FSF GCC merge 02/23/03

[official-gcc.git] / gcc / ada / exp_ch9.adb

------------------------------------------------------------------------------
--                                                                          --
--                         GNAT COMPILER COMPONENTS                         --
--                                                                          --
--                              E X P _ C H 9                               --
--                                                                          --
--                                 B o d y                                  --
--                                                                          --
--                                                                          --
--          Copyright (C) 1992-2002, 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,  59 Temple Place - Suite 330,  Boston, --
-- MA 02111-1307, USA.                                                      --
--                                                                          --
-- GNAT was originally developed  by the GNAT team at  New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc.      --
--                                                                          --
------------------------------------------------------------------------------

with Atree;    use Atree;
with Checks;   use Checks;
with Einfo;    use Einfo;
with Elists;   use Elists;
with Errout;   use Errout;
with Exp_Ch3;  use Exp_Ch3;
with Exp_Ch11; use Exp_Ch11;
with Exp_Ch6;  use Exp_Ch6;
with Exp_Dbug; use Exp_Dbug;
with Exp_Smem; use Exp_Smem;
with Exp_Tss;  use Exp_Tss;
with Exp_Util; use Exp_Util;
with Freeze;   use Freeze;
with Hostparm;
with Namet;    use Namet;
with Nlists;   use Nlists;
with Nmake;    use Nmake;
with Opt;      use Opt;
with Restrict; use Restrict;
with Rtsfind;  use Rtsfind;
with Sem;      use Sem;
with Sem_Ch6;
with Sem_Ch8;  use Sem_Ch8;
with Sem_Ch11; use Sem_Ch11;
with Sem_Elab; use Sem_Elab;
with Sem_Res;  use Sem_Res;
with Sem_Util; use Sem_Util;
with Sinfo;    use Sinfo;
with Snames;   use Snames;
with Stand;    use Stand;
with Tbuild;   use Tbuild;
with Types;    use Types;
with Uintp;    use Uintp;
with Opt;

package body Exp_Ch9 is

   -----------------------
   -- Local Subprograms --
   -----------------------

   function Actual_Index_Expression
     (Sloc  : Source_Ptr;
      Ent   : Entity_Id;
      Index : Node_Id;
      Tsk   : Entity_Id)
      return  Node_Id;
   --  Compute the index position for an entry call. Tsk is the target
   --  task. If the bounds of some entry family depend on discriminants,
   --  the expression computed by this function uses the discriminants
   --  of the target task.

   function Index_Constant_Declaration
     (N        : Node_Id;
      Index_Id : Entity_Id;
      Prot     : Entity_Id)
      return     List_Id;
   --  For an entry family and its barrier function, we define a local entity
   --  that maps the index in the call into the entry index into the object:
   --
   --     I : constant Index_Type := Index_Type'Val (
   --       E - <<index of first family member>> +
   --       Protected_Entry_Index (Index_Type'Pos (Index_Type'First)));

   procedure Add_Object_Pointer
     (Decls : List_Id;
      Pid   : Entity_Id;
      Loc   : Source_Ptr);
   --  Prepend an object pointer declaration to the declaration list
   --  Decls. This object pointer is initialized to a type conversion
   --  of the System.Address pointer passed to entry barrier functions
   --  and entry body procedures.

   function Build_Accept_Body (Astat : Node_Id) return  Node_Id;
   --  Transform accept statement into a block with added exception handler.
   --  Used both for simple accept statements and for accept alternatives in
   --  select statements. Astat is the accept statement.

   function Build_Barrier_Function
     (N    : Node_Id;
      Ent  : Entity_Id;
      Pid  : Node_Id)
      return Node_Id;
   --  Build the function body returning the value of the barrier expression
   --  for the specified entry body.

   function Build_Barrier_Function_Specification
     (Def_Id : Entity_Id;
      Loc    : Source_Ptr)
      return   Node_Id;
   --  Build a specification for a function implementing
   --  the protected entry barrier of the specified entry body.

   function Build_Corresponding_Record
     (N    : Node_Id;
      Ctyp : Node_Id;
      Loc  : Source_Ptr)
      return Node_Id;
   --  Common to tasks and protected types. Copy discriminant specifications,
   --  build record declaration. N is the type declaration, Ctyp is the
   --  concurrent entity (task type or protected type).

   function Build_Entry_Count_Expression
     (Concurrent_Type : Node_Id;
      Component_List  : List_Id;
      Loc             : Source_Ptr)
      return            Node_Id;
   --  Compute number of entries for concurrent object. This is a count of
   --  simple entries, followed by an expression that computes the length
   --  of the range of each entry family. A single array with that size is
   --  allocated for each concurrent object of the type.

   function Build_Find_Body_Index
     (Typ  : Entity_Id)
      return Node_Id;
   --  Build the function that translates the entry index in the call
   --  (which depends on the size of entry families) into an index into the
   --  Entry_Bodies_Array, to determine the body and barrier function used
   --  in a protected entry call. A pointer to this function appears in every
   --  protected object.

   function Build_Find_Body_Index_Spec
     (Typ  : Entity_Id)
      return Node_Id;
   --  Build subprogram declaration for previous one.

   function Build_Protected_Entry
     (N         : Node_Id;
      Ent       : Entity_Id;
      Pid       : Node_Id)
      return Node_Id;
   --  Build the procedure implementing the statement sequence of
   --  the specified entry body.

   function Build_Protected_Entry_Specification
     (Def_Id : Entity_Id;
      Ent_Id : Entity_Id;
      Loc    : Source_Ptr)
      return Node_Id;
   --  Build a specification for a procedure implementing
   --  the statement sequence of the specified entry body.
   --  Add attributes associating it with the entry defining identifier
   --  Ent_Id.

   function Build_Protected_Subprogram_Body
     (N         : Node_Id;
      Pid       : Node_Id;
      N_Op_Spec : Node_Id)
      return      Node_Id;
   --  This function is used to construct the protected version of a protected
   --  subprogram. Its statement sequence first defers abortion, then locks
   --  the associated protected object, and then enters a block that contains
   --  a call to the unprotected version of the subprogram (for details, see
   --  Build_Unprotected_Subprogram_Body). This block statement requires
   --  a cleanup handler that unlocks the object in all cases.
   --  (see Exp_Ch7.Expand_Cleanup_Actions).

   function Build_Protected_Spec
     (N           : Node_Id;
      Obj_Type    : Entity_Id;
      Unprotected : Boolean := False;
      Ident       : Entity_Id)
      return        List_Id;
   --  Utility shared by Build_Protected_Sub_Spec and Expand_Access_Protected_
   --  Subprogram_Type. Builds signature of protected subprogram, adding the
   --  formal that corresponds to the object itself. For an access to protected
   --  subprogram, there is no object type to specify, so the additional
   --  parameter has type Address and mode In. An indirect call through such
   --  a pointer converts the address to a reference to the actual object.
   --  The object is a limited record and therefore a by_reference type.

   function Build_Selected_Name
     (Prefix, Selector : Name_Id;
      Append_Char      : Character := ' ')
      return Name_Id;
   --  Build a name in the form of Prefix__Selector, with an optional
   --  character appended. This is used for internal subprograms generated
   --  for operations of protected types, including barrier functions. In
   --  order to simplify the work of the debugger, the prefix includes the
   --  characters PT.

   procedure Build_Simple_Entry_Call
     (N       : Node_Id;
      Concval : Node_Id;
      Ename   : Node_Id;
      Index   : Node_Id);
   --  Some comments here would be useful ???

   function Build_Task_Proc_Specification (T : Entity_Id) return Node_Id;
   --  This routine constructs a specification for the procedure that we will
   --  build for the task body for task type T. The spec has the form:
   --
   --    procedure tnameB (_Task : access tnameV);
   --
   --  where name is the character name taken from the task type entity that
   --  is passed as the argument to the procedure, and tnameV is the task
   --  value type that is associated with the task type.

   function Build_Unprotected_Subprogram_Body
     (N    : Node_Id;
      Pid  : Node_Id)
      return Node_Id;
   --  This routine constructs the unprotected version of a protected
   --  subprogram body, which is contains all of the code in the
   --  original, unexpanded body. This is the version of the protected
   --  subprogram that is called from all protected operations on the same
   --  object, including the protected version of the same subprogram.

   procedure Collect_Entry_Families
     (Loc          : Source_Ptr;
      Cdecls       : List_Id;
      Current_Node : in out Node_Id;
      Conctyp      : Entity_Id);
   --  For each entry family in a concurrent type, create an anonymous array
   --  type of the right size, and add a component to the corresponding_record.

   function Family_Offset
     (Loc  : Source_Ptr;
      Hi   : Node_Id;
      Lo   : Node_Id;
      Ttyp : Entity_Id)
      return Node_Id;
   --  Compute (Hi - Lo) for two entry family indices. Hi is the index in
   --  an accept statement, or the upper bound in the discrete subtype of
   --  an entry declaration. Lo is the corresponding lower bound. Ttyp is
   --  the concurrent type of the entry.

   function Family_Size
     (Loc  : Source_Ptr;
      Hi   : Node_Id;
      Lo   : Node_Id;
      Ttyp : Entity_Id)
      return Node_Id;
   --  Compute (Hi - Lo) + 1 Max 0, to determine the number of entries in
   --  a family, and handle properly the superflat case. This is equivalent
   --  to the use of 'Length on the index type, but must use Family_Offset
   --  to handle properly the case of bounds that depend on discriminants.

   procedure Extract_Entry
     (N       : Node_Id;
      Concval : out Node_Id;
      Ename   : out Node_Id;
      Index   : out Node_Id);
   --  Given an entry call, returns the associated concurrent object,
   --  the entry name, and the entry family index.

   function Find_Task_Or_Protected_Pragma
     (T    : Node_Id;
      P    : Name_Id)
      return Node_Id;
   --  Searches the task or protected definition T for the first occurrence
   --  of the pragma whose name is given by P. The caller has ensured that
   --  the pragma is present in the task definition. A special case is that
   --  when P is Name_uPriority, the call will also find Interrupt_Priority.
   --  ??? Should be implemented with the rep item chain mechanism.

   procedure Update_Prival_Subtypes (N : Node_Id);
   --  The actual subtypes of the privals will differ from the type of the
   --  private declaration in the original protected type, if the protected
   --  type has discriminants or if the prival has constrained components.
   --  This is because the privals are generated out of sequence w.r.t. the
   --  analysis of a protected body. After generating the bodies for protected
   --  operations, we set correctly the type of all references to privals, by
   --  means of a recursive tree traversal, which is heavy-handed but
   --  correct.

   -----------------------------
   -- Actual_Index_Expression --
   -----------------------------

   function Actual_Index_Expression
     (Sloc  : Source_Ptr;
      Ent   : Entity_Id;
      Index : Node_Id;
      Tsk   : Entity_Id)
      return  Node_Id
   is
      Expr : Node_Id;
      Num  : Node_Id;
      Lo   : Node_Id;
      Hi   : Node_Id;
      Prev : Entity_Id;
      S    : Node_Id;
      Ttyp : Entity_Id := Etype (Tsk);

      --------------------------
      -- Actual_Family_Offset --
      --------------------------

      function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id;
      --  Compute difference between bounds of entry family.

      function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id is

         function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id;
         --  Replace a reference to a discriminant with a selected component
         --  denoting the discriminant of the target task.

         function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id is
            Typ : Entity_Id := Etype (Bound);
            B   : Node_Id;

         begin
            if not Is_Entity_Name (Bound)
              or else Ekind (Entity (Bound)) /= E_Discriminant
            then
               if Nkind (Bound) = N_Attribute_Reference then
                  return Bound;
               else
                  B := New_Copy_Tree (Bound);
               end if;

            else
               B :=
                 Make_Selected_Component (Sloc,
                   Prefix => New_Copy_Tree (Tsk),
                   Selector_Name => New_Occurrence_Of (Entity (Bound), Sloc));

               Analyze_And_Resolve (B, Typ);
            end if;

            return
              Make_Attribute_Reference (Sloc,
                Attribute_Name => Name_Pos,
                Prefix => New_Occurrence_Of (Etype (Bound), Sloc),
                Expressions => New_List (B));
         end Actual_Discriminant_Ref;

      begin
         return
           Make_Op_Subtract (Sloc,
             Left_Opnd  => Actual_Discriminant_Ref (Hi),
             Right_Opnd => Actual_Discriminant_Ref (Lo));
      end Actual_Family_Offset;

   begin
      --  The queues of entries and entry families appear in  textual
      --  order in the associated record. The entry index is computed as
      --  the sum of the number of queues for all entries that precede the
      --  designated one, to which is added the index expression, if this
      --  expression denotes a member of a family.

