding_Spec
(N
, Spec_Id
);
291 Set_Corresponding_Body
(Pack_Decl
, Body_Id
);
293 -- The body entity is not used for semantics or code generation, but
294 -- it is attached to the entity list of the enclosing scope to simplify
295 -- the listing of back-annotations for the types it main contain.
297 if Scope
(Spec_Id
) /= Standard_Standard
then
298 Append_Entity
(Body_Id
, Scope
(Spec_Id
));
301 -- Indicate that we are currently compiling the body of the package
303 Set_In_Package_Body
(Spec_Id
);
304 Set_Has_Completion
(Spec_Id
);
305 Last_Spec_Entity
:= Last_Entity
(Spec_Id
);
309 Set_Categorization_From_Pragmas
(N
);
311 Install_Visible_Declarations
(Spec_Id
);
312 Install_Private_Declarations
(Spec_Id
);
313 Install_Private_With_Clauses
(Spec_Id
);
314 Install_Composite_Operations
(Spec_Id
);
316 Check_Anonymous_Access_Types
(Spec_Id
, N
);
318 if Ekind
(Spec_Id
) = E_Generic_Package
then
319 Set_Use
(Generic_Formal_Declarations
(Pack_Decl
));
322 Set_Use
(Visible_Declarations
(Specification
(Pack_Decl
)));
323 Set_Use
(Private_Declarations
(Specification
(Pack_Decl
)));
325 -- This is a nested package, so it may be necessary to declare
326 -- certain inherited subprograms that are not yet visible because
327 -- the parent type's subprograms are now visible.
329 if Ekind
(Scope
(Spec_Id
)) = E_Package
330 and then Scope
(Spec_Id
) /= Standard_Standard
332 Declare_Inherited_Private_Subprograms
(Spec_Id
);
335 if Present
(Declarations
(N
)) then
336 Analyze_Declarations
(Declarations
(N
));
339 HSS
:= Handled_Statement_Sequence
(N
);
341 if Present
(HSS
) then
342 Process_End_Label
(HSS
, 't', Spec_Id
);
345 -- Check that elaboration code in a preelaborable package body is
346 -- empty other than null statements and labels (RM 10.2.1(6)).
348 Validate_Null_Statement_Sequence
(N
);
351 Validate_Categorization_Dependency
(N
, Spec_Id
);
352 Check_Completion
(Body_Id
);
354 -- Generate start of body reference. Note that we do this fairly late,
355 -- because the call will use In_Extended_Main_Source_Unit as a check,
356 -- and we want to make sure that Corresponding_Stub links are set
358 Generate_Reference
(Spec_Id
, Body_Id
, 'b', Set_Ref
=> False);
360 -- For a generic package, collect global references and mark them on
361 -- the original body so that they are not resolved again at the point
364 if Ekind
(Spec_Id
) /= E_Package
then
365 Save_Global_References
(Original_Node
(N
));
369 -- The entities of the package body have so far been chained onto the
370 -- declaration chain for the spec. That's been fine while we were in the
371 -- body, since we wanted them to be visible, but now that we are leaving
372 -- the package body, they are no longer visible, so we remove them from
373 -- the entity chain of the package spec entity, and copy them to the
374 -- entity chain of the package body entity, where they will never again
377 if Present
(Last_Spec_Entity
) then
378 Set_First_Entity
(Body_Id
, Next_Entity
(Last_Spec_Entity
));
379 Set_Next_Entity
(Last_Spec_Entity
, Empty
);
380 Set_Last_Entity
(Body_Id
, Last_Entity
(Spec_Id
));
381 Set_Last_Entity
(Spec_Id
, Last_Spec_Entity
);
384 Set_First_Entity
(Body_Id
, First_Entity
(Spec_Id
));
385 Set_Last_Entity
(Body_Id
, Last_Entity
(Spec_Id
));
386 Set_First_Entity
(Spec_Id
, Empty
);
387 Set_Last_Entity
(Spec_Id
, Empty
);
390 End_Package_Scope
(Spec_Id
);
392 -- All entities declared in body are not visible
398 E
:= First_Entity
(Body_Id
);
399 while Present
(E
) loop
400 Set_Is_Immediately_Visible
(E
, False);
401 Set_Is_Potentially_Use_Visible
(E
, False);
404 -- Child units may appear on the entity list (for example if
405 -- they appear in the context of a subunit) but they are not
408 if not Is_Child_Unit
(E
) then
409 Set_Is_Package_Body_Entity
(E
);
416 Check_References
(Body_Id
);
418 -- For a generic unit, check that the formal parameters are referenced,
419 -- and that local variables are used, as for regular packages.
421 if Ekind
(Spec_Id
) = E_Generic_Package
then
422 Check_References
(Spec_Id
);
425 -- The processing so far has made all entities of the package body
426 -- public (i.e. externally visible to the linker). This is in general
427 -- necessary, since inlined or generic bodies, for which code is
428 -- generated in other units, may need to see these entities. The
429 -- following loop runs backwards from the end of the entities of the
430 -- package body making these entities invisible until we reach a
431 -- referencer, i.e. a declaration that could reference a previous
432 -- declaration, a generic body or an inlined body, or a stub (which
433 -- may contain either of these). This is of course an approximation,
434 -- but it is conservative and definitely correct.
436 -- We only do this at the outer (library) level non-generic packages.
437 -- The reason is simply to cut down on the number of external symbols
438 -- generated, so this is simply an optimization of the efficiency
439 -- of the compilation process. It has no other effect.
441 if (Scope
(Spec_Id
) = Standard_Standard
or else Is_Child_Unit
(Spec_Id
))
442 and then not Is_Generic_Unit
(Spec_Id
)
443 and then Present
(Declarations
(N
))
445 Make_Non_Public_Where_Possible
: declare
447 function Has_Referencer
451 -- Traverse the given list of declarations in reverse order.
452 -- Return True as soon as a referencer is reached. Return
453 -- False if none is found. The Outer parameter is True for
454 -- the outer level call, and False for inner level calls for
455 -- nested packages. If Outer is True, then any entities up
456 -- to the point of hitting a referencer get their Is_Public
457 -- flag cleared, so that the entities will be treated as
458 -- static entities in the C sense, and need not have fully
459 -- qualified names. For inner levels, we need all names to
460 -- be fully qualified to deal with the same name appearing
461 -- in parallel packages (right now this is tied to their
468 function Has_Referencer
484 while Present
(D
) loop
487 if K
in N_Body_Stub
then
490 elsif K
= N_Subprogram_Body
then
491 if Acts_As_Spec
(D
) then
492 E
:= Defining_Entity
(D
);
494 -- An inlined body acts as a referencer. Note also
495 -- that we never reset Is_Public for an inlined
496 -- subprogram. Gigi requires Is_Public to be set.
498 -- Note that we test Has_Pragma_Inline here rather
499 -- than Is_Inlined. We are compiling this for a
500 -- client, and it is the client who will decide
501 -- if actual inlining should occur, so we need to
502 -- assume that the procedure could be inlined for
503 -- the purpose of accessing global entities.
505 if Has_Pragma_Inline
(E
) then
508 Set_Is_Public
(E
, False);
512 E
:= Corresponding_Spec
(D
);
515 and then (Is_Generic_Unit
(E
)
516 or else Has_Pragma_Inline
(E
)
517 or else Is_Inlined
(E
))
523 -- Processing for package bodies
525 elsif K
= N_Package_Body
526 and then Present
(Corresponding_Spec
(D
))
528 E
:= Corresponding_Spec
(D
);
530 -- Generic package body is a referencer. It would
531 -- seem that we only have to consider generics that
532 -- can be exported, i.e. where the corresponding spec
533 -- is the spec of the current package, but because of
534 -- nested instantiations, a fully private generic
535 -- body may export other private body entities.
