Subversion Repositories scarts

------------------------------------------------------------------------------

--                                                                          --

--                         GNAT COMPILER COMPONENTS                         --

--                                                                          --

--                              S E M . C H 7                               --

--                                                                          --

--                                 B o d y                                  --

--                                                                          --

--          Copyright (C) 1992-2005, Free Software Foundation, Inc.         --

--                                                                          --

-- GNAT is free software;  you can  redistribute it  and/or modify it under --

-- terms of the  GNU General Public License as published  by the Free Soft- --

-- ware  Foundation;  either version 2,  or (at your option) any later ver- --

-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --

-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --

-- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --

-- for  more details.  You should have  received  a copy of the GNU General --

-- Public License  distributed with GNAT;  see file COPYING.  If not, write --

-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --

-- Boston, MA 02110-1301, USA.                                              --

--                                                                          --

-- GNAT was originally developed  by the GNAT team at  New York University. --

-- Extensive contributions were provided by Ada Core Technologies Inc.      --

--                                                                          --

------------------------------------------------------------------------------

--  This package contains the routines to process package specifications and

--  bodies. The most important semantic aspects of package processing are the

--  handling of private and full declarations, and the construction of

--  dispatch tables for tagged types.

with Atree;    use Atree;

with Debug;    use Debug;

with Einfo;    use Einfo;

with Elists;   use Elists;

with Errout;   use Errout;

with Exp_Disp; use Exp_Disp;

with Exp_Dbug; use Exp_Dbug;

with Lib;      use Lib;

with Lib.Xref; use Lib.Xref;

with Namet;    use Namet;

with Nmake;    use Nmake;

with Nlists;   use Nlists;

with Opt;      use Opt;

with Output;   use Output;

with Sem;      use Sem;

with Sem_Cat;  use Sem_Cat;

with Sem_Ch3;  use Sem_Ch3;

with Sem_Ch6;  use Sem_Ch6;

with Sem_Ch8;  use Sem_Ch8;

with Sem_Ch10; use Sem_Ch10;

with Sem_Ch12; use Sem_Ch12;

with Sem_Util; use Sem_Util;

with Sem_Warn; use Sem_Warn;

with Snames;   use Snames;

with Stand;    use Stand;

with Sinfo;    use Sinfo;

with Sinput;   use Sinput;

with Style;

package body Sem_Ch7 is

   -----------------------------------

   -- Handling private declarations --

   -----------------------------------

   --  The principle that each entity has a single defining occurrence clashes

   --  with the presence of two separate definitions for private types: the

   --  first is the private type declaration, and the second is the full type

   --  declaration. It is important that all references to the type point to

   --  the same defining occurrence, namely the first one. To enforce the two

   --  separate views of the entity, the corresponding information is swapped

   --  between the two declarations. Outside of the package, the defining

   --  occurrence only contains the private declaration information, while in

   --  the private part and the body of the package the defining occurrence

   --  contains the full declaration. To simplify the swap, the defining

   --  occurrence that currently holds the private declaration points to the

   --  full declaration. During semantic processing the defining occurrence

   --  also points to a list of private dependents, that is to say access types

   --  or composite types whose designated types or component types are

   --  subtypes or derived types of the private type in question. After the

   --  full declaration has been seen, the private dependents are updated to

   --  indicate that they have full definitions.

   -----------------------

   -- Local Subprograms --

   -----------------------

   procedure Install_Package_Entity (Id : Entity_Id);

   --  Basic procedure for the previous two. Places one entity on its

   --  visibility chain, and recurses on the visible part if the entity

   --  is an inner package.

   function Is_Private_Base_Type (E : Entity_Id) return Boolean;

   --  True for a private type that is not a subtype

   function Is_Visible_Dependent (Dep : Entity_Id) return Boolean;

   --  If the private dependent is a private type whose full view is

   --  derived from the parent type, its full properties are revealed

   --  only if we are in the immediate scope of the private dependent.

   --  Should this predicate be tightened further???

   procedure Declare_Inherited_Private_Subprograms (Id : Entity_Id);

   --  Called upon entering the private part of a public child package

   --  and the body of a nested package, to potentially declare certain

   --  inherited subprograms that were inherited by types in the visible

   --  part, but whose declaration was deferred because the parent

   --  operation was private and not visible at that point. These

   --  subprograms are located by traversing the visible part declarations

   --  looking for non-private type extensions and then examining each of

   --  the primitive operations of such types to find those that were

   --  inherited but declared with a special internal name. Each such

   --  operation is now declared as an operation with a normal name (using

   --  the name of the parent operation) and replaces the previous implicit

   --  operation in the primitive operations list of the type. If the

   --  inherited private operation has been overridden, then it's

   --  replaced by the overriding operation.