      --  The following is a place holder for the count of simple entries.

      Num := Make_Integer_Literal (Sloc, 1);

      --  We construct an expression which is a series of addition
      --  operations. See comments in Entry_Index_Expression, which is
      --  identical in structure.

      if Present (Index) then
         S := Etype (Discrete_Subtype_Definition (Declaration_Node (Ent)));

         Expr :=
           Make_Op_Add (Sloc,
             Left_Opnd  => Num,

             Right_Opnd =>
               Actual_Family_Offset (
                 Make_Attribute_Reference (Sloc,
                   Attribute_Name => Name_Pos,
                   Prefix => New_Reference_To (Base_Type (S), Sloc),
                   Expressions => New_List (Relocate_Node (Index))),
                 Type_Low_Bound (S)));
      else
         Expr := Num;
      end if;

      --  Now add lengths of preceding entries and entry families.

      Prev := First_Entity (Ttyp);

      while Chars (Prev) /= Chars (Ent)
        or else (Ekind (Prev) /= Ekind (Ent))
        or else not Sem_Ch6.Type_Conformant (Ent, Prev)
      loop
         if Ekind (Prev) = E_Entry then
            Set_Intval (Num, Intval (Num) + 1);

         elsif Ekind (Prev) = E_Entry_Family then
            S :=
              Etype (Discrete_Subtype_Definition (Declaration_Node (Prev)));
            Lo := Type_Low_Bound  (S);
            Hi := Type_High_Bound (S);

            Expr :=
              Make_Op_Add (Sloc,
              Left_Opnd  => Expr,
              Right_Opnd =>
                Make_Op_Add (Sloc,
                  Left_Opnd =>
                    Actual_Family_Offset (Hi, Lo),
                  Right_Opnd =>
                    Make_Integer_Literal (Sloc, 1)));

         --  Other components are anonymous types to be ignored.

         else
            null;
         end if;

         Next_Entity (Prev);
      end loop;

      return Expr;
   end Actual_Index_Expression;

   ----------------------------------
   -- Add_Discriminal_Declarations --
   ----------------------------------

   procedure Add_Discriminal_Declarations
     (Decls : List_Id;
      Typ   : Entity_Id;
      Name  : Name_Id;
      Loc   : Source_Ptr)
   is
      D     : Entity_Id;

   begin
      if Has_Discriminants (Typ) then
         D := First_Discriminant (Typ);

         while Present (D) loop

            Prepend_To (Decls,
              Make_Object_Renaming_Declaration (Loc,
                Defining_Identifier => Discriminal (D),
                Subtype_Mark => New_Reference_To (Etype (D), Loc),
                Name =>
                  Make_Selected_Component (Loc,
                    Prefix        => Make_Identifier (Loc, Name),
                    Selector_Name => Make_Identifier (Loc, Chars (D)))));

            Next_Discriminant (D);
         end loop;
      end if;
   end Add_Discriminal_Declarations;

   ------------------------
   -- Add_Object_Pointer --
   ------------------------

   procedure Add_Object_Pointer
     (Decls : List_Id;
      Pid   : Entity_Id;
      Loc   : Source_Ptr)
   is
      Obj_Ptr : Node_Id;

   begin
      --  Prepend the declaration of _object. This must be first in the
      --  declaration list, since it is used by the discriminal and
      --  prival declarations.
      --  ??? An attempt to make this a renaming was unsuccessful.
      --
      --     type poVP is access poV;
      --     _object : poVP := poVP!O;

      Obj_Ptr :=
        Make_Defining_Identifier (Loc,
          Chars =>
            New_External_Name
              (Chars (Corresponding_Record_Type (Pid)), 'P'));

      Prepend_To (Decls,
        Make_Object_Declaration (Loc,
          Defining_Identifier =>
            Make_Defining_Identifier (Loc, Name_uObject),
          Object_Definition => New_Reference_To (Obj_Ptr, Loc),
          Expression =>
            Unchecked_Convert_To (Obj_Ptr,
              Make_Identifier (Loc, Name_uO))));

      Prepend_To (Decls,
        Make_Full_Type_Declaration (Loc,
          Defining_Identifier => Obj_Ptr,
          Type_Definition => Make_Access_To_Object_Definition (Loc,
            Subtype_Indication =>
              New_Reference_To (Corresponding_Record_Type (Pid), Loc))));

   end Add_Object_Pointer;

   ------------------------------
   -- Add_Private_Declarations --
   ------------------------------

   procedure Add_Private_Declarations
     (Decls : List_Id;
      Typ   : Entity_Id;
      Name  : Name_Id;
      Loc   : Source_Ptr)
   is
      P        : Node_Id;
      Pdef     : Entity_Id;
      Def      : Node_Id            := Protected_Definition (Parent (Typ));
      Body_Ent : constant Entity_Id := Corresponding_Body (Parent (Typ));

   begin
      pragma Assert (Nkind (Def) = N_Protected_Definition);

      if Present (Private_Declarations (Def)) then
         P := First (Private_Declarations (Def));

         while Present (P) loop
            if Nkind (P) = N_Component_Declaration then
               Pdef := Defining_Identifier (P);
               Prepend_To (Decls,
                 Make_Object_Renaming_Declaration (Loc,
                   Defining_Identifier => Prival (Pdef),
                   Subtype_Mark => New_Reference_To (Etype (Pdef), Loc),
                   Name =>
                     Make_Selected_Component (Loc,
                       Prefix        => Make_Identifier (Loc, Name),
                       Selector_Name => Make_Identifier (Loc, Chars (Pdef)))));
            end if;
            Next (P);
         end loop;
      end if;

      --  One more "prival" for the object itself, with the right protection
      --  type.

      declare
         Protection_Type : RE_Id;
      begin
         if Has_Attach_Handler (Typ) then
            if Restricted_Profile then
               Protection_Type := RE_Protection_Entry;
            else
               Protection_Type := RE_Static_Interrupt_Protection;
            end if;

         elsif Has_Interrupt_Handler (Typ) then
            Protection_Type := RE_Dynamic_Interrupt_Protection;

         elsif Has_Entries (Typ) then
            if Abort_Allowed
              or else Restrictions (No_Entry_Queue) = False
              or else Number_Entries (Typ) > 1
            then
               Protection_Type := RE_Protection_Entries;
            else
               Protection_Type := RE_Protection_Entry;
            end if;

         else
            Protection_Type := RE_Protection;
         end if;

         Prepend_To (Decls,
           Make_Object_Renaming_Declaration (Loc,
             Defining_Identifier => Object_Ref (Body_Ent),
             Subtype_Mark => New_Reference_To (RTE (Protection_Type), Loc),
             Name =>
               Make_Selected_Component (Loc,
                 Prefix        => Make_Identifier (Loc, Name),
                 Selector_Name => Make_Identifier (Loc, Name_uObject))));
      end;

   end Add_Private_Declarations;

   -----------------------
   -- Build_Accept_Body --
   -----------------------

   function Build_Accept_Body (Astat : Node_Id) return  Node_Id is
      Loc     : constant Source_Ptr := Sloc (Astat);
      Stats   : constant Node_Id    := Handled_Statement_Sequence (Astat);
      New_S   : Node_Id;
      Hand    : Node_Id;
      Call    : Node_Id;
      Ohandle : Node_Id;

   begin
      --  At the end of the statement sequence, Complete_Rendezvous is called.
      --  A label skipping the Complete_Rendezvous, and all other
      --  accept processing, has already been added for the expansion
      --  of requeue statements.

      Call := Build_Runtime_Call (Loc, RE_Complete_Rendezvous);
      Insert_Before (Last (Statements (Stats)), Call);
      Analyze (Call);

      --  If exception handlers are present, then append Complete_Rendezvous
      --  calls to the handlers, and construct the required outer block.

      if Present (Exception_Handlers (Stats)) then
         Hand := First (Exception_Handlers (Stats));

         while Present (Hand) loop
            Call := Build_Runtime_Call (Loc, RE_Complete_Rendezvous);
            Append (Call, Statements (Hand));
            Analyze (Call);
            Next (Hand);
         end loop;

         New_S :=
           Make_Handled_Sequence_Of_Statements (Loc,
             Statements => New_List (
               Make_Block_Statement (Loc,
               Handled_Statement_Sequence => Stats)));

      else
         New_S := Stats;
      end if;

      --  At this stage we know that the new statement sequence does not
      --  have an exception handler part, so we supply one to call
      --  Exceptional_Complete_Rendezvous. This handler is

      --    when all others =>
      --       Exceptional_Complete_Rendezvous (Get_GNAT_Exception);

      --  We handle Abort_Signal to make sure that we properly catch the abort
      --  case and wake up the caller.

      Ohandle := Make_Others_Choice (Loc);
      Set_All_Others (Ohandle);

      Set_Exception_Handlers (New_S,
        New_List (
          Make_Exception_Handler (Loc,
            Exception_Choices => New_List (Ohandle),

            Statements =>  New_List (
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (
                  RTE (RE_Exceptional_Complete_Rendezvous), Loc),
                Parameter_Associations => New_List (
                  Make_Function_Call (Loc,
                    Name => New_Reference_To (
                      RTE (RE_Get_GNAT_Exception), Loc))))))));

      Set_Parent (New_S, Astat); -- temp parent for Analyze call
      Analyze_Exception_Handlers (Exception_Handlers (New_S));
      Expand_Exception_Handlers (New_S);

      --  Exceptional_Complete_Rendezvous must be called with abort
      --  still deferred, which is the case for a "when all others" handler.

      return New_S;

   end Build_Accept_Body;

   -----------------------------------
   -- Build_Activation_Chain_Entity --
   -----------------------------------

   procedure Build_Activation_Chain_Entity (N : Node_Id) is
      P     : Node_Id;
      B     : Node_Id;
      Decls : List_Id;

   begin
      --  Loop to find enclosing construct containing activation chain variable

      P := Parent (N);

      while Nkind (P) /= N_Subprogram_Body
        and then Nkind (P) /= N_Package_Declaration
        and then Nkind (P) /= N_Package_Body
        and then Nkind (P) /= N_Block_Statement
        and then Nkind (P) /= N_Task_Body
      loop
         P := Parent (P);
      end loop;

      --  If we are in a package body, the activation chain variable is
      --  allocated in the corresponding spec. First, we save the package
      --  body node because we enter the new entity in its Declarations list.

      B := P;

      if Nkind (P) = N_Package_Body then
         P := Unit_Declaration_Node (Corresponding_Spec (P));
         Decls := Declarations (B);

      elsif Nkind (P) = N_Package_Declaration then
         Decls := Visible_Declarations (Specification (B));

      else
         Decls := Declarations (B);
      end if;

      --  If activation chain entity not already declared, declare it

      if No (Activation_Chain_Entity (P)) then
         Set_Activation_Chain_Entity
           (P, Make_Defining_Identifier (Sloc (N), Name_uChain));

         Prepend_To (Decls,
           Make_Object_Declaration (Sloc (P),
             Defining_Identifier => Activation_Chain_Entity (P),
             Aliased_Present => True,
             Object_Definition   =>
               New_Reference_To (RTE (RE_Activation_Chain), Sloc (P))));

         Analyze (First (Decls));
      end if;

   end Build_Activation_Chain_Entity;

   ----------------------------
   -- Build_Barrier_Function --
   ----------------------------

   function Build_Barrier_Function
     (N    : Node_Id;
      Ent  : Entity_Id;
      Pid  : Node_Id)
      return Node_Id
   is
      Loc         : constant Source_Ptr := Sloc (N);
      Ent_Formals : constant Node_Id    := Entry_Body_Formal_Part (N);
      Index_Spec  : constant Node_Id    := Entry_Index_Specification
                                             (Ent_Formals);
      Bdef        : Entity_Id;
      Bspec       : Node_Id;
      Op_Decls    : List_Id := New_List;

   begin
      Bdef :=
        Make_Defining_Identifier (Loc, Chars (Barrier_Function (Ent)));
      Bspec := Build_Barrier_Function_Specification (Bdef, Loc);

      --  <object pointer declaration>
      --  <discriminant renamings>
      --  <private object renamings>
      --  Add discriminal and private renamings. These names have
      --  already been used to expand references to discriminants
      --  and private data.