537 if Is_Generic_Unit
(E
) then
540 -- For non-generic package body, recurse into body
541 -- unless this is an instance, we ignore instances
542 -- since they cannot have references that affect
545 elsif not Is_Generic_Instance
(E
) then
547 (Declarations
(D
), Outer
=> False)
553 -- Processing for package specs, recurse into declarations.
554 -- Again we skip this for the case of generic instances.
556 elsif K
= N_Package_Declaration
then
557 S
:= Specification
(D
);
559 if not Is_Generic_Unit
(Defining_Entity
(S
)) then
561 (Private_Declarations
(S
), Outer
=> False)
565 (Visible_Declarations
(S
), Outer
=> False)
571 -- Objects and exceptions need not be public if we have
572 -- not encountered a referencer so far. We only reset
573 -- the flag for outer level entities that are not
574 -- imported/exported, and which have no interface name.
576 elsif K
= N_Object_Declaration
577 or else K
= N_Exception_Declaration
578 or else K
= N_Subprogram_Declaration
580 E
:= Defining_Entity
(D
);
583 and then not Is_Imported
(E
)
584 and then not Is_Exported
(E
)
585 and then No
(Interface_Name
(E
))
587 Set_Is_Public
(E
, False);
597 -- Start of processing for Make_Non_Public_Where_Possible
602 pragma Warnings
(Off
, Discard
);
605 Discard
:= Has_Referencer
(Declarations
(N
), Outer
=> True);
607 end Make_Non_Public_Where_Possible
;
610 -- If expander is not active, then here is where we turn off the
611 -- In_Package_Body flag, otherwise it is turned off at the end of
612 -- the corresponding expansion routine. If this is an instance body,
613 -- we need to qualify names of local entities, because the body may
614 -- have been compiled as a preliminary to another instantiation.
616 if not Expander_Active
then
617 Set_In_Package_Body
(Spec_Id
, False);
619 if Is_Generic_Instance
(Spec_Id
)
620 and then Operating_Mode
= Generate_Code
622 Qualify_Entity_Names
(N
);
625 end Analyze_Package_Body
;
627 ---------------------------------
628 -- Analyze_Package_Declaration --
629 ---------------------------------
631 procedure Analyze_Package_Declaration
(N
: Node_Id
) is
632 Id
: constant Node_Id
:= Defining_Entity
(N
);
636 -- Ada 2005 (AI-217): Check if the package has been erroneously named
637 -- in a limited-with clause of its own context. In this case the error
638 -- has been previously notified by Analyze_Context.
640 -- limited with Pkg; -- ERROR
641 -- package Pkg is ...
643 if From_With_Type
(Id
) then
647 Generate_Definition
(Id
);
649 Set_Ekind
(Id
, E_Package
);
650 Set_Etype
(Id
, Standard_Void_Type
);
654 PF
:= Is_Pure
(Enclosing_Lib_Unit_Entity
);
655 Set_Is_Pure
(Id
, PF
);
657 Set_Categorization_From_Pragmas
(N
);
660 Write_Str
("==== Compiling package spec ");
661 Write_Name
(Chars
(Id
));
662 Write_Str
(" from ");
663 Write_Location
(Sloc
(N
));
667 Analyze
(Specification
(N
));
668 Validate_Categorization_Dependency
(N
, Id
);
669 End_Package_Scope
(Id
);
671 -- For a compilation unit, indicate whether it needs a body, and
672 -- whether elaboration warnings may be meaningful on it.
674 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
675 Set_Body_Required
(Parent
(N
), Unit_Requires_Body
(Id
));
677 if not Body_Required
(Parent
(N
)) then
678 Set_Suppress_Elaboration_Warnings
(Id
);
681 Validate_RT_RAT_Component
(N
);
683 end Analyze_Package_Declaration
;
685 -----------------------------------
686 -- Analyze_Package_Specification --
687 -----------------------------------
689 -- Note that this code is shared for the analysis of generic package
690 -- specs (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).
692 procedure Analyze_Package_Specification
(N
: Node_Id
) is
693 Id
: constant Entity_Id
:= Defining_Entity
(N
);
694 Orig_Decl
: constant Node_Id
:= Original_Node
(Parent
(N
));
695 Vis_Decls
: constant List_Id
:= Visible_Declarations
(N
);
696 Priv_Decls
: constant List_Id
:= Private_Declarations
(N
);
699 Public_Child
: Boolean;
701 Private_With_Clauses_Installed
: Boolean := False;
702 -- In Ada 2005, private with_clauses are visible in the private part
703 -- of a nested package, even if it appears in the public part of the
704 -- enclosing package. This requires a separate step to install these
705 -- private_with_clauses, and remove them at the end of the nested
708 procedure Clear_Constants
(Id
: Entity_Id
; FE
: Entity_Id
);
709 -- Clears constant indications (Never_Set_In_Source, Constant_Value,
710 -- and Is_True_Constant) on all variables that are entities of Id,
711 -- and on the chain whose first element is FE. A recursive call is
712 -- made for all packages and generic packages.
714 procedure Generate_Parent_References
;
715 -- For a child unit, generate references to parent units, for
716 -- GPS navigation purposes.
718 function Is_Public_Child
(Child
, Unit
: Entity_Id
) return Boolean;
719 -- Child and Unit are entities of compilation units. True if Child
720 -- is a public child of Parent as defined in 10.1.1
722 procedure Inspect_Deferred_Constant_Completion
;
723 -- Examines the deferred constants in the private part of the package
724 -- specification. Emits the error message "constant declaration requires
725 -- initialization expression " if not completed by an Import pragma.
727 procedure Inspect_Unchecked_Union_Completion
(Decls
: List_Id
);
728 -- Detects all incomplete or private type declarations having a known
729 -- discriminant part that are completed by an Unchecked_Union. Emits
730 -- the error message "Unchecked_Union may not complete discriminated
733 procedure Install_Parent_Private_Declarations
(Inst_Id
: Entity_Id
);
734 -- Given the package entity of a generic package instantiation or
735 -- formal package whose corresponding generic is a child unit, installs
736 -- the private declarations of each of the child unit's parents.
737 -- This has to be done at the point of entering the instance package's
738 -- private part rather than being done in Sem_Ch12.Install_Parent
739 -- (which is where the parents' visible declarations are installed).
741 ---------------------
742 -- Clear_Constants --
743 ---------------------
745 procedure Clear_Constants
(Id
: Entity_Id
; FE
: Entity_Id
) is
749 -- Ignore package renamings, not interesting and they can
750 -- cause self referential loops in the code below.
752 if Nkind
(Parent
(Id
)) = N_Package_Renaming_Declaration
then
756 -- Note: in the loop below, the check for Next_Entity pointing
757 -- back to the package entity may seem odd, but it is needed,
758 -- because a package can contain a renaming declaration to itself,
759 -- and such renamings are generated automatically within package
763 while Present
(E
) and then E
/= Id
loop
764 if Ekind
(E
) = E_Variable
then
765 Set_Never_Set_In_Source
(E
, False);
766 Set_Is_True_Constant
(E
, False);
767 Set_Current_Value
(E
, Empty
);
768 Set_Is_Known_Null
(E
, False);
769 Set_Last_Assignment
(E
, Empty
);
771 if not Can_Never_Be_Null
(E
) then
772 Set_Is_Known_Non_Null
(E
, False);
775 elsif Ekind
(E
) = E_Package
777 Ekind
(E
) = E_Generic_Package
779 Clear_Constants
(E
, First_Entity
(E
));
780 Clear_Constants
(E
, First_Private_Entity
(E
));
787 --------------------------------
788 -- Generate_Parent_References --
789 --------------------------------
791 procedure Generate_Parent_References
is
792 Decl
: constant Node_Id
:= Parent
(N
);
795 if Id
= Cunit_Entity
(Main_Unit
)
796 or else Parent
(Decl
) = Library_Unit
(Cunit
(Main_Unit
))
798 Generate_Reference
(Id
, Scope
(Id
), 'k', False);
800 elsif Nkind
(Unit
(Cunit
(Main_Unit
))) /= N_Subprogram_Body
801 and then Nkind
(Unit
(Cunit
(Main_Unit
))) /= N_Subunit
803 -- If current unit is an ancestor of main unit, generate
804 -- a reference to its own parent.