   --------------------------

   -- Analyze_Package_Body --

   --------------------------

   procedure Analyze_Package_Body (N : Node_Id) is

      Loc              : constant Source_Ptr := Sloc (N);

      HSS              : Node_Id;

      Body_Id          : Entity_Id;

      Spec_Id          : Entity_Id;

      Last_Spec_Entity : Entity_Id;

      New_N            : Node_Id;

      Pack_Decl        : Node_Id;

      procedure Install_Composite_Operations (P : Entity_Id);

      --  Composite types declared in the current scope may depend on

      --  types that were private at the point of declaration, and whose

      --  full view is now in  scope. Indicate that the corresponding

      --  operations on the composite type are available.

      ----------------------------------

      -- Install_Composite_Operations --

      ----------------------------------

      procedure Install_Composite_Operations (P : Entity_Id) is

         Id : Entity_Id;

      begin

         Id := First_Entity (P);

         while Present (Id) loop

            if Is_Type (Id)

              and then (Is_Limited_Composite (Id)

                         or else Is_Private_Composite (Id))

              and then No (Private_Component (Id))

            then

               Set_Is_Limited_Composite (Id, False);

               Set_Is_Private_Composite (Id, False);

            end if;

            Next_Entity (Id);

         end loop;

      end Install_Composite_Operations;

   --  Start of processing for Analyze_Package_Body

   begin

      --  Find corresponding package specification, and establish the

      --  current scope. The visible defining entity for the package is the

      --  defining occurrence in the spec. On exit from the package body, all

      --  body declarations are attached to the defining entity for the body,

      --  but the later is never used for name resolution. In this fashion

      --  there is only one visible entity that denotes the package.

      if Debug_Flag_C then

         Write_Str ("====  Compiling package body ");

         Write_Name (Chars (Defining_Entity (N)));

         Write_Str (" from ");

         Write_Location (Loc);

         Write_Eol;

      end if;

      --  Set Body_Id. Note that this Will be reset to point to the

      --  generic copy later on in the generic case.

      Body_Id := Defining_Entity (N);

      if Present (Corresponding_Spec (N)) then

         --  Body is body of package instantiation. Corresponding spec

         --  has already been set.

         Spec_Id := Corresponding_Spec (N);

         Pack_Decl := Unit_Declaration_Node (Spec_Id);

      else

         Spec_Id := Current_Entity_In_Scope (Defining_Entity (N));

         if Present (Spec_Id)

           and then Is_Package_Or_Generic_Package (Spec_Id)

         then

            Pack_Decl := Unit_Declaration_Node (Spec_Id);

            if Nkind (Pack_Decl) = N_Package_Renaming_Declaration then

               Error_Msg_N ("cannot supply body for package renaming", N);

               return;

            elsif Present (Corresponding_Body (Pack_Decl)) then

               Error_Msg_N ("redefinition of package body", N);

               return;

            end if;

         else

            Error_Msg_N ("missing specification for package body", N);

            return;

         end if;

         if Is_Package_Or_Generic_Package (Spec_Id)

           and then

             (Scope (Spec_Id) = Standard_Standard

               or else Is_Child_Unit (Spec_Id))

           and then not Unit_Requires_Body (Spec_Id)

         then

            if Ada_Version = Ada_83 then

               Error_Msg_N

                 ("optional package body (not allowed in Ada 95)?", N);

            else

               Error_Msg_N

                 ("spec of this package does not allow a body", N);

            end if;

         end if;

      end if;

      Set_Is_Compilation_Unit (Body_Id, Is_Compilation_Unit (Spec_Id));

      Style.Check_Identifier (Body_Id, Spec_Id);

      if Is_Child_Unit (Spec_Id) then

         if Nkind (Parent (N)) /= N_Compilation_Unit then

            Error_Msg_NE

              ("body of child unit& cannot be an inner package", N, Spec_Id);

         end if;

         Set_Is_Child_Unit (Body_Id);

      end if;

      --  Generic package case

      if Ekind (Spec_Id) = E_Generic_Package then

         --  Disable expansion and perform semantic analysis on copy.