      Add_Discriminal_Declarations (Op_Decls, Pid, Name_uObject, Loc);
      Add_Private_Declarations (Op_Decls, Pid, Name_uObject, Loc);
      Add_Object_Pointer (Op_Decls, Pid, Loc);

      --  If this is the barrier for an entry family, the entry index is
      --  visible in the body of the barrier. Create a local variable that
      --  converts the entry index (which is the last formal of the barrier
      --  function) into the appropriate offset into the entry array. The
      --  entry index constant must be set, as for the entry body, so that
      --  local references to the entry index are correctly replaced with
      --  the local variable. This parallels what is done for entry bodies.

      if Present (Index_Spec) then
         declare
            Index_Id  : constant Entity_Id := Defining_Identifier (Index_Spec);
            Index_Con : constant Entity_Id :=
              Make_Defining_Identifier (Loc, New_Internal_Name ('I'));

         begin
            Set_Entry_Index_Constant (Index_Id, Index_Con);
            Append_List_To (Op_Decls,
              Index_Constant_Declaration (N, Index_Id, Pid));
         end;
      end if;

      --  Note: the condition in the barrier function needs to be properly
      --  processed for the C/Fortran boolean possibility, but this happens
      --  automatically since the return statement does this normalization.

      return
        Make_Subprogram_Body (Loc,
          Specification => Bspec,
          Declarations => Op_Decls,
          Handled_Statement_Sequence =>
            Make_Handled_Sequence_Of_Statements (Loc,
              Statements => New_List (
                Make_Return_Statement (Loc,
                  Expression => Condition (Ent_Formals)))));
   end Build_Barrier_Function;

   ------------------------------------------
   -- Build_Barrier_Function_Specification --
   ------------------------------------------

   function Build_Barrier_Function_Specification
     (Def_Id : Entity_Id;
      Loc    : Source_Ptr)
      return   Node_Id
   is
   begin
      return Make_Function_Specification (Loc,
        Defining_Unit_Name => Def_Id,
        Parameter_Specifications => New_List (
          Make_Parameter_Specification (Loc,
            Defining_Identifier => Make_Defining_Identifier (Loc, Name_uO),
            Parameter_Type =>
              New_Reference_To (RTE (RE_Address), Loc)),

          Make_Parameter_Specification (Loc,
            Defining_Identifier => Make_Defining_Identifier (Loc, Name_uE),
            Parameter_Type =>
              New_Reference_To (RTE (RE_Protected_Entry_Index), Loc))),

        Subtype_Mark => New_Reference_To (Standard_Boolean, Loc));
   end Build_Barrier_Function_Specification;

   --------------------------
   -- Build_Call_With_Task --
   --------------------------

   function Build_Call_With_Task
     (N    : Node_Id;
      E    : Entity_Id)
      return Node_Id
   is
      Loc : constant Source_Ptr := Sloc (N);

   begin
      return
        Make_Function_Call (Loc,
          Name => New_Reference_To (E, Loc),
          Parameter_Associations => New_List (Concurrent_Ref (N)));
   end Build_Call_With_Task;

   --------------------------------
   -- Build_Corresponding_Record --
   --------------------------------

   function Build_Corresponding_Record
    (N    : Node_Id;
     Ctyp : Entity_Id;
     Loc  : Source_Ptr)
     return Node_Id
   is
      Rec_Ent  : constant Entity_Id :=
                   Make_Defining_Identifier
                     (Loc, New_External_Name (Chars (Ctyp), 'V'));
      Disc     : Entity_Id;
      Dlist    : List_Id;
      New_Disc : Entity_Id;
      Cdecls   : List_Id;

   begin
      Set_Corresponding_Record_Type (Ctyp, Rec_Ent);
      Set_Ekind (Rec_Ent, E_Record_Type);
      Set_Has_Delayed_Freeze (Rec_Ent, Has_Delayed_Freeze (Ctyp));
      Set_Is_Concurrent_Record_Type (Rec_Ent, True);
      Set_Corresponding_Concurrent_Type (Rec_Ent, Ctyp);
      Set_Girder_Constraint (Rec_Ent, No_Elist);
      Cdecls := New_List;

      --  Use discriminals to create list of discriminants for record, and
      --  create new discriminals for use in default expressions, etc. It is
      --  worth noting that a task discriminant gives rise to 5 entities;

      --  a) The original discriminant.
      --  b) The discriminal for use in the task.
      --  c) The discriminant of the corresponding record.
      --  d) The discriminal for the init_proc of the corresponding record.
      --  e) The local variable that renames the discriminant in the procedure
      --     for the task body.

      --  In fact the discriminals b) are used in the renaming declarations
      --  for e). See details in  einfo (Handling of Discriminants).

      if Present (Discriminant_Specifications (N)) then
         Dlist := New_List;
         Disc := First_Discriminant (Ctyp);

         while Present (Disc) loop
            New_Disc := CR_Discriminant (Disc);

            Append_To (Dlist,
              Make_Discriminant_Specification (Loc,
                Defining_Identifier => New_Disc,
                Discriminant_Type =>
                  New_Occurrence_Of (Etype (Disc), Loc),
                Expression =>
                  New_Copy (Discriminant_Default_Value (Disc))));

            Next_Discriminant (Disc);
         end loop;

      else
         Dlist := No_List;
      end if;

      --  Now we can construct the record type declaration. Note that this
      --  record is limited, reflecting the underlying limitedness of the
      --  task or protected object that it represents, and ensuring for
      --  example that it is properly passed by reference.

      return
        Make_Full_Type_Declaration (Loc,
          Defining_Identifier => Rec_Ent,
          Discriminant_Specifications => Dlist,
          Type_Definition =>
            Make_Record_Definition (Loc,
              Component_List =>
                Make_Component_List (Loc,
                  Component_Items => Cdecls),
              Limited_Present => True));
   end Build_Corresponding_Record;

   ----------------------------------
   -- Build_Entry_Count_Expression --
   ----------------------------------

   function Build_Entry_Count_Expression
     (Concurrent_Type : Node_Id;
      Component_List  : List_Id;
      Loc             : Source_Ptr)
      return            Node_Id
   is
      Eindx  : Nat;
      Ent    : Entity_Id;
      Ecount : Node_Id;
      Comp   : Node_Id;
      Lo     : Node_Id;
      Hi     : Node_Id;
      Typ    : Entity_Id;

   begin
      Ent := First_Entity (Concurrent_Type);
      Eindx := 0;

      --  Count number of non-family entries

      while Present (Ent) loop
         if Ekind (Ent) = E_Entry then
            Eindx := Eindx + 1;
         end if;

         Next_Entity (Ent);
      end loop;

      Ecount := Make_Integer_Literal (Loc, Eindx);

      --  Loop through entry families building the addition nodes

      Ent := First_Entity (Concurrent_Type);
      Comp := First (Component_List);

      while Present (Ent) loop
         if Ekind (Ent) = E_Entry_Family then
            while Chars (Ent) /= Chars (Defining_Identifier (Comp)) loop
               Next (Comp);
            end loop;

            Typ := Etype (Discrete_Subtype_Definition (Parent (Ent)));
            Hi := Type_High_Bound (Typ);
            Lo := Type_Low_Bound  (Typ);

            Ecount :=
              Make_Op_Add (Loc,
                Left_Opnd  => Ecount,
                Right_Opnd => Family_Size (Loc, Hi, Lo, Concurrent_Type));
         end if;

         Next_Entity (Ent);
      end loop;

      return Ecount;
   end Build_Entry_Count_Expression;

   ---------------------------
   -- Build_Find_Body_Index --
   ---------------------------

   function Build_Find_Body_Index
      (Typ : Entity_Id)
      return Node_Id
   is
      Loc   : constant Source_Ptr := Sloc (Typ);
      Ent   : Entity_Id;
      E_Typ : Entity_Id;
      Has_F : Boolean := False;
      Index : Nat;
      If_St : Node_Id := Empty;
      Lo    : Node_Id;
      Hi    : Node_Id;
      Decls : List_Id := New_List;
      Ret   : Node_Id;
      Spec  : Node_Id;
      Siz   : Node_Id := Empty;

      procedure Add_If_Clause (Expr : Node_Id);
      --  Add test for range of current entry.

      function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id;
      --  If a bound of an entry is given by a discriminant, retrieve the
      --  actual value of the discriminant from the enclosing object.

      -------------------
      -- Add_If_Clause --
      -------------------

      procedure Add_If_Clause (Expr : Node_Id) is
         Cond  : Node_Id;
         Stats : constant List_Id :=
                   New_List (
                     Make_Return_Statement (Loc,
                       Expression => Make_Integer_Literal (Loc, Index + 1)));

      begin
         --  Index for current entry body.

         Index := Index + 1;

         --  Compute total length of entry queues so far.

         if No (Siz) then
            Siz := Expr;
         else
            Siz :=
              Make_Op_Add (Loc,
                Left_Opnd => Siz,
                Right_Opnd => Expr);
         end if;

         Cond :=
           Make_Op_Le (Loc,
             Left_Opnd => Make_Identifier (Loc, Name_uE),
             Right_Opnd => Siz);

         --  Map entry queue indices in the range of the current family
         --  into the current index, that designates the entry body.

         if No (If_St) then
            If_St :=
              Make_Implicit_If_Statement (Typ,
                Condition => Cond,
                Then_Statements => Stats,
                Elsif_Parts   => New_List);

            Ret := If_St;

         else
            Append (
              Make_Elsif_Part (Loc,
                Condition => Cond,
                Then_Statements => Stats),
              Elsif_Parts (If_St));
         end if;

      end Add_If_Clause;

      ------------------------------
      -- Convert_Discriminant_Ref --
      ------------------------------

      function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id is
         B   : Node_Id;

      begin
         if Is_Entity_Name (Bound)
           and then Ekind (Entity (Bound)) = E_Discriminant
         then
            B :=
              Make_Selected_Component (Loc,
               Prefix =>
                 Unchecked_Convert_To (Corresponding_Record_Type (Typ),
                   Make_Explicit_Dereference (Loc,
                     Make_Identifier (Loc, Name_uObject))),
               Selector_Name => Make_Identifier (Loc, Chars (Bound)));
            Set_Etype (B, Etype (Entity (Bound)));
         else
            B := New_Copy_Tree (Bound);
         end if;

         return B;
      end Convert_Discriminant_Ref;

   --  Start of processing for Build_Find_Body_Index

   begin
      Spec := Build_Find_Body_Index_Spec (Typ);

      Ent := First_Entity (Typ);

      while Present (Ent) loop

         if Ekind (Ent) = E_Entry_Family then
            Has_F := True;
            exit;
         end if;

         Next_Entity (Ent);
      end loop;

      if not Has_F then

         --  If the protected type has no entry families, there is a one-one
         --  correspondence between entry queue and entry body.

         Ret :=
           Make_Return_Statement (Loc,
             Expression => Make_Identifier (Loc, Name_uE));

      else
         --  Suppose entries e1, e2, ... have size l1, l2, ... we generate
         --  the following:
         --
         --  if E <= l1 then return 1;
         --  elsif E <= l1 + l2 then return 2;
         --  ...