808 Main_Spec
: Node_Id
:= Unit
(Cunit
(Main_Unit
));
811 if Nkind
(Main_Spec
) = N_Package_Body
then
812 Main_Spec
:= Unit
(Library_Unit
(Cunit
(Main_Unit
)));
815 U
:= Parent_Spec
(Main_Spec
);
816 while Present
(U
) loop
817 if U
= Parent
(Decl
) then
818 Generate_Reference
(Id
, Scope
(Id
), 'k', False);
821 elsif Nkind
(Unit
(U
)) = N_Package_Body
then
825 U
:= Parent_Spec
(Unit
(U
));
830 end Generate_Parent_References
;
832 ---------------------
833 -- Is_Public_Child --
834 ---------------------
836 function Is_Public_Child
(Child
, Unit
: Entity_Id
) return Boolean is
838 if not Is_Private_Descendant
(Child
) then
842 return not Private_Present
(
843 Parent
(Unit_Declaration_Node
(Child
)));
845 return Is_Public_Child
(Scope
(Child
), Unit
);
850 ------------------------------------------
851 -- Inspect_Deferred_Constant_Completion --
852 ------------------------------------------
854 procedure Inspect_Deferred_Constant_Completion
is
858 Decl
:= First
(Priv_Decls
);
859 while Present
(Decl
) loop
861 -- Deferred constant signature
863 if Nkind
(Decl
) = N_Object_Declaration
864 and then Constant_Present
(Decl
)
865 and then No
(Expression
(Decl
))
867 -- No need to check internally generated constants
869 and then Comes_From_Source
(Decl
)
871 -- The constant is not completed. A full object declaration
872 -- or a pragma Import complete a deferred constant.
874 and then not Has_Completion
(Defining_Identifier
(Decl
))
877 ("constant declaration requires initialization expression",
878 Defining_Identifier
(Decl
));
883 end Inspect_Deferred_Constant_Completion
;
885 ----------------------------------------
886 -- Inspect_Unchecked_Union_Completion --
887 ----------------------------------------
889 procedure Inspect_Unchecked_Union_Completion
(Decls
: List_Id
) is
893 Decl
:= First
(Decls
);
894 while Present
(Decl
) loop
896 -- We are looking at an incomplete or private type declaration
897 -- with a known_discriminant_part whose full view is an
900 if (Nkind
(Decl
) = N_Incomplete_Type_Declaration
902 Nkind
(Decl
) = N_Private_Type_Declaration
)
903 and then Has_Discriminants
(Defining_Identifier
(Decl
))
904 and then Present
(Full_View
(Defining_Identifier
(Decl
)))
905 and then Is_Unchecked_Union
906 (Full_View
(Defining_Identifier
(Decl
)))
908 Error_Msg_N
("completion of discriminated partial view" &
909 " cannot be an Unchecked_Union",
910 Full_View
(Defining_Identifier
(Decl
)));
915 end Inspect_Unchecked_Union_Completion
;
917 -----------------------------------------
918 -- Install_Parent_Private_Declarations --
919 -----------------------------------------
921 procedure Install_Parent_Private_Declarations
(Inst_Id
: Entity_Id
) is
922 Inst_Par
: Entity_Id
;
929 Generic_Parent
(Specification
(Unit_Declaration_Node
(Inst_Par
)));
930 while Present
(Gen_Par
) and then Is_Child_Unit
(Gen_Par
) loop
931 Inst_Node
:= Get_Package_Instantiation_Node
(Inst_Par
);
933 if (Nkind
(Inst_Node
) = N_Package_Instantiation
934 or else Nkind
(Inst_Node
) = N_Formal_Package_Declaration
)
935 and then Nkind
(Name
(Inst_Node
)) = N_Expanded_Name
937 Inst_Par
:= Entity
(Prefix
(Name
(Inst_Node
)));
939 if Present
(Renamed_Entity
(Inst_Par
)) then
940 Inst_Par
:= Renamed_Entity
(Inst_Par
);
945 (Specification
(Unit_Declaration_Node
(Inst_Par
)));
947 -- Install the private declarations and private use clauses
948 -- of a parent instance of the child instance, unless the
949 -- parent instance private declarations have already been
950 -- installed earlier in Analyze_Package_Specification, which
951 -- happens when a generic child is instantiated, and the
952 -- instance is a child of the parent instance.
954 -- Installing the use clauses of the parent instance twice is
955 -- both unnecessary and wrong, because it would cause the
956 -- clauses to be chained to themselves in the use clauses list
957 -- of the scope stack entry. That in turn would cause
958 -- End_Use_Clauses to get into an endless look upon scope exit.
960 if Present
(Gen_Par
) then
961 if not In_Private_Part
(Inst_Par
) then
962 Install_Private_Declarations
(Inst_Par
);
963 Set_Use
(Private_Declarations
965 (Unit_Declaration_Node
(Inst_Par
))));
968 -- If we've reached the end of the generic instance parents,
969 -- then finish off by looping through the nongeneric parents
970 -- and installing their private declarations.
973 while Present
(Inst_Par
)
974 and then Inst_Par
/= Standard_Standard
975 and then (not In_Open_Scopes
(Inst_Par
)
976 or else not In_Private_Part
(Inst_Par
))
978 Install_Private_Declarations
(Inst_Par
);
979 Set_Use
(Private_Declarations
981 (Unit_Declaration_Node
(Inst_Par
))));
982 Inst_Par
:= Scope
(Inst_Par
);
992 end Install_Parent_Private_Declarations
;
994 -- Start of processing for Analyze_Package_Specification
997 if Present
(Vis_Decls
) then
998 Analyze_Declarations
(Vis_Decls
);
1001 -- Verify that incomplete types have received full declarations
1003 E
:= First_Entity
(Id
);
1004 while Present
(E
) loop
1005 if Ekind
(E
) = E_Incomplete_Type
1006 and then No
(Full_View
(E
))
1008 Error_Msg_N
("no declaration in visible part for incomplete}", E
);
1014 if Is_Remote_Call_Interface
(Id
)
1015 and then Nkind
(Parent
(Parent
(N
))) = N_Compilation_Unit
1017 Validate_RCI_Declarations
(Id
);
1020 -- Save global references in the visible declarations, before
1021 -- installing private declarations of parent unit if there is one,
1022 -- because the privacy status of types defined in the parent will
1023 -- change. This is only relevant for generic child units, but is
1024 -- done in all cases for uniformity.
1026 if Ekind
(Id
) = E_Generic_Package
1027 and then Nkind
(Orig_Decl
) = N_Generic_Package_Declaration
1030 Orig_Spec
: constant Node_Id
:= Specification
(Orig_Decl
);
1031 Save_Priv
: constant List_Id
:= Private_Declarations
(Orig_Spec
);
1034 Set_Private_Declarations
(Orig_Spec
, Empty_List
);
1035 Save_Global_References
(Orig_Decl
);
1036 Set_Private_Declarations
(Orig_Spec
, Save_Priv
);
1040 -- If package is a public child unit, then make the private declarations
1041 -- of the parent visible.
1043 Public_Child
:= False;
1047 Pack_Decl
: Node_Id
;
1052 Par_Spec
:= Parent_Spec
(Parent
(N
));
1054 -- If the package is formal package of an enclosing generic, it is
1055 -- transformed into a local generic declaration, and compiled to make
1056 -- its spec available. We need to retrieve the original generic to
1057 -- determine whether it is a child unit, and install its parents.