         --  The unannotated body will be used in all instantiations.

         Body_Id := Defining_Entity (N);

         Set_Ekind (Body_Id, E_Package_Body);

         Set_Scope (Body_Id, Scope (Spec_Id));

         Set_Body_Entity (Spec_Id, Body_Id);

         Set_Spec_Entity (Body_Id, Spec_Id);

         New_N := Copy_Generic_Node (N, Empty, Instantiating => False);

         Rewrite (N, New_N);

         --  Update Body_Id to point to the copied node for the remainder

         --  of the processing.

         Body_Id := Defining_Entity (N);

         Start_Generic;

      end if;

      --  The Body_Id is that of the copied node in the generic case, the

      --  current node otherwise. Note that N was rewritten above, so we

      --  must be sure to get the latest Body_Id value.

      Set_Ekind (Body_Id, E_Package_Body);

      Set_Body_Entity (Spec_Id, Body_Id);

      Set_Spec_Entity (Body_Id, Spec_Id);

      --  Defining name for the package body is not a visible entity: Only

      --  the defining name for the declaration is visible.

      Set_Etype (Body_Id, Standard_Void_Type);

      Set_Scope (Body_Id, Scope (Spec_Id));

      Set_Corresponding_Spec (N, Spec_Id);

      Set_Corresponding_Body (Pack_Decl, Body_Id);

      --  The body entity is not used for semantics or code generation, but

      --  it is attached to the entity list of the enclosing scope to simplify

      --  the listing of back-annotations for the types it main contain.

      if Scope (Spec_Id) /= Standard_Standard then

         Append_Entity (Body_Id, Scope (Spec_Id));

      end if;

      --  Indicate that we are currently compiling the body of the package

      Set_In_Package_Body (Spec_Id);

      Set_Has_Completion (Spec_Id);

      Last_Spec_Entity := Last_Entity (Spec_Id);

      New_Scope (Spec_Id);

      Set_Categorization_From_Pragmas (N);

      Install_Visible_Declarations (Spec_Id);

      Install_Private_Declarations (Spec_Id);

      Install_Private_With_Clauses (Spec_Id);

      Install_Composite_Operations (Spec_Id);

      if Ekind (Spec_Id) = E_Generic_Package then

         Set_Use (Generic_Formal_Declarations (Pack_Decl));

      end if;

      Set_Use (Visible_Declarations (Specification (Pack_Decl)));

      Set_Use (Private_Declarations (Specification (Pack_Decl)));

      --  This is a nested package, so it may be necessary to declare

      --  certain inherited subprograms that are not yet visible because

      --  the parent type's subprograms are now visible.

      if Ekind (Scope (Spec_Id)) = E_Package

        and then Scope (Spec_Id) /= Standard_Standard

      then

         Declare_Inherited_Private_Subprograms (Spec_Id);

      end if;

      if Present (Declarations (N)) then

         Analyze_Declarations (Declarations (N));

      end if;

      HSS := Handled_Statement_Sequence (N);

      if Present (HSS) then

         Process_End_Label (HSS, 't', Spec_Id);

         Analyze (HSS);

         --  Check that elaboration code in a preelaborable package body is

         --  empty other than null statements and labels (RM 10.2.1(6)).

         Validate_Null_Statement_Sequence (N);

      end if;

      Validate_Categorization_Dependency (N, Spec_Id);

      Check_Completion (Body_Id);

      --  Generate start of body reference. Note that we do this fairly late,

      --  because the call will use In_Extended_Main_Source_Unit as a check,

      --  and we want to make sure that Corresponding_Stub links are set

      Generate_Reference (Spec_Id, Body_Id, 'b', Set_Ref => False);

      --  For a generic package, collect global references and mark

      --  them on the original body so that they are not resolved

      --  again at the point of instantiation.

      if Ekind (Spec_Id) /= E_Package then

         Save_Global_References (Original_Node (N));

         End_Generic;

      end if;

      --  The entities of the package body have so far been chained onto

      --  the declaration chain for the spec. That's been fine while we

      --  were in the body, since we wanted them to be visible, but now

      --  that we are leaving the package body, they are no longer visible,

      --  so we remove them from the entity chain of the package spec entity,

      --  and copy them to the entity chain of the package body entity, where

      --  they will never again be visible.