         Index := 0;
         Siz   := Empty;
         Ent   := First_Entity (Typ);

         Add_Object_Pointer (Decls, Typ, Loc);

         while Present (Ent) loop

            if Ekind (Ent) = E_Entry then
               Add_If_Clause (Make_Integer_Literal (Loc, 1));

            elsif Ekind (Ent) = E_Entry_Family then

               E_Typ := Etype (Discrete_Subtype_Definition (Parent (Ent)));
               Hi := Convert_Discriminant_Ref (Type_High_Bound (E_Typ));
               Lo := Convert_Discriminant_Ref (Type_Low_Bound  (E_Typ));
               Add_If_Clause (Family_Size (Loc, Hi, Lo, Typ));
            end if;

            Next_Entity (Ent);
         end loop;

         if Index = 1 then
            Decls := New_List;
            Ret :=
              Make_Return_Statement (Loc,
                Expression => Make_Integer_Literal (Loc, 1));

         elsif Nkind (Ret) = N_If_Statement then

            --  Ranges are in increasing order, so last one doesn't need a
            --  guard.

            declare
               Nod : constant Node_Id := Last (Elsif_Parts (Ret));

            begin
               Remove (Nod);
               Set_Else_Statements (Ret, Then_Statements (Nod));
            end;
         end if;
      end if;

      return
        Make_Subprogram_Body (Loc,
          Specification => Spec,
          Declarations  => Decls,
          Handled_Statement_Sequence =>
            Make_Handled_Sequence_Of_Statements (Loc,
              Statements => New_List (Ret)));

   end Build_Find_Body_Index;

   --------------------------------
   -- Build_Find_Body_Index_Spec --
   --------------------------------

   function Build_Find_Body_Index_Spec
      (Typ : Entity_Id)
      return Node_Id
   is
      Loc   : constant Source_Ptr := Sloc (Typ);
      Id    : constant Entity_Id :=
               Make_Defining_Identifier (Loc,
                 Chars => New_External_Name (Chars (Typ), 'F'));
      Parm1 : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uO);
      Parm2 : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uE);

   begin
      return
        Make_Function_Specification (Loc,
          Defining_Unit_Name => Id,
          Parameter_Specifications => New_List (
            Make_Parameter_Specification (Loc,
              Defining_Identifier => Parm1,
              Parameter_Type =>
                New_Reference_To (RTE (RE_Address), Loc)),

            Make_Parameter_Specification (Loc,
              Defining_Identifier => Parm2,
              Parameter_Type =>
                New_Reference_To (RTE (RE_Protected_Entry_Index), Loc))),
          Subtype_Mark => New_Occurrence_Of (
            RTE (RE_Protected_Entry_Index), Loc));

   end Build_Find_Body_Index_Spec;

   -------------------------
   -- Build_Master_Entity --
   -------------------------

   procedure Build_Master_Entity (E : Entity_Id) is
      Loc  : constant Source_Ptr := Sloc (E);
      P    : Node_Id;
      Decl : Node_Id;

   begin
      --  Nothing to do if we already built a master entity for this scope
      --  or if there is no task hierarchy.

      if Has_Master_Entity (Scope (E))
        or else Restrictions (No_Task_Hierarchy)
      then
         return;
      end if;

      --  Otherwise first build the master entity
      --    _Master : constant Master_Id := Current_Master.all;
      --  and insert it just before the current declaration

      Decl :=
        Make_Object_Declaration (Loc,
          Defining_Identifier =>
            Make_Defining_Identifier (Loc, Name_uMaster),
          Constant_Present => True,
          Object_Definition => New_Reference_To (RTE (RE_Master_Id), Loc),
          Expression =>
            Make_Explicit_Dereference (Loc,
              New_Reference_To (RTE (RE_Current_Master), Loc)));

      P := Parent (E);
      Insert_Before (P, Decl);
      Analyze (Decl);
      Set_Has_Master_Entity (Scope (E));

      --  Now mark the containing scope as a task master

      while Nkind (P) /= N_Compilation_Unit loop
         P := Parent (P);

         --  If we fall off the top, we are at the outer level, and the
         --  environment task is our effective master, so nothing to mark.

         if Nkind (P) = N_Task_Body
           or else Nkind (P) = N_Block_Statement
           or else Nkind (P) = N_Subprogram_Body
         then
            Set_Is_Task_Master (P, True);
            return;

         elsif Nkind (Parent (P)) = N_Subunit then
            P := Corresponding_Stub (Parent (P));
         end if;
      end loop;
   end Build_Master_Entity;

   ---------------------------
   -- Build_Protected_Entry --
   ---------------------------

   function Build_Protected_Entry
     (N    : Node_Id;
      Ent  : Entity_Id;
      Pid  : Node_Id)
      return Node_Id
   is
      Loc      : constant Source_Ptr := Sloc (N);
      Edef     : Entity_Id;
      Espec    : Node_Id;
      Op_Decls : List_Id := New_List;
      Op_Stats : List_Id;
      Ohandle  : Node_Id;
      Complete : Node_Id;

   begin
      Edef :=
        Make_Defining_Identifier (Loc,
          Chars => Chars (Protected_Body_Subprogram (Ent)));
      Espec := Build_Protected_Entry_Specification (Edef, Empty, Loc);

      --  <object pointer declaration>
      --  Add object pointer declaration. This is needed by the
      --  discriminal and prival renamings, which should already
      --  have been inserted into the declaration list.

      Add_Object_Pointer (Op_Decls, Pid, Loc);

      if Abort_Allowed
        or else Restrictions (No_Entry_Queue) = False
        or else Number_Entries (Pid) > 1
      then
         Complete := New_Reference_To (RTE (RE_Complete_Entry_Body), Loc);
      else
         Complete :=
           New_Reference_To (RTE (RE_Complete_Single_Entry_Body), Loc);
      end if;

      Op_Stats := New_List (
         Make_Block_Statement (Loc,
           Declarations => Declarations (N),
           Handled_Statement_Sequence =>
             Handled_Statement_Sequence (N)),

         Make_Procedure_Call_Statement (Loc,
           Name => Complete,
           Parameter_Associations => New_List (
             Make_Attribute_Reference (Loc,
               Prefix =>
                 Make_Selected_Component (Loc,
                   Prefix =>
                     Make_Identifier (Loc, Name_uObject),

                   Selector_Name =>
                     Make_Identifier (Loc, Name_uObject)),
                 Attribute_Name => Name_Unchecked_Access))));

      if Restrictions (No_Exception_Handlers) then
         return
           Make_Subprogram_Body (Loc,
             Specification => Espec,
             Declarations => Op_Decls,
             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc, Op_Stats));

      else
         Ohandle := Make_Others_Choice (Loc);
         Set_All_Others (Ohandle);

         if Abort_Allowed
           or else Restrictions (No_Entry_Queue) = False
           or else Number_Entries (Pid) > 1
         then
            Complete :=
              New_Reference_To (RTE (RE_Exceptional_Complete_Entry_Body), Loc);

         else
            Complete := New_Reference_To (
              RTE (RE_Exceptional_Complete_Single_Entry_Body), Loc);
         end if;

         return
           Make_Subprogram_Body (Loc,
             Specification => Espec,
             Declarations => Op_Decls,
             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc,
                 Statements => Op_Stats,
                 Exception_Handlers => New_List (
                   Make_Exception_Handler (Loc,
                     Exception_Choices => New_List (Ohandle),

                     Statements =>  New_List (
                       Make_Procedure_Call_Statement (Loc,
                         Name => Complete,
                         Parameter_Associations => New_List (
                           Make_Attribute_Reference (Loc,
                             Prefix =>
                               Make_Selected_Component (Loc,
                                 Prefix =>
                                   Make_Identifier (Loc, Name_uObject),
                                 Selector_Name =>
                                   Make_Identifier (Loc, Name_uObject)),
                               Attribute_Name => Name_Unchecked_Access),

                           Make_Function_Call (Loc,
                             Name => New_Reference_To (
                               RTE (RE_Get_GNAT_Exception), Loc)))))))));
      end if;
   end Build_Protected_Entry;

   -----------------------------------------
   -- Build_Protected_Entry_Specification --
   -----------------------------------------

   function Build_Protected_Entry_Specification
     (Def_Id : Entity_Id;
      Ent_Id : Entity_Id;
      Loc    : Source_Ptr)
      return   Node_Id
   is
      P : Entity_Id;

   begin
      P := Make_Defining_Identifier (Loc, Name_uP);

      if Present (Ent_Id) then
         Append_Elmt (P, Accept_Address (Ent_Id));
      end if;

      return Make_Procedure_Specification (Loc,
        Defining_Unit_Name => Def_Id,
        Parameter_Specifications => New_List (
          Make_Parameter_Specification (Loc,
            Defining_Identifier => Make_Defining_Identifier (Loc, Name_uO),
            Parameter_Type =>
              New_Reference_To (RTE (RE_Address), Loc)),

          Make_Parameter_Specification (Loc,
            Defining_Identifier => P,
            Parameter_Type =>
              New_Reference_To (RTE (RE_Address), Loc)),

          Make_Parameter_Specification (Loc,
            Defining_Identifier => Make_Defining_Identifier (Loc, Name_uE),
            Parameter_Type =>
              New_Reference_To (RTE (RE_Protected_Entry_Index), Loc))));
   end Build_Protected_Entry_Specification;

   --------------------------
   -- Build_Protected_Spec --
   --------------------------

   function Build_Protected_Spec
     (N           : Node_Id;
      Obj_Type    : Entity_Id;
      Unprotected : Boolean := False;
      Ident       : Entity_Id)
      return        List_Id
   is
      Loc         : constant Source_Ptr := Sloc (N);
      Formal      : Entity_Id;
      New_Plist   : List_Id;
      New_Param   : Node_Id;

   begin
      New_Plist := New_List;
      Formal := First_Formal (Ident);

      while Present (Formal) loop
         New_Param :=
           Make_Parameter_Specification (Loc,
             Defining_Identifier =>
               Make_Defining_Identifier (Sloc (Formal), Chars (Formal)),
             In_Present => In_Present (Parent (Formal)),
             Out_Present => Out_Present (Parent (Formal)),
             Parameter_Type =>
               New_Reference_To (Etype (Formal), Loc));

         if Unprotected then
            Set_Protected_Formal (Formal, Defining_Identifier (New_Param));
         end if;

         Append (New_Param, New_Plist);
         Next_Formal (Formal);
      end loop;

      --  If the subprogram is a procedure and the context is not an access
      --  to protected subprogram, the parameter is in-out. Otherwise it is
      --  an in parameter.

      Prepend_To (New_Plist,
        Make_Parameter_Specification (Loc,
          Defining_Identifier =>
            Make_Defining_Identifier (Loc, Name_uObject),
          In_Present => True,
          Out_Present =>
           (Etype (Ident) = Standard_Void_Type
              and then not Is_RTE (Obj_Type, RE_Address)),
          Parameter_Type => New_Reference_To (Obj_Type, Loc)));

      return New_Plist;
   end Build_Protected_Spec;

   ---------------------------------------
   -- Build_Protected_Sub_Specification --
   ---------------------------------------

   function Build_Protected_Sub_Specification
     (N           : Node_Id;
      Prottyp     : Entity_Id;
      Unprotected : Boolean := False)
      return        Node_Id
   is
      Loc         : constant Source_Ptr := Sloc (N);
      Decl        : Node_Id;
      Protnm      : constant Name_Id := Chars (Prottyp);
      Ident       : Entity_Id;
      Nam         : Name_Id;
      New_Plist   : List_Id;
      Append_Char : Character;
      New_Spec    : Node_Id;

   begin
      if Ekind
         (Defining_Unit_Name (Specification (N))) = E_Subprogram_Body
      then
         Decl := Unit_Declaration_Node (Corresponding_Spec (N));
      else
         Decl := N;
      end if;

      Ident := Defining_Unit_Name (Specification (Decl));
      Nam := Chars (Ident);