1061 Nkind
(Original_Node
(Parent
(N
))) = N_Formal_Package_Declaration
1063 Par
:= Entity
(Name
(Original_Node
(Parent
(N
))));
1064 Par_Spec
:= Parent_Spec
(Unit_Declaration_Node
(Par
));
1067 if Present
(Par_Spec
) then
1068 Generate_Parent_References
;
1070 while Scope
(Par
) /= Standard_Standard
1071 and then Is_Public_Child
(Id
, Par
)
1072 and then In_Open_Scopes
(Par
)
1074 Public_Child
:= True;
1076 Install_Private_Declarations
(Par
);
1077 Install_Private_With_Clauses
(Par
);
1078 Pack_Decl
:= Unit_Declaration_Node
(Par
);
1079 Set_Use
(Private_Declarations
(Specification
(Pack_Decl
)));
1084 if Is_Compilation_Unit
(Id
) then
1085 Install_Private_With_Clauses
(Id
);
1088 -- The current compilation unit may include private with_clauses,
1089 -- which are visible in the private part of the current nested
1090 -- package, and have to be installed now.
1093 Comp_Unit
: constant Entity_Id
:= Cunit_Entity
(Current_Sem_Unit
);
1095 if (Ekind
(Comp_Unit
) = E_Package
1096 or else Ekind
(Comp_Unit
) = E_Generic_Package
)
1097 and then not In_Private_Part
(Comp_Unit
)
1099 Install_Private_With_Clauses
(Comp_Unit
);
1100 Private_With_Clauses_Installed
:= True;
1105 -- If this is a package associated with a generic instance or formal
1106 -- package, then the private declarations of each of the generic's
1107 -- parents must be installed at this point.
1109 if Is_Generic_Instance
(Id
) then
1110 Install_Parent_Private_Declarations
(Id
);
1113 -- Analyze private part if present. The flag In_Private_Part is reset
1114 -- in End_Package_Scope.
1116 L
:= Last_Entity
(Id
);
1118 if Present
(Priv_Decls
) then
1119 Set_In_Private_Part
(Id
);
1121 -- Upon entering a public child's private part, it may be necessary
1122 -- to declare subprograms that were derived in the package's visible
1123 -- part but not yet made visible.
1125 if Public_Child
then
1126 Declare_Inherited_Private_Subprograms
(Id
);
1129 Analyze_Declarations
(Priv_Decls
);
1131 -- Check the private declarations for incomplete deferred constants
1133 Inspect_Deferred_Constant_Completion
;
1135 -- The first private entity is the immediate follower of the last
1136 -- visible entity, if there was one.
1139 Set_First_Private_Entity
(Id
, Next_Entity
(L
));
1141 Set_First_Private_Entity
(Id
, First_Entity
(Id
));
1144 -- There may be inherited private subprograms that need to be declared,
1145 -- even in the absence of an explicit private part. If there are any
1146 -- public declarations in the package and the package is a public child
1147 -- unit, then an implicit private part is assumed.
1149 elsif Present
(L
) and then Public_Child
then
1150 Set_In_Private_Part
(Id
);
1151 Declare_Inherited_Private_Subprograms
(Id
);
1152 Set_First_Private_Entity
(Id
, Next_Entity
(L
));
1155 -- Check rule of 3.6(11), which in general requires waiting till all
1156 -- full types have been seen.
1158 E
:= First_Entity
(Id
);
1159 while Present
(E
) loop
1160 if Ekind
(E
) = E_Record_Type
or else Ekind
(E
) = E_Array_Type
then
1161 Check_Aliased_Component_Types
(E
);
1167 -- Ada 2005 (AI-216): The completion of an incomplete or private type
1168 -- declaration having a known_discriminant_part shall not be an
1169 -- Unchecked_Union type.
1171 if Present
(Vis_Decls
) then
1172 Inspect_Unchecked_Union_Completion
(Vis_Decls
);
1175 if Present
(Priv_Decls
) then
1176 Inspect_Unchecked_Union_Completion
(Priv_Decls
);
1179 if Ekind
(Id
) = E_Generic_Package
1180 and then Nkind
(Orig_Decl
) = N_Generic_Package_Declaration
1181 and then Present
(Priv_Decls
)
1183 -- Save global references in private declarations, ignoring the
1184 -- visible declarations that were processed earlier.
1187 Orig_Spec
: constant Node_Id
:= Specification
(Orig_Decl
);
1188 Save_Vis
: constant List_Id
:= Visible_Declarations
(Orig_Spec
);
1189 Save_Form
: constant List_Id
:=
1190 Generic_Formal_Declarations
(Orig_Decl
);
1193 Set_Visible_Declarations
(Orig_Spec
, Empty_List
);
1194 Set_Generic_Formal_Declarations
(Orig_Decl
, Empty_List
);
1195 Save_Global_References
(Orig_Decl
);
1196 Set_Generic_Formal_Declarations
(Orig_Decl
, Save_Form
);
1197 Set_Visible_Declarations
(Orig_Spec
, Save_Vis
);
1201 Process_End_Label
(N
, 'e', Id
);
1203 -- Remove private_with_clauses of enclosing compilation unit, if they
1206 if Private_With_Clauses_Installed
then
1207 Remove_Private_With_Clauses
(Cunit
(Current_Sem_Unit
));
1210 -- For the case of a library level package, we must go through all the
1211 -- entities clearing the indications that the value may be constant and
1212 -- not modified. Why? Because any client of this package may modify
1213 -- these values freely from anywhere. This also applies to any nested
1214 -- packages or generic packages.
1216 -- For now we unconditionally clear constants for packages that are
1217 -- instances of generic packages. The reason is that we do not have the
1218 -- body yet, and we otherwise think things are unreferenced when they
1219 -- are not. This should be fixed sometime (the effect is not terrible,
1220 -- we just lose some warnings, and also some cases of value propagation)
1223 if Is_Library_Level_Entity
(Id
)
1224 or else Is_Generic_Instance
(Id
)
1226 Clear_Constants
(Id
, First_Entity
(Id
));
1227 Clear_Constants
(Id
, First_Private_Entity
(Id
));
1229 end Analyze_Package_Specification
;
1231 --------------------------------------
1232 -- Analyze_Private_Type_Declaration --
1233 --------------------------------------
1235 procedure Analyze_Private_Type_Declaration
(N
: Node_Id
) is
1236 PF
: constant Boolean := Is_Pure
(Enclosing_Lib_Unit_Entity
);
1237 Id
: constant Entity_Id
:= Defining_Identifier
(N
);
1240 Generate_Definition
(Id
);
1241 Set_Is_Pure
(Id
, PF
);
1242 Init_Size_Align
(Id
);
1244 if (Ekind
(Current_Scope
) /= E_Package
1245 and then Ekind
(Current_Scope
) /= E_Generic_Package
)
1246 or else In_Private_Part
(Current_Scope
)
1248 Error_Msg_N
("invalid context for private declaration", N
);
1251 New_Private_Type
(N
, Id
, N
);
1252 Set_Depends_On_Private
(Id
);
1253 end Analyze_Private_Type_Declaration
;
1255 ----------------------------------
1256 -- Check_Anonymous_Access_Types --
1257 ----------------------------------
1259 procedure Check_Anonymous_Access_Types
1260 (Spec_Id
: Entity_Id
;
1267 -- Itype references are only needed by gigi, to force elaboration of
1268 -- itypes. In the absence of code generation, they are not needed.