      if Present (Last_Spec_Entity) then

         Set_First_Entity (Body_Id, Next_Entity (Last_Spec_Entity));

         Set_Next_Entity (Last_Spec_Entity, Empty);

         Set_Last_Entity (Body_Id, Last_Entity (Spec_Id));

         Set_Last_Entity (Spec_Id, Last_Spec_Entity);

      else

         Set_First_Entity (Body_Id, First_Entity (Spec_Id));

         Set_Last_Entity  (Body_Id, Last_Entity  (Spec_Id));

         Set_First_Entity (Spec_Id, Empty);

         Set_Last_Entity  (Spec_Id, Empty);

      end if;

      End_Package_Scope (Spec_Id);

      --  All entities declared in body are not visible

      declare

         E : Entity_Id;

      begin

         E := First_Entity (Body_Id);

         while Present (E) loop

            Set_Is_Immediately_Visible (E, False);

            Set_Is_Potentially_Use_Visible (E, False);

            Set_Is_Hidden (E);

            --  Child units may appear on the entity list (for example if

            --  they appear in the context of a subunit) but they are not

            --  body entities.

            if not Is_Child_Unit (E) then

               Set_Is_Package_Body_Entity (E);

            end if;

            Next_Entity (E);

         end loop;

      end;

      Check_References (Body_Id);

      --  For a generic unit, check that the formal parameters are referenced,

      --  and that local variables are used, as for regular packages.

      if Ekind (Spec_Id) = E_Generic_Package then

         Check_References (Spec_Id);

      end if;

      --  The processing so far has made all entities of the package body

      --  public (i.e. externally visible to the linker). This is in general

      --  necessary, since inlined or generic bodies, for which code is

      --  generated in other units, may need to see these entities. The

      --  following loop runs backwards from the end of the entities of the

      --  package body making these entities invisible until we reach a

      --  referencer, i.e. a declaration that could reference a previous

      --  declaration, a generic body or an inlined body, or a stub (which

      --  may contain either of these). This is of course an approximation,

      --  but it is conservative and definitely correct.

      --  We only do this at the outer (library) level non-generic packages.

      --  The reason is simply to cut down on the number of external symbols

      --  generated, so this is simply an optimization of the efficiency

      --  of the compilation process. It has no other effect.

      if (Scope (Spec_Id) = Standard_Standard or else Is_Child_Unit (Spec_Id))

        and then not Is_Generic_Unit (Spec_Id)

        and then Present (Declarations (N))

      then

         Make_Non_Public_Where_Possible : declare

            function Has_Referencer

              (L     : List_Id;

               Outer : Boolean)

               return  Boolean;

            --  Traverse the given list of declarations in reverse order.

            --  Return True as soon as a referencer is reached. Return

            --  False if none is found. The Outer parameter is True for

            --  the outer level call, and False for inner level calls for

            --  nested packages. If Outer is True, then any entities up

            --  to the point of hitting a referencer get their Is_Public

            --  flag cleared, so that the entities will be treated as

            --  static entities in the C sense, and need not have fully

            --  qualified names. For inner levels, we need all names to

            --  be fully qualified to deal with the same name appearing

            --  in parallel packages (right now this is tied to their

            --  being external).

            --------------------

            -- Has_Referencer --

            --------------------

            function Has_Referencer

              (L     : List_Id;

               Outer : Boolean)

               return  Boolean

            is

               D : Node_Id;

               E : Entity_Id;

               K : Node_Kind;

               S : Entity_Id;

            begin

               if No (L) then

                  return False;

               end if;

               D := Last (L);

               while Present (D) loop

                  K := Nkind (D);

                  if K in N_Body_Stub then

                     return True;

                  elsif K = N_Subprogram_Body then

                     if Acts_As_Spec (D) then

                        E := Defining_Entity (D);

                        --  An inlined body acts as a referencer. Note also

                        --  that we never reset Is_Public for an inlined

                        --  subprogram. Gigi requires Is_Public to be set.

                        --  Note that we test Has_Pragma_Inline here rather

                        --  than Is_Inlined. We are compiling this for a

                        --  client, and it is the client who will decide

                        --  if actual inlining should occur, so we need to

                        --  assume that the procedure could be inlined for

                        --  the purpose of accessing global entities.