      New_Plist := Build_Protected_Spec
                        (Decl, Corresponding_Record_Type (Prottyp),
                         Unprotected, Ident);

      if Unprotected then
         Append_Char := 'N';
      else
         Append_Char := 'P';
      end if;

      if Nkind (Specification (Decl)) = N_Procedure_Specification then
         return
           Make_Procedure_Specification (Loc,
             Defining_Unit_Name =>
               Make_Defining_Identifier (Loc,
                 Chars => Build_Selected_Name (Protnm, Nam, Append_Char)),
             Parameter_Specifications => New_Plist);

      else
         New_Spec :=
           Make_Function_Specification (Loc,
             Defining_Unit_Name =>
               Make_Defining_Identifier (Loc,
                 Chars => Build_Selected_Name (Protnm, Nam, Append_Char)),
             Parameter_Specifications => New_Plist,
             Subtype_Mark => New_Copy (Subtype_Mark (Specification (Decl))));
         Set_Return_Present (Defining_Unit_Name (New_Spec));
         return New_Spec;
      end if;
   end Build_Protected_Sub_Specification;

   -------------------------------------
   -- Build_Protected_Subprogram_Body --
   -------------------------------------

   function Build_Protected_Subprogram_Body
     (N         : Node_Id;
      Pid       : Node_Id;
      N_Op_Spec : Node_Id)
      return      Node_Id
   is
      Loc          : constant Source_Ptr := Sloc (N);
      Op_Spec      : Node_Id;
      Op_Def       : Entity_Id;
      Sub_Name     : Name_Id;
      P_Op_Spec    : Node_Id;
      Uactuals     : List_Id;
      Pformal      : Node_Id;
      Unprot_Call  : Node_Id;
      Sub_Body     : Node_Id;
      Lock_Name    : Node_Id;
      Lock_Stmt    : Node_Id;
      Unlock_Name  : Node_Id;
      Unlock_Stmt  : Node_Id;
      Service_Name : Node_Id;
      Service_Stmt : Node_Id;
      R            : Node_Id;
      Return_Stmt  : Node_Id := Empty;
      Pre_Stmts    : List_Id := No_List;
      --   Initializations to avoid spurious warnings from GCC3.
      Stmts        : List_Id;
      Object_Parm  : Node_Id;
      Exc_Safe     : Boolean;

      function Is_Exception_Safe (Subprogram : Node_Id) return Boolean;
      --  Tell whether a given subprogram cannot raise an exception

      -----------------------
      -- Is_Exception_Safe --
      -----------------------

      function Is_Exception_Safe (Subprogram : Node_Id) return Boolean is

         function Has_Side_Effect (N : Node_Id) return Boolean;
         --  Return True whenever encountering a subprogram call or a
         --  raise statement of any kind in the sequence of statements N

         ---------------------
         -- Has_Side_Effect --
         ---------------------

         --  What is this doing buried two levels down in exp_ch9. It
         --  seems like a generally useful function, and indeed there
         --  may be code duplication going on here ???

         function Has_Side_Effect (N : Node_Id) return Boolean is
            Stmt : Node_Id := N;
            Expr : Node_Id;

            function Is_Call_Or_Raise (N : Node_Id) return Boolean;
            --  Indicate whether N is a subprogram call or a raise statement

            function Is_Call_Or_Raise (N : Node_Id) return Boolean is
            begin
               return Nkind (N) = N_Procedure_Call_Statement
                 or else Nkind (N) = N_Function_Call
                 or else Nkind (N) = N_Raise_Statement
                 or else Nkind (N) = N_Raise_Constraint_Error
                 or else Nkind (N) = N_Raise_Program_Error
                 or else Nkind (N) = N_Raise_Storage_Error;
            end Is_Call_Or_Raise;

         --  Start of processing for Has_Side_Effect

         begin
            while Present (Stmt) loop
               if Is_Call_Or_Raise (Stmt) then
                  return True;
               end if;

               --  An object declaration can also contain a function call
               --  or a raise statement

               if Nkind (Stmt) = N_Object_Declaration then
                  Expr := Expression (Stmt);

                  if Present (Expr) and then Is_Call_Or_Raise (Expr) then
                     return True;
                  end if;
               end if;

               Next (Stmt);
            end loop;

            return False;
         end Has_Side_Effect;

      --  Start of processing for Is_Exception_Safe

      begin
         --  If the checks handled by the back end are not disabled, we cannot
         --  ensure that no exception will be raised.

         if not Access_Checks_Suppressed (Empty)
           or else not Discriminant_Checks_Suppressed (Empty)
           or else not Range_Checks_Suppressed (Empty)
           or else not Index_Checks_Suppressed (Empty)
           or else Opt.Stack_Checking_Enabled
         then
            return False;
         end if;

         if Has_Side_Effect (First (Declarations (Subprogram)))
           or else
              Has_Side_Effect (
                First (Statements (Handled_Statement_Sequence (Subprogram))))
         then
            return False;
         else
            return True;
         end if;
      end Is_Exception_Safe;

   --  Start of processing for Build_Protected_Subprogram_Body

   begin
      Op_Spec := Specification (N);
      Op_Def := Defining_Unit_Name (Op_Spec);
      Exc_Safe := Is_Exception_Safe (N);

      Sub_Name := Chars (Defining_Unit_Name (Specification (N)));

      P_Op_Spec :=
        Build_Protected_Sub_Specification (N,
          Pid, Unprotected => False);

      --  Build a list of the formal parameters of the protected
      --  version of the subprogram to use as the actual parameters
      --  of the unprotected version.

      Uactuals := New_List;
      Pformal := First (Parameter_Specifications (P_Op_Spec));

      while Present (Pformal) loop
         Append (
           Make_Identifier (Loc, Chars (Defining_Identifier (Pformal))),
           Uactuals);
         Next (Pformal);
      end loop;

      --  Make a call to the unprotected version of the subprogram
      --  built above for use by the protected version built below.

      if Nkind (Op_Spec) = N_Function_Specification then
         if Exc_Safe then
            R := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
            Unprot_Call :=
              Make_Object_Declaration (Loc,
                Defining_Identifier => R,
                Constant_Present => True,
                Object_Definition => New_Copy (Subtype_Mark (N_Op_Spec)),
                Expression =>
                  Make_Function_Call (Loc,
                    Name => Make_Identifier (Loc,
                      Chars (Defining_Unit_Name (N_Op_Spec))),
                    Parameter_Associations => Uactuals));
            Return_Stmt := Make_Return_Statement (Loc,
              Expression => New_Reference_To (R, Loc));

         else
            Unprot_Call := Make_Return_Statement (Loc,
              Expression => Make_Function_Call (Loc,
                Name =>
                  Make_Identifier (Loc,
                    Chars (Defining_Unit_Name (N_Op_Spec))),
                Parameter_Associations => Uactuals));
         end if;

      else
         Unprot_Call := Make_Procedure_Call_Statement (Loc,
           Name =>
             Make_Identifier (Loc,
               Chars (Defining_Unit_Name (N_Op_Spec))),
           Parameter_Associations => Uactuals);
      end if;

      --  Wrap call in block that will be covered by an at_end handler.

      if not Exc_Safe then
         Unprot_Call := Make_Block_Statement (Loc,
           Handled_Statement_Sequence =>
             Make_Handled_Sequence_Of_Statements (Loc,
               Statements => New_List (Unprot_Call)));
      end if;

      --  Make the protected subprogram body. This locks the protected
      --  object and calls the unprotected version of the subprogram.

      --  If the protected object is controlled (i.e it has entries or
      --  needs finalization for interrupt handling), call Lock_Entries,
      --  except if the protected object follows the Ravenscar profile, in
      --  which case call Lock_Entry, otherwise call the simplified version,
      --  Lock.

      if Has_Entries (Pid)
        or else Has_Interrupt_Handler (Pid)
        or else Has_Attach_Handler (Pid)
      then
         if Abort_Allowed
           or else Restrictions (No_Entry_Queue) = False
           or else Number_Entries (Pid) > 1
         then
            Lock_Name := New_Reference_To (RTE (RE_Lock_Entries), Loc);
            Unlock_Name := New_Reference_To (RTE (RE_Unlock_Entries), Loc);
            Service_Name := New_Reference_To (RTE (RE_Service_Entries), Loc);

         else
            Lock_Name := New_Reference_To (RTE (RE_Lock_Entry), Loc);
            Unlock_Name := New_Reference_To (RTE (RE_Unlock_Entry), Loc);
            Service_Name := New_Reference_To (RTE (RE_Service_Entry), Loc);
         end if;

      else
         Lock_Name := New_Reference_To (RTE (RE_Lock), Loc);
         Unlock_Name := New_Reference_To (RTE (RE_Unlock), Loc);
         Service_Name := Empty;
      end if;

      Object_Parm :=
        Make_Attribute_Reference (Loc,
           Prefix =>
             Make_Selected_Component (Loc,
               Prefix =>
                 Make_Identifier (Loc, Name_uObject),
             Selector_Name =>
                 Make_Identifier (Loc, Name_uObject)),
           Attribute_Name => Name_Unchecked_Access);

      Lock_Stmt := Make_Procedure_Call_Statement (Loc,
        Name => Lock_Name,
        Parameter_Associations => New_List (Object_Parm));

      if Abort_Allowed then
         Stmts := New_List (
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Abort_Defer), Loc),
             Parameter_Associations => Empty_List),
           Lock_Stmt);

      else
         Stmts := New_List (Lock_Stmt);
      end if;

      if not Exc_Safe then
         Append (Unprot_Call, Stmts);
      else
         if Nkind (Op_Spec) = N_Function_Specification then
            Pre_Stmts := Stmts;
            Stmts     := Empty_List;
         else
            Append (Unprot_Call, Stmts);
         end if;

         if Service_Name /= Empty then
            Service_Stmt := Make_Procedure_Call_Statement (Loc,
              Name => Service_Name,
              Parameter_Associations =>
                New_List (New_Copy_Tree (Object_Parm)));
            Append (Service_Stmt, Stmts);
         end if;

         Unlock_Stmt :=
           Make_Procedure_Call_Statement (Loc,
             Name => Unlock_Name,
             Parameter_Associations => New_List (
               New_Copy_Tree (Object_Parm)));
         Append (Unlock_Stmt, Stmts);

         if Abort_Allowed then
            Append (
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc),
                Parameter_Associations => Empty_List),
              Stmts);
         end if;

         if Nkind (Op_Spec) = N_Function_Specification then
            Append (Return_Stmt, Stmts);
            Append (Make_Block_Statement (Loc,
              Declarations => New_List (Unprot_Call),
              Handled_Statement_Sequence =>
                Make_Handled_Sequence_Of_Statements (Loc,
                  Statements => Stmts)), Pre_Stmts);
            Stmts := Pre_Stmts;
         end if;
      end if;

      Sub_Body :=
        Make_Subprogram_Body (Loc,
          Declarations => Empty_List,
          Specification => P_Op_Spec,
          Handled_Statement_Sequence =>
            Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts));

      if not Exc_Safe then
         Set_Is_Protected_Subprogram_Body (Sub_Body);
      end if;

      return Sub_Body;
   end Build_Protected_Subprogram_Body;

   -------------------------------------
   -- Build_Protected_Subprogram_Call --
   -------------------------------------

   procedure Build_Protected_Subprogram_Call
     (N        : Node_Id;
      Name     : Node_Id;
      Rec      : Node_Id;
      External : Boolean := True)
   is
      Loc     : constant Source_Ptr := Sloc (N);
      Sub     : Entity_Id := Entity (Name);
      New_Sub : Node_Id;
      Params  : List_Id;

   begin
      if External then
         New_Sub := New_Occurrence_Of (External_Subprogram (Sub), Loc);
      else
         New_Sub :=
           New_Occurrence_Of (Protected_Body_Subprogram (Sub), Loc);
      end if;

      if Present (Parameter_Associations (N)) then
         Params := New_Copy_List_Tree (Parameter_Associations (N));
      else
         Params := New_List;
      end if;

      Prepend (Rec, Params);

      if Ekind (Sub) = E_Procedure then
         Rewrite (N,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Sub,
             Parameter_Associations => Params));

      else
         pragma Assert (Ekind (Sub) = E_Function);
         Rewrite (N,
           Make_Function_Call (Loc,
             Name => New_Sub,
             Parameter_Associations => Params));
      end if;

      if External
        and then Nkind (Rec) = N_Unchecked_Type_Conversion
        and then Is_Entity_Name (Expression (Rec))
        and then Is_Shared_Passive (Entity (Expression (Rec)))
      then
         Add_Shared_Var_Lock_Procs (N);
      end if;

   end Build_Protected_Subprogram_Call;