1270 if not Expander_Active
then
1274 E
:= First_Entity
(Spec_Id
);
1275 while Present
(E
) loop
1276 if Ekind
(E
) = E_Anonymous_Access_Type
1277 and then From_With_Type
(E
)
1279 IR
:= Make_Itype_Reference
(Sloc
(P_Body
));
1282 if No
(Declarations
(P_Body
)) then
1283 Set_Declarations
(P_Body
, New_List
);
1286 Insert_Before
(First
(Declarations
(P_Body
)), IR
);
1291 end Check_Anonymous_Access_Types
;
1293 -------------------------------------------
1294 -- Declare_Inherited_Private_Subprograms --
1295 -------------------------------------------
1297 procedure Declare_Inherited_Private_Subprograms
(Id
: Entity_Id
) is
1301 Op_Elmt_2
: Elmt_Id
;
1302 Prim_Op
: Entity_Id
;
1303 New_Op
: Entity_Id
:= Empty
;
1304 Parent_Subp
: Entity_Id
;
1305 Found_Explicit
: Boolean;
1306 Decl_Privates
: Boolean;
1308 function Is_Primitive_Of
(T
: Entity_Id
; S
: Entity_Id
) return Boolean;
1309 -- Check whether an inherited subprogram is an operation of an
1310 -- untagged derived type.
1312 ---------------------
1313 -- Is_Primitive_Of --
1314 ---------------------
1316 function Is_Primitive_Of
(T
: Entity_Id
; S
: Entity_Id
) return Boolean is
1320 if Etype
(S
) = T
then
1324 Formal
:= First_Formal
(S
);
1325 while Present
(Formal
) loop
1326 if Etype
(Formal
) = T
then
1330 Next_Formal
(Formal
);
1335 end Is_Primitive_Of
;
1337 -- Start of processing for Declare_Inherited_Private_Subprograms
1340 E
:= First_Entity
(Id
);
1341 while Present
(E
) loop
1343 -- If the entity is a nonprivate type extension whose parent
1344 -- type is declared in an open scope, then the type may have
1345 -- inherited operations that now need to be made visible.
1346 -- Ditto if the entity is a formal derived type in a child unit.
1348 if ((Is_Derived_Type
(E
) and then not Is_Private_Type
(E
))
1350 (Nkind
(Parent
(E
)) = N_Private_Extension_Declaration
1351 and then Is_Generic_Type
(E
)))
1352 and then In_Open_Scopes
(Scope
(Etype
(E
)))
1353 and then E
= Base_Type
(E
)
1355 if Is_Tagged_Type
(E
) then
1356 Op_List
:= Primitive_Operations
(E
);
1358 Decl_Privates
:= False;
1360 Op_Elmt
:= First_Elmt
(Op_List
);
1361 while Present
(Op_Elmt
) loop
1362 Prim_Op
:= Node
(Op_Elmt
);
1364 -- If the primitive operation is an implicit operation
1365 -- with an internal name whose parent operation has
1366 -- a normal name, then we now need to either declare the
1367 -- operation (i.e., make it visible), or replace it
1368 -- by an overriding operation if one exists.
1370 if Present
(Alias
(Prim_Op
))
1371 and then Find_Dispatching_Type
(Alias
(Prim_Op
)) /= E
1372 and then not Comes_From_Source
(Prim_Op
)
1373 and then Is_Internal_Name
(Chars
(Prim_Op
))
1374 and then not Is_Internal_Name
(Chars
(Alias
(Prim_Op
)))
1376 Parent_Subp
:= Alias
(Prim_Op
);
1378 Found_Explicit
:= False;
1379 Op_Elmt_2
:= Next_Elmt
(Op_Elmt
);
1380 while Present
(Op_Elmt_2
) loop
1381 if Chars
(Node
(Op_Elmt_2
)) = Chars
(Parent_Subp
)
1382 and then Type_Conformant
(Prim_Op
, Node
(Op_Elmt_2
))
1384 -- The private inherited operation has been
1385 -- overridden by an explicit subprogram, so
1386 -- change the private op's list element to
1387 -- designate the explicit so the explicit
1388 -- one will get the right dispatching slot.
1390 New_Op
:= Node
(Op_Elmt_2
);
1391 Replace_Elmt
(Op_Elmt
, New_Op
);
1392 Remove_Elmt
(Op_List
, Op_Elmt_2
);
1393 Found_Explicit
:= True;
1394 Set_Is_Overriding_Operation
(New_Op
);
1395 Decl_Privates
:= True;
1400 Next_Elmt
(Op_Elmt_2
);
1403 if not Found_Explicit
then
1405 (New_Op
, Alias
(Prim_Op
), E
, Etype
(E
));
1408 (Is_Dispatching_Operation
(New_Op
)
1409 and then Node
(Last_Elmt
(Op_List
)) = New_Op
);
1411 -- Substitute the new operation for the old one
1412 -- in the type's primitive operations list. Since
1413 -- the new operation was also just added to the end
1414 -- of list, the last element must be removed.
1416 -- (Question: is there a simpler way of declaring
1417 -- the operation, say by just replacing the name
1418 -- of the earlier operation, reentering it in the
1419 -- in the symbol table (how?), and marking it as
1422 Replace_Elmt
(Op_Elmt
, New_Op
);
1423 Remove_Last_Elmt
(Op_List
);
1424 Decl_Privates
:= True;
1428 Next_Elmt
(Op_Elmt
);
1431 -- The type's DT attributes need to be recalculated
1432 -- in the case where private dispatching operations
1433 -- have been added or overridden. Normally this action
1434 -- occurs during type freezing, but we force it here
1435 -- since the type may already have been frozen (e.g.,
1436 -- if the type's package has an empty private part).
1437 -- This can only be done if expansion is active, otherwise
1438 -- Tag may not be present.
1441 and then Expander_Active
1443 Set_All_DT_Position
(E
);
1447 -- Non-tagged type, scan forward to locate
1448 -- inherited hidden operations.
1450 Prim_Op
:= Next_Entity
(E
);
1451 while Present
(Prim_Op
) loop
1452 if Is_Subprogram
(Prim_Op
)
1453 and then Present
(Alias
(Prim_Op
))
1454 and then not Comes_From_Source
(Prim_Op
)
1455 and then Is_Internal_Name
(Chars
(Prim_Op
))
1456 and then not Is_Internal_Name
(Chars
(Alias
(Prim_Op
)))
1457 and then Is_Primitive_Of
(E
, Prim_Op
)
1459 Derive_Subprogram
(New_Op
, Alias
(Prim_Op
), E
, Etype
(E
));
1462 Next_Entity
(Prim_Op
);
1469 end Declare_Inherited_Private_Subprograms
;
1471 -----------------------
1472 -- End_Package_Scope --
1473 -----------------------
1475 procedure End_Package_Scope
(P
: Entity_Id
) is
1477 Uninstall_Declarations
(P
);
1479 end End_Package_Scope
;
1481 ---------------------------
1482 -- Exchange_Declarations --
1483 ---------------------------
1485 procedure Exchange_Declarations
(Id
: Entity_Id
) is
1486 Full_Id
: constant Entity_Id
:= Full_View
(Id
);
1487 H1
: constant Entity_Id
:= Homonym
(Id
);
1488 Next1
: constant Entity_Id
:= Next_Entity
(Id
);
1493 -- If missing full declaration for type, nothing to exchange
1495 if No
(Full_Id
) then
1499 -- Otherwise complete the exchange, and preserve semantic links
1501 Next2
:= Next_Entity
(Full_Id
);
1502 H2
:= Homonym
(Full_Id
);
1504 -- Reset full declaration pointer to reflect the switched entities
1505 -- and readjust the next entity chains.