                        if Has_Pragma_Inline (E) then

                           return True;

                        else

                           Set_Is_Public (E, False);

                        end if;

                     else

                        E := Corresponding_Spec (D);

                        if Present (E)

                          and then (Is_Generic_Unit (E)

                                     or else Has_Pragma_Inline (E)

                                     or else Is_Inlined (E))

                        then

                           return True;

                        end if;

                     end if;

                  --  Processing for package bodies

                  elsif K = N_Package_Body

                    and then Present (Corresponding_Spec (D))

                  then

                     E := Corresponding_Spec (D);

                     --  Generic package body is a referencer. It would

                     --  seem that we only have to consider generics that

                     --  can be exported, i.e. where the corresponding spec

                     --  is the spec of the current package, but because of

                     --  nested instantiations, a fully private generic

                     --  body may export other private body entities.

                     if Is_Generic_Unit (E) then

                        return True;

                     --  For non-generic package body, recurse into body

                     --  unless this is an instance, we ignore instances

                     --  since they cannot have references that affect

                     --  outer entities.

                     elsif not Is_Generic_Instance (E) then

                        if Has_Referencer

                             (Declarations (D), Outer => False)

                        then

                           return True;

                        end if;

                     end if;

                  --  Processing for package specs, recurse into declarations.

                  --  Again we skip this for the case of generic instances.

                  elsif K = N_Package_Declaration then

                     S := Specification (D);

                     if not Is_Generic_Unit (Defining_Entity (S)) then

                        if Has_Referencer

                             (Private_Declarations (S), Outer => False)

                        then

                           return True;

                        elsif Has_Referencer

                               (Visible_Declarations (S), Outer => False)

                        then

                           return True;

                        end if;

                     end if;

                  --  Objects and exceptions need not be public if we have

                  --  not encountered a referencer so far. We only reset

                  --  the flag for outer level entities that are not

                  --  imported/exported, and which have no interface name.

                  elsif K = N_Object_Declaration

                    or else K = N_Exception_Declaration

                    or else K = N_Subprogram_Declaration

                  then

                     E := Defining_Entity (D);

                     if Outer

                       and then not Is_Imported (E)

                       and then not Is_Exported (E)

                       and then No (Interface_Name (E))

                     then

                        Set_Is_Public (E, False);

                     end if;

                  end if;

                  Prev (D);

               end loop;

               return False;

            end Has_Referencer;

         --  Start of processing for Make_Non_Public_Where_Possible

         begin

            declare

               Discard : Boolean;

               pragma Warnings (Off, Discard);

            begin

               Discard := Has_Referencer (Declarations (N), Outer => True);

            end;

         end Make_Non_Public_Where_Possible;

      end if;

      --  If expander is not active, then here is where we turn off the

      --  In_Package_Body flag, otherwise it is turned off at the end of

      --  the corresponding expansion routine. If this is an instance body,

      --  we need to qualify names of local entities, because the body may

      --  have been compiled as a preliminary to another instantiation.

      if not Expander_Active then

         Set_In_Package_Body (Spec_Id, False);

         if Is_Generic_Instance (Spec_Id)

           and then Operating_Mode = Generate_Code

         then

            Qualify_Entity_Names (N);

         end if;

      end if;

   end Analyze_Package_Body;

   ---------------------------------

   -- Analyze_Package_Declaration --

   ---------------------------------

   procedure Analyze_Package_Declaration (N : Node_Id) is

      Id : constant Node_Id := Defining_Entity (N);

      PF : Boolean;

   begin

      --  Ada 2005 (AI-217): Check if the package has been erroneously named

      --  in a limited-with clause of its own context. In this case the error

      --  has been previously notified by Analyze_Context.

      --     limited with Pkg; -- ERROR

      --     package Pkg is ...

      if From_With_Type (Id) then

         return;

      end if;

      Generate_Definition (Id);

      Enter_Name (Id);

      Set_Ekind (Id, E_Package);

      Set_Etype (Id, Standard_Void_Type);

      New_Scope (Id);

      PF := Is_Pure (Enclosing_Lib_Unit_Entity);

      Set_Is_Pure (Id, PF);

      Set_Categorization_From_Pragmas (N);

      if Debug_Flag_C then

         Write_Str ("====  Compiling package spec ");

         Write_Name (Chars (Id));

         Write_Str (" from ");

         Write_Location (Sloc (N));

         Write_Eol;

      end if;

      Analyze (Specification (N));