   -------------------------
   -- Build_Selected_Name --
   -------------------------

   function Build_Selected_Name
     (Prefix, Selector : Name_Id;
      Append_Char      : Character := ' ')
      return             Name_Id
   is
      Select_Buffer : String (1 .. Hostparm.Max_Name_Length);
      Select_Len    : Natural;

   begin
      Get_Name_String (Selector);
      Select_Len := Name_Len;
      Select_Buffer (1 .. Select_Len) := Name_Buffer (1 .. Name_Len);
      Get_Name_String (Prefix);

      --  If scope is anonymous type, discard suffix to recover name of
      --  single protected object. Otherwise use protected type name.

      if Name_Buffer (Name_Len) = 'T' then
         Name_Len := Name_Len - 1;
      end if;

      Name_Buffer (Name_Len + 1) := 'P';
      Name_Buffer (Name_Len + 2) := 'T';
      Name_Buffer (Name_Len + 3) := '_';
      Name_Buffer (Name_Len + 4) := '_';

      Name_Len := Name_Len + 4;
      for J in 1 .. Select_Len loop
         Name_Len := Name_Len + 1;
         Name_Buffer (Name_Len) := Select_Buffer (J);
      end loop;

      if Append_Char /= ' ' then
         Name_Len := Name_Len + 1;
         Name_Buffer (Name_Len) := Append_Char;
      end if;

      return Name_Find;
   end Build_Selected_Name;

   -----------------------------
   -- Build_Simple_Entry_Call --
   -----------------------------

   --  A task entry call is converted to a call to Call_Simple

   --    declare
   --       P : parms := (parm, parm, parm);
   --    begin
   --       Call_Simple (acceptor-task, entry-index, P'Address);
   --       parm := P.param;
   --       parm := P.param;
   --       ...
   --    end;

   --  Here Pnn is an aggregate of the type constructed for the entry to hold
   --  the parameters, and the constructed aggregate value contains either the
   --  parameters or, in the case of non-elementary types, references to these
   --  parameters. Then the address of this aggregate is passed to the runtime
   --  routine, along with the task id value and the task entry index value.
   --  Pnn is only required if parameters are present.

   --  The assignments after the call are present only in the case of in-out
   --  or out parameters for elementary types, and are used to assign back the
   --  resulting values of such parameters.

   --  Note: the reason that we insert a block here is that in the context
   --  of selects, conditional entry calls etc. the entry call statement
   --  appears on its own, not as an element of a list.

   --  A protected entry call is converted to a Protected_Entry_Call:

   --  declare
   --     P   : E1_Params := (param, param, param);
   --     Pnn : Boolean;
   --     Bnn : Communications_Block;

   --  declare
   --     P   : E1_Params := (param, param, param);
   --     Bnn : Communications_Block;

   --  begin
   --     Protected_Entry_Call (
   --       Object => po._object'Access,
   --       E => <entry index>;
   --       Uninterpreted_Data => P'Address;
   --       Mode => Simple_Call;
   --       Block => Bnn);
   --     parm := P.param;
   --     parm := P.param;
   --       ...
   --  end;

   procedure Build_Simple_Entry_Call
     (N       : Node_Id;
      Concval : Node_Id;
      Ename   : Node_Id;
      Index   : Node_Id)
   is
   begin
      Expand_Call (N);

      --  Convert entry call to Call_Simple call

      declare
         Loc       : constant Source_Ptr := Sloc (N);
         Parms     : constant List_Id    := Parameter_Associations (N);
         Pdecl     : Node_Id;
         Xdecl     : Node_Id;
         Decls     : List_Id;
         Conctyp   : Node_Id;
         Ent       : Entity_Id;
         Ent_Acc   : Entity_Id;
         P         : Entity_Id;
         X         : Entity_Id;
         Plist     : List_Id;
         Parm1     : Node_Id;
         Parm2     : Node_Id;
         Parm3     : Node_Id;
         Call      : Node_Id;
         Actual    : Node_Id;
         Formal    : Node_Id;
         N_Node    : Node_Id;
         N_Var     : Node_Id;
         Stats     : List_Id := New_List;
         Comm_Name : Entity_Id;

      begin
         --  Simple entry and entry family cases merge here

         Ent     := Entity (Ename);
         Ent_Acc := Entry_Parameters_Type (Ent);
         Conctyp := Etype (Concval);

         --  If prefix is an access type, dereference to obtain the task type

         if Is_Access_Type (Conctyp) then
            Conctyp := Designated_Type (Conctyp);
         end if;

         --  Special case for protected subprogram calls.

         if Is_Protected_Type (Conctyp)
           and then Is_Subprogram (Entity (Ename))
         then
            Build_Protected_Subprogram_Call
              (N, Ename, Convert_Concurrent (Concval, Conctyp));
            Analyze (N);
            return;
         end if;

         --  First parameter is the Task_Id value from the task value or the
         --  Object from the protected object value, obtained by selecting
         --  the _Task_Id or _Object from the result of doing an unchecked
         --  conversion to convert the value to the corresponding record type.

         Parm1 := Concurrent_Ref (Concval);

         --  Second parameter is the entry index, computed by the routine
         --  provided for this purpose. The value of this expression is
         --  assigned to an intermediate variable to assure that any entry
         --  family index expressions are evaluated before the entry
         --  parameters.

         if Abort_Allowed
           or else Restrictions (No_Entry_Queue) = False
           or else not Is_Protected_Type (Conctyp)
           or else Number_Entries (Conctyp) > 1
         then
            X := Make_Defining_Identifier (Loc, Name_uX);

            Xdecl :=
              Make_Object_Declaration (Loc,
                Defining_Identifier => X,
                Object_Definition =>
                  New_Reference_To (RTE (RE_Task_Entry_Index), Loc),
                Expression => Actual_Index_Expression (
                  Loc, Entity (Ename), Index, Concval));

            Decls := New_List (Xdecl);
            Parm2 := New_Reference_To (X, Loc);

         else
            Xdecl := Empty;
            Decls := New_List;
            Parm2 := Empty;
         end if;

         --  The third parameter is the packaged parameters. If there are
         --  none, then it is just the null address, since nothing is passed

         if No (Parms) then
            Parm3 := New_Reference_To (RTE (RE_Null_Address), Loc);
            P := Empty;

         --  Case of parameters present, where third argument is the address
         --  of a packaged record containing the required parameter values.

         else
            --  First build a list of parameter values, which are
            --  references to objects of the parameter types.

            Plist := New_List;

            Actual := First_Actual (N);
            Formal := First_Formal (Ent);

            while Present (Actual) loop

               --  If it is a by_copy_type, copy it to a new variable. The
               --  packaged record has a field that points to this variable.

               if Is_By_Copy_Type (Etype (Actual)) then
                  N_Node :=
                    Make_Object_Declaration (Loc,
                      Defining_Identifier =>
                        Make_Defining_Identifier (Loc,
                          Chars => New_Internal_Name ('I')),
                      Aliased_Present => True,
                      Object_Definition =>
                        New_Reference_To (Etype (Formal), Loc));

                  --  We have to make an assignment statement separate for
                  --  the case of limited type. We can not assign it unless
                  --  the Assignment_OK flag is set first.

                  if Ekind (Formal) /= E_Out_Parameter then
                     N_Var :=
                       New_Reference_To (Defining_Identifier (N_Node), Loc);
                     Set_Assignment_OK (N_Var);
                     Append_To (Stats,
                       Make_Assignment_Statement (Loc,
                         Name => N_Var,
                         Expression => Relocate_Node (Actual)));
                  end if;

                  Append (N_Node, Decls);

                  Append_To (Plist,
                    Make_Attribute_Reference (Loc,
                      Attribute_Name => Name_Unchecked_Access,
                    Prefix =>
                      New_Reference_To (Defining_Identifier (N_Node), Loc)));
               else
                  Append_To (Plist,
                    Make_Reference (Loc, Prefix => Relocate_Node (Actual)));
               end if;

               Next_Actual (Actual);
               Next_Formal_With_Extras (Formal);
            end loop;

            --  Now build the declaration of parameters initialized with the
            --  aggregate containing this constructed parameter list.

            P := Make_Defining_Identifier (Loc, Name_uP);

            Pdecl :=
              Make_Object_Declaration (Loc,
                Defining_Identifier => P,
                Object_Definition =>
                  New_Reference_To (Designated_Type (Ent_Acc), Loc),
                Expression =>
                  Make_Aggregate (Loc, Expressions => Plist));

            Parm3 :=
              Make_Attribute_Reference (Loc,
                Attribute_Name => Name_Address,
                Prefix => New_Reference_To (P, Loc));

            Append (Pdecl, Decls);
         end if;

         --  Now we can create the call, case of protected type

         if Is_Protected_Type (Conctyp) then
            if Abort_Allowed
              or else Restrictions (No_Entry_Queue) = False
              or else Number_Entries (Conctyp) > 1
            then
               --  Change the type of the index declaration

               Set_Object_Definition (Xdecl,
                 New_Reference_To (RTE (RE_Protected_Entry_Index), Loc));

               --  Some additional declarations for protected entry calls

               if No (Decls) then
                  Decls := New_List;
               end if;

               --  Bnn : Communications_Block;

               Comm_Name :=
                 Make_Defining_Identifier (Loc, New_Internal_Name ('B'));

               Append_To (Decls,
                 Make_Object_Declaration (Loc,
                   Defining_Identifier => Comm_Name,
                   Object_Definition =>
                     New_Reference_To (RTE (RE_Communication_Block), Loc)));

               --  Some additional statements for protected entry calls

               --     Protected_Entry_Call (
               --       Object => po._object'Access,
               --       E => <entry index>;
               --       Uninterpreted_Data => P'Address;
               --       Mode => Simple_Call;
               --       Block => Bnn);

               Call :=
                 Make_Procedure_Call_Statement (Loc,
                   Name =>
                     New_Reference_To (RTE (RE_Protected_Entry_Call), Loc),

                   Parameter_Associations => New_List (
                     Make_Attribute_Reference (Loc,
                       Attribute_Name => Name_Unchecked_Access,
                       Prefix         => Parm1),
                     Parm2,
                     Parm3,
                     New_Reference_To (RTE (RE_Simple_Call), Loc),
                     New_Occurrence_Of (Comm_Name, Loc)));

            else
               --     Protected_Single_Entry_Call (
               --       Object => po._object'Access,
               --       Uninterpreted_Data => P'Address;
               --       Mode => Simple_Call);

               Call :=
                 Make_Procedure_Call_Statement (Loc,
                   Name => New_Reference_To (
                     RTE (RE_Protected_Single_Entry_Call), Loc),

                   Parameter_Associations => New_List (
                     Make_Attribute_Reference (Loc,
                       Attribute_Name => Name_Unchecked_Access,
                       Prefix         => Parm1),
                     Parm3,
                     New_Reference_To (RTE (RE_Simple_Call), Loc)));
            end if;

         --  Case of task type

         else
            Call :=
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (RTE (RE_Call_Simple), Loc),
                Parameter_Associations => New_List (Parm1, Parm2, Parm3));

         end if;

         Append_To (Stats, Call);

         --  If there are out or in/out parameters by copy
         --  add assignment statements for the result values.

         if Present (Parms) then
            Actual := First_Actual (N);
            Formal := First_Formal (Ent);

            Set_Assignment_OK (Actual);
            while Present (Actual) loop
               if Is_By_Copy_Type (Etype (Actual))
                 and then Ekind (Formal) /= E_In_Parameter
               then
                  N_Node :=
                    Make_Assignment_Statement (Loc,
                      Name => New_Copy (Actual),
                      Expression =>
                        Make_Explicit_Dereference (Loc,
                          Make_Selected_Component (Loc,
                            Prefix => New_Reference_To (P, Loc),
                            Selector_Name =>
                              Make_Identifier (Loc, Chars (Formal)))));

                  --  In all cases (including limited private types) we
                  --  want the assignment to be valid.