1507 Exchange_Entities
(Id
, Full_Id
);
1509 Set_Next_Entity
(Id
, Next1
);
1510 Set_Homonym
(Id
, H1
);
1512 Set_Full_View
(Full_Id
, Id
);
1513 Set_Next_Entity
(Full_Id
, Next2
);
1514 Set_Homonym
(Full_Id
, H2
);
1515 end Exchange_Declarations
;
1517 ----------------------------
1518 -- Install_Package_Entity --
1519 ----------------------------
1521 procedure Install_Package_Entity
(Id
: Entity_Id
) is
1523 if not Is_Internal
(Id
) then
1524 if Debug_Flag_E
then
1525 Write_Str
("Install: ");
1526 Write_Name
(Chars
(Id
));
1530 if not Is_Child_Unit
(Id
) then
1531 Set_Is_Immediately_Visible
(Id
);
1535 end Install_Package_Entity
;
1537 ----------------------------------
1538 -- Install_Private_Declarations --
1539 ----------------------------------
1541 procedure Install_Private_Declarations
(P
: Entity_Id
) is
1543 Priv_Elmt
: Elmt_Id
;
1548 -- First exchange declarations for private types, so that the
1549 -- full declaration is visible. For each private type, we check
1550 -- its Private_Dependents list and also exchange any subtypes of
1551 -- or derived types from it. Finally, if this is a Taft amendment
1552 -- type, the incomplete declaration is irrelevant, and we want to
1553 -- link the eventual full declaration with the original private
1554 -- one so we also skip the exchange.
1556 Id
:= First_Entity
(P
);
1557 while Present
(Id
) and then Id
/= First_Private_Entity
(P
) loop
1558 if Is_Private_Base_Type
(Id
)
1559 and then Comes_From_Source
(Full_View
(Id
))
1560 and then Present
(Full_View
(Id
))
1561 and then Scope
(Full_View
(Id
)) = Scope
(Id
)
1562 and then Ekind
(Full_View
(Id
)) /= E_Incomplete_Type
1564 -- If there is a use-type clause on the private type, set the
1565 -- full view accordingly.
1567 Set_In_Use
(Full_View
(Id
), In_Use
(Id
));
1568 Full
:= Full_View
(Id
);
1570 if Is_Private_Base_Type
(Full
)
1571 and then Has_Private_Declaration
(Full
)
1572 and then Nkind
(Parent
(Full
)) = N_Full_Type_Declaration
1573 and then In_Open_Scopes
(Scope
(Etype
(Full
)))
1574 and then In_Package_Body
(Current_Scope
)
1575 and then not Is_Private_Type
(Etype
(Full
))
1577 -- This is the completion of a private type by a derivation
1578 -- from another private type which is not private anymore. This
1579 -- can only happen in a package nested within a child package,
1580 -- when the parent type is defined in the parent unit. At this
1581 -- point the current type is not private either, and we have to
1582 -- install the underlying full view, which is now visible.
1584 if No
(Full_View
(Full
))
1585 and then Present
(Underlying_Full_View
(Full
))
1587 Set_Full_View
(Id
, Underlying_Full_View
(Full
));
1588 Set_Underlying_Full_View
(Full
, Empty
);
1589 Set_Is_Frozen
(Full_View
(Id
));
1593 Priv_Elmt
:= First_Elmt
(Private_Dependents
(Id
));
1595 Exchange_Declarations
(Id
);
1596 Set_Is_Immediately_Visible
(Id
);
1598 while Present
(Priv_Elmt
) loop
1599 Priv
:= Node
(Priv_Elmt
);
1601 -- Before the exchange, verify that the presence of the
1602 -- Full_View field. It will be empty if the entity
1603 -- has already been installed due to a previous call.
1605 if Present
(Full_View
(Priv
))
1606 and then Is_Visible_Dependent
(Priv
)
1609 -- For each subtype that is swapped, we also swap the
1610 -- reference to it in Private_Dependents, to allow access
1611 -- to it when we swap them out in End_Package_Scope.
1613 Replace_Elmt
(Priv_Elmt
, Full_View
(Priv
));
1614 Exchange_Declarations
(Priv
);
1615 Set_Is_Immediately_Visible
1616 (Priv
, In_Open_Scopes
(Scope
(Priv
)));
1617 Set_Is_Potentially_Use_Visible
1618 (Priv
, Is_Potentially_Use_Visible
(Node
(Priv_Elmt
)));
1621 Next_Elmt
(Priv_Elmt
);
1628 -- Next make other declarations in the private part visible as well
1630 Id
:= First_Private_Entity
(P
);
1631 while Present
(Id
) loop
1632 Install_Package_Entity
(Id
);
1633 Set_Is_Hidden
(Id
, False);
1637 -- Indicate that the private part is currently visible, so it can be
1638 -- properly reset on exit.
1640 Set_In_Private_Part
(P
);
1641 end Install_Private_Declarations
;
1643 ----------------------------------
1644 -- Install_Visible_Declarations --
1645 ----------------------------------
1647 procedure Install_Visible_Declarations
(P
: Entity_Id
) is
1649 Last_Entity
: Entity_Id
;
1653 (Is_Package_Or_Generic_Package
(P
) or else Is_Record_Type
(P
));
1655 if Is_Package_Or_Generic_Package
(P
) then
1656 Last_Entity
:= First_Private_Entity
(P
);
1658 Last_Entity
:= Empty
;
1661 Id
:= First_Entity
(P
);
1662 while Present
(Id
) and then Id
/= Last_Entity
loop
1663 Install_Package_Entity
(Id
);
1666 end Install_Visible_Declarations
;
1668 --------------------------
1669 -- Is_Private_Base_Type --
1670 --------------------------
1672 function Is_Private_Base_Type
(E
: Entity_Id
) return Boolean is
1674 return Ekind
(E
) = E_Private_Type
1675 or else Ekind
(E
) = E_Limited_Private_Type
1676 or else Ekind
(E
) = E_Record_Type_With_Private
;
1677 end Is_Private_Base_Type
;
1679 --------------------------
1680 -- Is_Visible_Dependent --
1681 --------------------------
1683 function Is_Visible_Dependent
(Dep
: Entity_Id
) return Boolean
1685 S
: constant Entity_Id
:= Scope
(Dep
);
1688 -- Renamings created for actual types have the visibility of the
1691 if Ekind
(S
) = E_Package
1692 and then Is_Generic_Instance
(S
)
1693 and then (Is_Generic_Actual_Type
(Dep
)
1694 or else Is_Generic_Actual_Type
(Full_View
(Dep
)))
1698 elsif not (Is_Derived_Type
(Dep
))
1699 and then Is_Derived_Type
(Full_View
(Dep
))
1701 -- When instantiating a package body, the scope stack is empty,
1702 -- so check instead whether the dependent type is defined in
1703 -- the same scope as the instance itself.