      Validate_Categorization_Dependency (N, Id);

      End_Package_Scope (Id);

      --  For a compilation unit, indicate whether it needs a body, and

      --  whether elaboration warnings may be meaningful on it.

      if Nkind (Parent (N)) = N_Compilation_Unit then

         Set_Body_Required (Parent (N), Unit_Requires_Body (Id));

         if not Body_Required (Parent (N)) then

            Set_Suppress_Elaboration_Warnings (Id);

         end if;

         Validate_RT_RAT_Component (N);

      end if;

   end Analyze_Package_Declaration;

   -----------------------------------

   -- Analyze_Package_Specification --

   -----------------------------------

   --  Note that this code is shared for the analysis of generic package

   --  specs (see Sem_Ch12.Analyze_Generic_Package_Declaration for details).

   procedure Analyze_Package_Specification (N : Node_Id) is

      Id           : constant Entity_Id  := Defining_Entity (N);

      Orig_Decl    : constant Node_Id    := Original_Node (Parent (N));

      Vis_Decls    : constant List_Id    := Visible_Declarations (N);

      Priv_Decls   : constant List_Id    := Private_Declarations (N);

      E            : Entity_Id;

      L            : Entity_Id;

      Public_Child : Boolean;

      procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id);

      --  Clears constant indications (Never_Set_In_Source, Constant_Value,

      --  and Is_True_Constant) on all variables that are entities of Id,

      --  and on the chain whose first element is FE. A recursive call is

      --  made for all packages and generic packages.

      procedure Generate_Parent_References;

      --  For a child unit, generate references to parent units, for

      --  GPS navigation purposes.

      function Is_Public_Child (Child, Unit : Entity_Id) return Boolean;

      --  Child and Unit are entities of compilation units. True if Child

      --  is a public child of Parent as defined in 10.1.1

      procedure Inspect_Deferred_Constant_Completion;

      --  Examines the deferred constants in the private part of the package

      --  specification. Emits the error message "constant declaration requires

      --  initialization expression " if not completed by an Import pragma.

      procedure Inspect_Unchecked_Union_Completion (Decls : List_Id);

      --  Detects all incomplete or private type declarations having a known

      --  discriminant part that are completed by an Unchecked_Union. Emits

      --  the error message "Unchecked_Union may not complete discriminated

      --  partial view".

      procedure Install_Parent_Private_Declarations (Inst_Id : Entity_Id);

      --  Given the package entity of a generic package instantiation or

      --  formal package whose corresponding generic is a child unit, installs

      --  the private declarations of each of the child unit's parents.

      --  This has to be done at the point of entering the instance package's

      --  private part rather than being done in Sem_Ch12.Install_Parent

      --  (which is where the parents' visible declarations are installed).

      ---------------------

      -- Clear_Constants --

      ---------------------

      procedure Clear_Constants (Id : Entity_Id; FE : Entity_Id) is

         E : Entity_Id;

      begin

         --  Ignore package renamings, not interesting and they can

         --  cause self referential loops in the code below.

         if Nkind (Parent (Id)) = N_Package_Renaming_Declaration then

            return;

         end if;

         --  Note: in the loop below, the check for Next_Entity pointing

         --  back to the package entity seems very odd, but it is needed,

         --  because this kind of unexpected circularity does occur ???

         E := FE;

         while Present (E) and then E /= Id loop

            if Ekind (E) = E_Variable then

               Set_Never_Set_In_Source (E, False);

               Set_Is_True_Constant    (E, False);

               Set_Current_Value       (E, Empty);

               Set_Is_Known_Non_Null   (E, False);

            elsif Ekind (E) = E_Package

                    or else

                  Ekind (E) = E_Generic_Package

            then

               Clear_Constants (E, First_Entity (E));

               Clear_Constants (E, First_Private_Entity (E));

            end if;

            Next_Entity (E);

         end loop;

      end Clear_Constants;

      --------------------------------

      -- Generate_Parent_References --

      --------------------------------

      procedure Generate_Parent_References is

         Decl : constant Node_Id := Parent (N);

      begin

         if Id = Cunit_Entity (Main_Unit)

           or else Parent (Decl) = Library_Unit (Cunit (Main_Unit))

         then

            Generate_Reference (Id, Scope (Id), 'k', False);

         elsif Nkind (Unit (Cunit (Main_Unit))) /= N_Subprogram_Body