                  Set_Assignment_OK (Name (N_Node));

                  --  If the call is the triggering alternative in an
                  --  asynchronous select, or the entry_call alternative
                  --  of a conditional entry call, the assignments for in-out
                  --  parameters are incorporated into the statement list
                  --  that follows, so that there are executed only if the
                  --  entry call succeeds.

                  if (Nkind (Parent (N)) = N_Triggering_Alternative
                       and then N = Triggering_Statement (Parent (N)))
                    or else
                     (Nkind (Parent (N)) = N_Entry_Call_Alternative
                       and then N = Entry_Call_Statement (Parent (N)))
                  then
                     if No (Statements (Parent (N))) then
                        Set_Statements (Parent (N), New_List);
                     end if;

                     Prepend (N_Node, Statements (Parent (N)));

                  else
                     Insert_After (Call, N_Node);
                  end if;
               end if;

               Next_Actual (Actual);
               Next_Formal_With_Extras (Formal);
            end loop;
         end if;

         --  Finally, create block and analyze it

         Rewrite (N,
           Make_Block_Statement (Loc,
             Declarations => Decls,
             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc,
                 Statements => Stats)));

         Analyze (N);
      end;

   end Build_Simple_Entry_Call;

   --------------------------------
   -- Build_Task_Activation_Call --
   --------------------------------

   procedure Build_Task_Activation_Call (N : Node_Id) is
      Loc        : constant Source_Ptr := Sloc (N);
      Chain      : Entity_Id;
      Call       : Node_Id;
      Name       : Node_Id;
      P          : Node_Id;

   begin
      --  Get the activation chain entity. Except in the case of a package
      --  body, this is in the node that was passed. For a package body, we
      --  have to find the corresponding package declaration node.

      if Nkind (N) = N_Package_Body then
         P := Corresponding_Spec (N);

         loop
            P := Parent (P);
            exit when Nkind (P) = N_Package_Declaration;
         end loop;

         Chain := Activation_Chain_Entity (P);

      else
         Chain := Activation_Chain_Entity (N);
      end if;

      if Present (Chain) then
         if Restricted_Profile then
            Name := New_Reference_To (RTE (RE_Activate_Restricted_Tasks), Loc);
         else
            Name := New_Reference_To (RTE (RE_Activate_Tasks), Loc);
         end if;

         Call :=
           Make_Procedure_Call_Statement (Loc,
             Name => Name,
             Parameter_Associations =>
               New_List (Make_Attribute_Reference (Loc,
                 Prefix => New_Occurrence_Of (Chain, Loc),
                 Attribute_Name => Name_Unchecked_Access)));

         if Nkind (N) = N_Package_Declaration then
            if Present (Corresponding_Body (N)) then
               null;

            elsif Present (Private_Declarations (Specification (N))) then
               Append (Call, Private_Declarations (Specification (N)));

            else
               Append (Call, Visible_Declarations (Specification (N)));
            end if;

         else
            if Present (Handled_Statement_Sequence (N)) then

               --  The call goes at the start of the statement sequence, but
               --  after the start of exception range label if one is present.

               declare
                  Stm : Node_Id;

               begin
                  Stm := First (Statements (Handled_Statement_Sequence (N)));

                  if Nkind (Stm) = N_Label and then Exception_Junk (Stm) then
                     Next (Stm);
                  end if;

                  Insert_Before (Stm, Call);
               end;

            else
               Set_Handled_Statement_Sequence (N,
                  Make_Handled_Sequence_Of_Statements (Loc,
                     Statements => New_List (Call)));
            end if;
         end if;

         Analyze (Call);
         Check_Task_Activation (N);
      end if;

   end Build_Task_Activation_Call;

   -------------------------------
   -- Build_Task_Allocate_Block --
   -------------------------------

   procedure Build_Task_Allocate_Block
     (Actions : List_Id;
      N       : Node_Id;
      Args    : List_Id)
   is
      T    : constant Entity_Id  := Entity (Expression (N));
      Init : constant Entity_Id  := Base_Init_Proc (T);
      Loc  : constant Source_Ptr := Sloc (N);

      Chain  : Entity_Id := Make_Defining_Identifier (Loc, Name_uChain);
      Blkent : Entity_Id;
      Block  : Node_Id;

   begin
      Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));

      Block :=
        Make_Block_Statement (Loc,
          Identifier => New_Reference_To (Blkent, Loc),
          Declarations => New_List (

            --  _Chain  : Activation_Chain;

            Make_Object_Declaration (Loc,
              Defining_Identifier => Chain,
              Aliased_Present => True,
              Object_Definition   =>
                New_Reference_To (RTE (RE_Activation_Chain), Loc))),

          Handled_Statement_Sequence =>
            Make_Handled_Sequence_Of_Statements (Loc,

              Statements => New_List (

               --  Init (Args);

                Make_Procedure_Call_Statement (Loc,
                  Name => New_Reference_To (Init, Loc),
                  Parameter_Associations => Args),

               --  Activate_Tasks (_Chain);

                Make_Procedure_Call_Statement (Loc,
                  Name => New_Reference_To (RTE (RE_Activate_Tasks), Loc),
                  Parameter_Associations => New_List (
                    Make_Attribute_Reference (Loc,
                      Prefix => New_Reference_To (Chain, Loc),
                      Attribute_Name => Name_Unchecked_Access))))),

          Has_Created_Identifier => True,
          Is_Task_Allocation_Block => True);

      Append_To (Actions,
        Make_Implicit_Label_Declaration (Loc,
          Defining_Identifier => Blkent,
          Label_Construct     => Block));

      Append_To (Actions, Block);

      Set_Activation_Chain_Entity (Block, Chain);

   end Build_Task_Allocate_Block;

   -----------------------------------
   -- Build_Task_Proc_Specification --
   -----------------------------------

   function Build_Task_Proc_Specification (T : Entity_Id) return Node_Id is
      Loc  : constant Source_Ptr := Sloc (T);
      Nam  : constant Name_Id    := Chars (T);
      Tdec : constant Node_Id    := Declaration_Node (T);
      Ent  : Entity_Id;

   begin
      Ent :=
        Make_Defining_Identifier (Loc,
          Chars => New_External_Name (Nam, 'B'));
      Set_Is_Internal (Ent);

      --  Associate the procedure with the task, if this is the declaration
      --  (and not the body) of the procedure.

      if No (Task_Body_Procedure (Tdec)) then
         Set_Task_Body_Procedure (Tdec, Ent);
      end if;

      return
        Make_Procedure_Specification (Loc,
          Defining_Unit_Name       => Ent,
          Parameter_Specifications =>
            New_List (
              Make_Parameter_Specification (Loc,
                Defining_Identifier =>
                  Make_Defining_Identifier (Loc, Name_uTask),
                Parameter_Type =>
                  Make_Access_Definition (Loc,
                    Subtype_Mark =>
                      New_Reference_To
                        (Corresponding_Record_Type (T), Loc)))));

   end Build_Task_Proc_Specification;

   ---------------------------------------
   -- Build_Unprotected_Subprogram_Body --
   ---------------------------------------

   function Build_Unprotected_Subprogram_Body
     (N    : Node_Id;
      Pid  : Node_Id)
      return Node_Id
   is
      Loc       : constant Source_Ptr := Sloc (N);
      Sub_Name  : Name_Id;
      N_Op_Spec : Node_Id;
      Op_Decls  : List_Id;

   begin
      --  Make an unprotected version of the subprogram for use
      --  within the same object, with a new name and an additional
      --  parameter representing the object.

      Op_Decls := Declarations (N);
      Sub_Name := Chars (Defining_Unit_Name (Specification (N)));

      N_Op_Spec :=
        Build_Protected_Sub_Specification
          (N, Pid, Unprotected => True);

      return
        Make_Subprogram_Body (Loc,
          Specification => N_Op_Spec,
          Declarations => Op_Decls,
          Handled_Statement_Sequence =>
            Handled_Statement_Sequence (N));

   end Build_Unprotected_Subprogram_Body;

   ----------------------------
   -- Collect_Entry_Families --
   ----------------------------

   procedure Collect_Entry_Families
     (Loc          : Source_Ptr;
      Cdecls       : List_Id;
      Current_Node : in out Node_Id;
      Conctyp      : Entity_Id)
   is
      Efam      : Entity_Id;
      Efam_Decl : Node_Id;
      Efam_Type : Entity_Id;

   begin
      Efam := First_Entity (Conctyp);

      while Present (Efam) loop

         if Ekind (Efam) = E_Entry_Family then
            Efam_Type :=
              Make_Defining_Identifier (Loc,
                Chars => New_Internal_Name ('F'));

            Efam_Decl :=
              Make_Full_Type_Declaration (Loc,
                Defining_Identifier => Efam_Type,
                Type_Definition =>
                  Make_Unconstrained_Array_Definition (Loc,
                    Subtype_Marks => (New_List (
                      New_Occurrence_Of (
                       Base_Type
                         (Etype (Discrete_Subtype_Definition
                           (Parent (Efam)))), Loc))),

                    Subtype_Indication =>
                      New_Reference_To (Standard_Character, Loc)));

            Insert_After (Current_Node, Efam_Decl);
            Current_Node := Efam_Decl;
            Analyze (Efam_Decl);

            Append_To (Cdecls,
              Make_Component_Declaration (Loc,
                Defining_Identifier =>
                  Make_Defining_Identifier (Loc, Chars (Efam)),

                Subtype_Indication =>
                  Make_Subtype_Indication (Loc,
                    Subtype_Mark =>
                      New_Occurrence_Of (Efam_Type, Loc),

                    Constraint  =>
                      Make_Index_Or_Discriminant_Constraint (Loc,
                        Constraints => New_List (
                          New_Occurrence_Of
                            (Etype (Discrete_Subtype_Definition
                              (Parent (Efam))), Loc))))));
         end if;

         Next_Entity (Efam);
      end loop;
   end Collect_Entry_Families;

   --------------------
   -- Concurrent_Ref --
   --------------------

   --  The expression returned for a reference to a concurrent
   --  object has the form:

   --    taskV!(name)._Task_Id

   --  for a task, and

   --    objectV!(name)._Object

   --  for a protected object.

   --  For the case of an access to a concurrent object,
   --  there is an extra explicit dereference:

   --    taskV!(name.all)._Task_Id
   --    objectV!(name.all)._Object

   --  here taskV and objectV are the types for the associated records, which
   --  contain the required _Task_Id and _Object fields for tasks and
   --  protected objects, respectively.

   --  For the case of a task type name, the expression is

   --    Self;

   --  i.e. a call to the Self function which returns precisely this Task_Id

   --  For the case of a protected type name, the expression is

   --    objectR

   --  which is a renaming of the _object field of the current object
   --  object record, passed into protected operations as a parameter.

   function Concurrent_Ref (N : Node_Id) return Node_Id is
      Loc  : constant Source_Ptr := Sloc (N);
      Ntyp : constant Entity_Id  := Etype (N);
      Dtyp : Entity_Id;
      Sel  : Name_Id;

      function Is_Current_Task (T : Entity_Id) return Boolean;
      --  Check whether the reference is to the immediately enclosing task
      --  type, or to an outer one (rare but legal).