1705 return In_Open_Scopes
(S
)
1706 or else (Is_Generic_Instance
(Current_Scope
)
1707 and then Scope
(Dep
) = Scope
(Current_Scope
));
1711 end Is_Visible_Dependent
;
1713 ----------------------------
1714 -- May_Need_Implicit_Body --
1715 ----------------------------
1717 procedure May_Need_Implicit_Body
(E
: Entity_Id
) is
1718 P
: constant Node_Id
:= Unit_Declaration_Node
(E
);
1719 S
: constant Node_Id
:= Parent
(P
);
1724 if not Has_Completion
(E
)
1725 and then Nkind
(P
) = N_Package_Declaration
1726 and then Present
(Activation_Chain_Entity
(P
))
1729 Make_Package_Body
(Sloc
(E
),
1730 Defining_Unit_Name
=> Make_Defining_Identifier
(Sloc
(E
),
1731 Chars
=> Chars
(E
)),
1732 Declarations
=> New_List
);
1734 if Nkind
(S
) = N_Package_Specification
then
1735 if Present
(Private_Declarations
(S
)) then
1736 Decls
:= Private_Declarations
(S
);
1738 Decls
:= Visible_Declarations
(S
);
1741 Decls
:= Declarations
(S
);
1747 end May_Need_Implicit_Body
;
1749 ----------------------
1750 -- New_Private_Type --
1751 ----------------------
1753 procedure New_Private_Type
(N
: Node_Id
; Id
: Entity_Id
; Def
: Node_Id
) is
1757 if Limited_Present
(Def
) then
1758 Set_Ekind
(Id
, E_Limited_Private_Type
);
1760 Set_Ekind
(Id
, E_Private_Type
);
1764 Set_Has_Delayed_Freeze
(Id
);
1765 Set_Is_First_Subtype
(Id
);
1766 Init_Size_Align
(Id
);
1768 Set_Is_Constrained
(Id
,
1769 No
(Discriminant_Specifications
(N
))
1770 and then not Unknown_Discriminants_Present
(N
));
1772 -- Set tagged flag before processing discriminants, to catch
1775 Set_Is_Tagged_Type
(Id
, Tagged_Present
(Def
));
1777 Set_Discriminant_Constraint
(Id
, No_Elist
);
1778 Set_Stored_Constraint
(Id
, No_Elist
);
1780 if Present
(Discriminant_Specifications
(N
)) then
1782 Process_Discriminants
(N
);
1785 elsif Unknown_Discriminants_Present
(N
) then
1786 Set_Has_Unknown_Discriminants
(Id
);
1789 Set_Private_Dependents
(Id
, New_Elmt_List
);
1791 if Tagged_Present
(Def
) then
1792 Set_Ekind
(Id
, E_Record_Type_With_Private
);
1793 Make_Class_Wide_Type
(Id
);
1794 Set_Primitive_Operations
(Id
, New_Elmt_List
);
1795 Set_Is_Abstract
(Id
, Abstract_Present
(Def
));
1796 Set_Is_Limited_Record
(Id
, Limited_Present
(Def
));
1797 Set_Has_Delayed_Freeze
(Id
, True);
1799 elsif Abstract_Present
(Def
) then
1800 Error_Msg_N
("only a tagged type can be abstract", N
);
1802 end New_Private_Type
;
1804 ----------------------------
1805 -- Uninstall_Declarations --
1806 ----------------------------
1808 procedure Uninstall_Declarations
(P
: Entity_Id
) is
1809 Decl
: constant Node_Id
:= Unit_Declaration_Node
(P
);
1812 Priv_Elmt
: Elmt_Id
;
1813 Priv_Sub
: Entity_Id
;
1815 procedure Preserve_Full_Attributes
(Priv
, Full
: Entity_Id
);
1816 -- Copy to the private declaration the attributes of the full view
1817 -- that need to be available for the partial view also.
1819 function Type_In_Use
(T
: Entity_Id
) return Boolean;
1820 -- Check whether type or base type appear in an active use_type clause
1822 ------------------------------
1823 -- Preserve_Full_Attributes --
1824 ------------------------------
1826 procedure Preserve_Full_Attributes
(Priv
, Full
: Entity_Id
) is
1827 Priv_Is_Base_Type
: constant Boolean := Priv
= Base_Type
(Priv
);
1830 Set_Size_Info
(Priv
, (Full
));
1831 Set_RM_Size
(Priv
, RM_Size
(Full
));
1832 Set_Size_Known_At_Compile_Time
(Priv
, Size_Known_At_Compile_Time
1834 Set_Is_Volatile
(Priv
, Is_Volatile
(Full
));
1835 Set_Treat_As_Volatile
(Priv
, Treat_As_Volatile
(Full
));
1836 Set_Is_Ada_2005_Only
(Priv
, Is_Ada_2005_Only
(Full
));
1838 if Is_Unchecked_Union
(Full
) then
1839 Set_Is_Unchecked_Union
(Base_Type
(Priv
));
1841 -- Why is atomic not copied here ???
1843 if Referenced
(Full
) then
1844 Set_Referenced
(Priv
);
1847 if Priv_Is_Base_Type
then
1848 Set_Is_Controlled
(Priv
, Is_Controlled
(Base_Type
(Full
)));
1849 Set_Finalize_Storage_Only
(Priv
, Finalize_Storage_Only
1850 (Base_Type
(Full
)));
1851 Set_Has_Task
(Priv
, Has_Task
(Base_Type
(Full
)));
1852 Set_Has_Controlled_Component
(Priv
, Has_Controlled_Component
1853 (Base_Type
(Full
)));
1856 Set_Freeze_Node
(Priv
, Freeze_Node
(Full
));
1858 if Is_Tagged_Type
(Priv
)
1859 and then Is_Tagged_Type
(Full
)
1860 and then not Error_Posted
(Full
)
1862 if Priv_Is_Base_Type
then
1864 -- Ada 2005 (AI-345): The full view of a type implementing
1865 -- an interface can be a task type.
1867 -- type T is new I with private;
1869 -- task type T is new I with ...
1871 if Is_Interface
(Etype
(Priv
))
1872 and then Is_Concurrent_Type
(Base_Type
(Full
))
1874 -- Protect the frontend against previous errors
1876 if Present
(Corresponding_Record_Type
1879 Set_Access_Disp_Table
1880 (Priv
, Access_Disp_Table
1881 (Corresponding_Record_Type
(Base_Type
(Full
))));
1883 -- Generic context, or previous errors
1890 Set_Access_Disp_Table
1891 (Priv
, Access_Disp_Table
(Base_Type
(Full
)));
1895 Set_First_Entity
(Priv
, First_Entity
(Full
));
1896 Set_Last_Entity
(Priv
, Last_Entity
(Full
));
1897 Set_Has_Discriminants
(Priv
, Has_Discriminants
(Full
));
1899 end Preserve_Full_Attributes
;
1905 function Type_In_Use
(T
: Entity_Id
) return Boolean is
1907 return Scope
(Base_Type
(T
)) = P
1908 and then (In_Use
(T
) or else In_Use
(Base_Type
(T
)));
1911 -- Start of processing for Uninstall_Declarations
1914 Id
:= First_Entity
(P
);
1915 while Present
(Id
) and then Id
/= First_Private_Entity
(P
) loop
1916 if Debug_Flag_E
then
1917 Write_Str
("unlinking visible entity ");
1918 Write_Int
(Int
(Id
));
1922 -- On exit from the package scope, we must preserve the visibility
1923 -- established by use clauses in the current scope. Two cases:
1925 -- a) If the entity is an operator, it may be a primitive operator of
1926 -- a type for which there is a visible use-type clause.
1928 -- b) for other entities, their use-visibility is determined by a
1929 -- visible use clause for the package itself. For a generic instance,
1930 -- the instantiation of the formals appears in the visible part,
1931 -- but the formals are private and remain so.
1933 if Ekind
(Id
) = E_Function
1934 and then Is_Operator_Symbol_Name
(Chars
(Id
))
1935 and then not Is_Hidden
(Id
)
1936 and then not Error_Posted
(Id
)
1938 Set_Is_Potentially_Use_Visible
(Id
,
1940 or else Type_In_Use
(Etype
(Id
))
1941 or else Type_In_Use
(Etype
(First_Formal
(Id
)))
1942 or else (Present
(Next_Formal
(First_Formal
(Id
)))
1945 (Etype
(Next_Formal
(First_Formal
(Id
))))));
1947 Set_Is_Potentially_Use_Visible
(Id
,
1948 In_Use
(P
) and not Is_Hidden
(Id
));
1951 -- Local entities are not immediately visible outside of the package
1953 Set_Is_Immediately_Visible
(Id
, False);
1955 -- If this is a private type with a full view (for example a local
1956 -- subtype of a private type declared elsewhere), ensure that the
1957 -- full view is also removed from visibility: it may be exposed when
1958 -- swapping views in an instantiation.
1961 and then Present
(Full_View
(Id
))
1963 Set_Is_Immediately_Visible
(Full_View
(Id
), False);
1966 if Is_Tagged_Type
(Id
) and then Ekind
(Id
) = E_Record_Type
then
1967 Check_Abstract_Overriding
(Id
);
1968 Check_Conventions
(Id
);
1971 if (Ekind
(Id
) = E_Private_Type
1972 or else Ekind
(Id
) = E_Limited_Private_Type
)
1973 and then No
(Full_View
(Id
))
1974 and then not Is_Generic_Type
(Id
)
1975 and then not Is_Derived_Type
(Id
)
1977 Error_Msg_N
("missing full declaration for private type&", Id
);
1979 elsif Ekind
(Id
) = E_Record_Type_With_Private
1980 and then not Is_Generic_Type
(Id
)
1981 and then No
(Full_View
(Id
))
1983 if Nkind
(Parent
(Id
)) = N_Private_Type_Declaration
then
1984 Error_Msg_N
("missing full declaration for private type&", Id
);
1987 ("missing full declaration for private extension", Id
);
1990 elsif Ekind
(Id
) = E_Constant
1991 and then No
(Constant_Value
(Id
))
1992 and then No
(Full_View
(Id
))
1993 and then not Is_Imported
(Id
)
1994 and then (Nkind
(Parent
(Id
)) /= N_Object_Declaration
1995 or else not No_Initialization
(Parent
(Id
)))
1997 if not Has_Private_Declaration
(Etype
(Id
)) then
1999 -- We assume that the user did not not intend a deferred
2000 -- constant declaration, and the expression is just missing.
2003 ("constant declaration requires initialization expression",
2006 if Is_Limited_Type
(Etype
(Id
)) then
2008 ("\if variable intended, remove CONSTANT from declaration",
2014 ("missing full declaration for deferred constant ('R'M 7.4)",
2017 if Is_Limited_Type
(Etype
(Id
)) then
2019 ("\if variable intended, remove CONSTANT from declaration",
2028 -- If the specification was installed as the parent of a public child
2029 -- unit, the private declarations were not installed, and there is
2032 if not In_Private_Part
(P
) then
2035 Set_In_Private_Part
(P
, False);
2038 -- Make private entities invisible and exchange full and private
2039 -- declarations for private types.
2041 while Present
(Id
) loop
2042 if Debug_Flag_E
then
2043 Write_Str
("unlinking private entity ");
2044 Write_Int
(Int
(Id
));
2048 if Is_Tagged_Type
(Id
) and then Ekind
(Id
) = E_Record_Type
then
2049 Check_Abstract_Overriding
(Id
);
2050 Check_Conventions
(Id
);
2053 Set_Is_Immediately_Visible
(Id
, False);
2055 if Is_Private_Base_Type
(Id
)
2056 and then Present
(Full_View
(Id
))
2058 Full
:= Full_View
(Id
);
2060 -- If the partial view is not declared in the visible part
2061 -- of the package (as is the case when it is a type derived
2062 -- from some other private type in the private part of the
2063 -- current package), no exchange takes place.
2066 or else List_Containing
(Parent
(Id
))
2067 /= Visible_Declarations
(Specification
(Decl
))
2072 -- The entry in the private part points to the full declaration,
2073 -- which is currently visible. Exchange them so only the private
2074 -- type declaration remains accessible, and link private and
2075 -- full declaration in the opposite direction. Before the actual
2076 -- exchange, we copy back attributes of the full view that
2077 -- must be available to the partial view too.
2079 Preserve_Full_Attributes
(Id
, Full
);
2081 Set_Is_Potentially_Use_Visible
(Id
, In_Use
(P
));
2083 if Is_Indefinite_Subtype
(Full
)
2084 and then not Is_Indefinite_Subtype
(Id
)
2087 ("full view of type must be definite subtype", Full
);
2090 Priv_Elmt
:= First_Elmt
(Private_Dependents
(Id
));
2092 -- Swap out the subtypes and derived types of Id that were
2093 -- compiled in this scope, or installed previously by
2094 -- Install_Private_Declarations.
2095 -- Before we do the swap, we verify the presence of the
2096 -- Full_View field which may be empty due to a swap by
2097 -- a previous call to End_Package_Scope (e.g. from the
2098 -- freezing mechanism).
2100 while Present
(Priv_Elmt
) loop
2101 Priv_Sub
:= Node
(Priv_Elmt
);
2103 if Present
(Full_View
(Priv_Sub
)) then
2105 if Scope
(Priv_Sub
) = P
2106 or else not In_Open_Scopes
(Scope
(Priv_Sub
))
2108 Set_Is_Immediately_Visible
(Priv_Sub
, False);
2111 if Is_Visible_Dependent
(Priv_Sub
) then
2112 Preserve_Full_Attributes
2113 (Priv_Sub
, Full_View
(Priv_Sub
));
2114 Replace_Elmt
(Priv_Elmt
, Full_View
(Priv_Sub
));
2115 Exchange_Declarations
(Priv_Sub
);
2119 Next_Elmt
(Priv_Elmt
);
2122 -- Now restore the type itself to its private view
2124 Exchange_Declarations
(Id
);
2126 elsif Ekind
(Id
) = E_Incomplete_Type
2127 and then No
(Full_View
(Id
))
2129 -- Mark Taft amendment types
2131 Set_Has_Completion_In_Body
(Id
);
2133 elsif not Is_Child_Unit
(Id
)
2134 and then (not Is_Private_Type
(Id
)
2135 or else No
(Full_View
(Id
)))
2138 Set_Is_Potentially_Use_Visible
(Id
, False);
2144 end Uninstall_Declarations
;
2146 ------------------------
2147 -- Unit_Requires_Body --
2148 ------------------------
2150 function Unit_Requires_Body
(P
: Entity_Id
) return Boolean is
2154 -- Imported entity never requires body. Right now, only
2155 -- subprograms can be imported, but perhaps in the future
2156 -- we will allow import of packages.
2158 if Is_Imported
(P
) then
2161 -- Body required if library package with pragma Elaborate_Body
2163 elsif Has_Pragma_Elaborate_Body
(P
) then
2166 -- Body required if subprogram
2168 elsif Is_Subprogram
(P
) or else Is_Generic_Subprogram
(P
) then
2171 -- Treat a block as requiring a body
2173 elsif Ekind
(P
) = E_Block
then
2176 elsif Ekind
(P
) = E_Package
2177 and then Nkind
(Parent
(P
)) = N_Package_Specification
2178 and then Present
(Generic_Parent
(Parent
(P
)))
2181 G_P
: constant Entity_Id
:= Generic_Parent
(Parent
(P
));
2183 if Has_Pragma_Elaborate_Body
(G_P
) then
2189 -- Otherwise search entity chain for entity requiring completion
2191 E
:= First_Entity
(P
);
2192 while Present
(E
) loop
2194 -- Always ignore child units. Child units get added to the entity
2195 -- list of a parent unit, but are not original entities of the
2196 -- parent, and so do not affect whether the parent needs a body.
2198 if Is_Child_Unit
(E
) then
2201 -- Ignore formal packages and their renamings
2203 elsif Ekind
(E
) = E_Package
2204 and then Nkind
(Original_Node
(Unit_Declaration_Node
(E
))) =
2205 N_Formal_Package_Declaration
2209 -- Otherwise test to see if entity requires a completion
2211 elsif (Is_Overloadable
(E
)
2212 and then Ekind
(E
) /= E_Enumeration_Literal
2213 and then Ekind
(E
) /= E_Operator
2214 and then not Is_Abstract
(E
)
2215 and then not Has_Completion
(E
))
2218 (Ekind
(E
) = E_Package
2220 and then not Has_Completion
(E
)
2221 and then Unit_Requires_Body
(E
))
2224 (Ekind
(E
) = E_Incomplete_Type
and then No
(Full_View
(E
)))
2227 ((Ekind
(E
) = E_Task_Type
or else
2228 Ekind
(E
) = E_Protected_Type
)
2229 and then not Has_Completion
(E
))
2232 (Ekind
(E
) = E_Generic_Package
and then E
/= P
2233 and then not Has_Completion
(E
)
2234 and then Unit_Requires_Body
(E
))
2237 (Is_Generic_Subprogram
(E
)
2238 and then not Has_Completion
(E
))
2243 -- Entity that does not require completion
2253 end Unit_Requires_Body
;