      ---------------------
      -- Is_Current_Task --
      ---------------------

      function Is_Current_Task (T : Entity_Id) return Boolean is
         Scop : Entity_Id;

      begin
         Scop := Current_Scope;
         while Present (Scop)
           and then Scop /= Standard_Standard
         loop

            if Scop = T then
               return True;

            elsif Is_Task_Type (Scop) then
               return False;

            --  If this is a procedure nested within the task type, we must
            --  assume that it can be called from an inner task, and therefore
            --  cannot treat it as a local reference.

            elsif Is_Overloadable (Scop)
              and then In_Open_Scopes (T)
            then
               return False;

            else
               Scop := Scope (Scop);
            end if;
         end loop;

         --  We know that we are within the task body, so should have
         --  found it in scope.

         raise Program_Error;
      end Is_Current_Task;

   --  Start of processing for Concurrent_Ref

   begin
      if Is_Access_Type (Ntyp) then
         Dtyp := Designated_Type (Ntyp);

         if Is_Protected_Type (Dtyp) then
            Sel := Name_uObject;
         else
            Sel := Name_uTask_Id;
         end if;

         return
           Make_Selected_Component (Loc,
             Prefix =>
               Unchecked_Convert_To (Corresponding_Record_Type (Dtyp),
                 Make_Explicit_Dereference (Loc, N)),
             Selector_Name => Make_Identifier (Loc, Sel));

      elsif Is_Entity_Name (N)
        and then Is_Concurrent_Type (Entity (N))
      then
         if Is_Task_Type (Entity (N)) then

            if Is_Current_Task (Entity (N)) then
               return
                 Make_Function_Call (Loc,
                   Name => New_Reference_To (RTE (RE_Self), Loc));

            else
               declare
                  Decl   : Node_Id;
                  T_Self : constant Entity_Id
                    := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
                  T_Body : constant Node_Id
                    := Parent (Corresponding_Body (Parent (Entity (N))));

               begin
                  Decl := Make_Object_Declaration (Loc,
                     Defining_Identifier => T_Self,
                     Object_Definition =>
                       New_Occurrence_Of (RTE (RO_ST_Task_ID), Loc),
                     Expression =>
                       Make_Function_Call (Loc,
                         Name => New_Reference_To (RTE (RE_Self), Loc)));
                  Prepend (Decl, Declarations (T_Body));
                  Analyze (Decl);
                  Set_Scope (T_Self, Entity (N));
                  return New_Occurrence_Of (T_Self,  Loc);
               end;
            end if;

         else
            pragma Assert (Is_Protected_Type (Entity (N)));
            return
              New_Reference_To (
                Object_Ref (Corresponding_Body (Parent (Base_Type (Ntyp)))),
                Loc);
         end if;

      else
         pragma Assert (Is_Concurrent_Type (Ntyp));

         if Is_Protected_Type (Ntyp) then
            Sel := Name_uObject;
         else
            Sel := Name_uTask_Id;
         end if;

         return
           Make_Selected_Component (Loc,
             Prefix =>
               Unchecked_Convert_To (Corresponding_Record_Type (Ntyp),
                 New_Copy_Tree (N)),
             Selector_Name => Make_Identifier (Loc, Sel));
      end if;
   end Concurrent_Ref;

   ------------------------
   -- Convert_Concurrent --
   ------------------------

   function Convert_Concurrent
     (N    : Node_Id;
      Typ  : Entity_Id)
      return Node_Id
   is
   begin
      if not Is_Concurrent_Type (Typ) then
         return N;
      else
         return
           Unchecked_Convert_To (Corresponding_Record_Type (Typ),
             New_Copy_Tree (N));
      end if;
   end Convert_Concurrent;

   ----------------------------
   -- Entry_Index_Expression --
   ----------------------------

   function Entry_Index_Expression
     (Sloc  : Source_Ptr;
      Ent   : Entity_Id;
      Index : Node_Id;
      Ttyp  : Entity_Id)
      return  Node_Id
   is
      Expr : Node_Id;
      Num  : Node_Id;
      Lo   : Node_Id;
      Hi   : Node_Id;
      Prev : Entity_Id;
      S    : Node_Id;

   begin
      --  The queues of entries and entry families appear in  textual
      --  order in the associated record. The entry index is computed as
      --  the sum of the number of queues for all entries that precede the
      --  designated one, to which is added the index expression, if this
      --  expression denotes a member of a family.

      --  The following is a place holder for the count of simple entries.

      Num := Make_Integer_Literal (Sloc, 1);

      --  We construct an expression which is a series of addition
      --  operations. The first operand is the number of single entries that
      --  precede this one, the second operand is the index value relative
      --  to the start of the referenced family, and the remaining operands
      --  are the lengths of the entry families that precede this entry, i.e.
      --  the constructed expression is:

      --    number_simple_entries +
      --      (s'pos (index-value) - s'pos (family'first)) + 1 +
      --      family'length + ...

      --  where index-value is the given index value, and s is the index
      --  subtype (we have to use pos because the subtype might be an
      --  enumeration type preventing direct subtraction).
      --  Note that the task entry array is one-indexed.

      --  The upper bound of the entry family may be a discriminant, so we
      --  retrieve the lower bound explicitly to compute offset, rather than
      --  using the index subtype which may mention a discriminant.

      if Present (Index) then
         S := Etype (Discrete_Subtype_Definition (Declaration_Node (Ent)));

         Expr :=
           Make_Op_Add (Sloc,
             Left_Opnd  => Num,

             Right_Opnd =>
               Family_Offset (
                 Sloc,
                 Make_Attribute_Reference (Sloc,
                   Attribute_Name => Name_Pos,
                   Prefix => New_Reference_To (Base_Type (S), Sloc),
                   Expressions => New_List (Relocate_Node (Index))),
                 Type_Low_Bound (S),
                 Ttyp));
      else
         Expr := Num;
      end if;

      --  Now add lengths of preceding entries and entry families.

      Prev := First_Entity (Ttyp);

      while Chars (Prev) /= Chars (Ent)
        or else (Ekind (Prev) /= Ekind (Ent))
        or else not Sem_Ch6.Type_Conformant (Ent, Prev)
      loop
         if Ekind (Prev) = E_Entry then
            Set_Intval (Num, Intval (Num) + 1);

         elsif Ekind (Prev) = E_Entry_Family then
            S :=
              Etype (Discrete_Subtype_Definition (Declaration_Node (Prev)));
            Lo := Type_Low_Bound  (S);
            Hi := Type_High_Bound (S);

            Expr :=
              Make_Op_Add (Sloc,
              Left_Opnd  => Expr,
              Right_Opnd => Family_Size (Sloc, Hi, Lo, Ttyp));

         --  Other components are anonymous types to be ignored.

         else
            null;
         end if;

         Next_Entity (Prev);
      end loop;

      return Expr;
   end Entry_Index_Expression;

   ---------------------------
   -- Establish_Task_Master --
   ---------------------------

   procedure Establish_Task_Master (N : Node_Id) is
      Call : Node_Id;

   begin
      if Restrictions (No_Task_Hierarchy) = False then
         Call := Build_Runtime_Call (Sloc (N), RE_Enter_Master);
         Prepend_To (Declarations (N), Call);
         Analyze (Call);
      end if;
   end Establish_Task_Master;

   --------------------------------
   -- Expand_Accept_Declarations --
   --------------------------------

   --  Part of the expansion of an accept statement involves the creation of
   --  a declaration that can be referenced from the statement sequence of
   --  the accept:

   --    Ann : Address;

   --  This declaration is inserted immediately before the accept statement
   --  and it is important that it be inserted before the statements of the
   --  statement sequence are analyzed. Thus it would be too late to create
   --  this declaration in the Expand_N_Accept_Statement routine, which is
   --  why there is a separate procedure to be called directly from Sem_Ch9.

   --  Ann is used to hold the address of the record containing the parameters
   --  (see Expand_N_Entry_Call for more details on how this record is built).
   --  References to the parameters do an unchecked conversion of this address
   --  to a pointer to the required record type, and then access the field that
   --  holds the value of the required parameter. The entity for the address
   --  variable is held as the top stack element (i.e. the last element) of the
   --  Accept_Address stack in the corresponding entry entity, and this element
   --  must be set in place  before the statements are processed.

   --  The above description applies to the case of a stand alone accept
   --  statement, i.e. one not appearing as part of a select alternative.

   --  For the case of an accept that appears as part of a select alternative
   --  of a selective accept, we must still create the declaration right away,
   --  since Ann is needed immediately, but there is an important difference:

   --    The declaration is inserted before the selective accept, not before
   --    the accept statement (which is not part of a list anyway, and so would
   --    not accommodate inserted declarations)

   --    We only need one address variable for the entire selective accept. So
   --    the Ann declaration is created only for the first accept alternative,
   --    and subsequent accept alternatives reference the same Ann variable.

   --  We can distinguish the two cases by seeing whether the accept statement
   --  is part of a list. If not, then it must be in an accept alternative.

   --  To expand the requeue statement, a label is provided at the end of
   --  the accept statement or alternative of which it is a part, so that
   --  the statement can be skipped after the requeue is complete.
   --  This label is created here rather than during the expansion of the
   --  accept statement, because it will be needed by any requeue
   --  statements within the accept, which are expanded before the
   --  accept.

   procedure Expand_Accept_Declarations (N : Node_Id; Ent : Entity_Id) is
      Loc    : constant Source_Ptr := Sloc (N);
      Ann    : Entity_Id := Empty;
      Adecl  : Node_Id;
      Lab_Id : Node_Id;
      Lab    : Node_Id;
      Ldecl  : Node_Id;
      Ldecl2 : Node_Id;

   begin
      if Expander_Active then

         --  If we have no handled statement sequence, then build a dummy
         --  sequence consisting of a null statement. This is only done if
         --  pragma FIFO_Within_Priorities is specified. The issue here is
         --  that even a null accept body has an effect on the called task
         --  in terms of its position in the queue, so we cannot optimize
         --  the context switch away. However, if FIFO_Within_Priorities
         --  is not active, the optimization is legitimate, since we can
         --  say that our dispatching policy (i.e. the default dispatching
         --  policy) reorders the queue to be the same as just before the
         --  call. In the absence of a specified dispatching policy, we are
         --  allowed to modify queue orders for a given priority at will!

         if Opt.Task_Dispatching_Policy = 'F' and then
           not Present (Handled_Statement_Sequence (N))
         then
            Set_Handled_Statement_Sequence (N,
              Make_Handled_Sequence_Of_Statements (Loc,
                New_List (Make_Null_Statement (Loc))));
         end if;

         --  Create and declare two labels to be placed at the end of the
         --  accept statement. The first label is used to allow requeues to
         --  skip the remainder of entry processing. The second label is
         --  used to skip the remainder of entry processing if the rendezvous
         --  completes in the middle of the accept body.

         if Present (Handled_Statement_Sequence (N)) then
            Lab_Id := Make_Identifier (Loc, New_Internal_Name ('L'));
            Set_Entity (Lab_Id,
              Make_Defining_Identifier (Loc, Chars (Lab_Id)));
            Lab := Make_Label (Loc, Lab_Id);
            Ldecl :=
              Make_Implicit_Label_Declaration (Loc,
                Defining_Identifier  => Entity (Lab_Id),
                Label_Construct      => Lab);
            Append (Lab, Statements (Handled_Statement_Sequence (N)));

            Lab_Id := Make_Identifier (Loc, New_Internal_Name ('L'));
            Set_Entity (Lab_Id,
              Make_Defining_Identifier (Loc, Chars (Lab_Id)));
            Lab := Make_Label (Loc, Lab_Id);
            Ldecl2 :=
              Make_Implicit_Label_Declaration (Loc,
                Defining_Identifier  => Entity (Lab_Id),
                Label_Construct      => Lab);
            Append (Lab, Statements (Handled_Statement_Sequence (N)));

         else
            Ldecl := Empty;
            Ldecl2 := Empty;
         end if;

         --  Case of stand alone accept statement

         if Is_List_Member (N) then

            if Present (Handled_Statement_Sequence (N)) then
               Ann :=
                 Make_Defining_Identifier (Loc,
                   Chars => New_Internal_Name ('A'));

               Adecl :=
                 Make_Object_Declaration (Loc,
                   Defining_Identifier => Ann,
                   Object_Definition =>
                     New_Reference_To (RTE (RE_Address), Loc));

               Insert_Before (N, Adecl);
               Analyze (Adecl);

               Insert_Before (N, Ldecl);
               Analyze (Ldecl);

               Insert_Before (N, Ldecl2);
               Analyze (Ldecl2);
            end if;

         --  Case of accept statement which is in an accept alternative

         else
            declare
               Acc_Alt : constant Node_Id := Parent (N);
               Sel_Acc : constant Node_Id := Parent (Acc_Alt);
               Alt     : Node_Id;

            begin
               pragma Assert (Nkind (Acc_Alt) = N_Accept_Alternative);
               pragma Assert (Nkind (Sel_Acc) = N_Selective_Accept);

               --  ??? Consider a single label for select statements.

               if Present (Handled_Statement_Sequence (N)) then
                  Prepend (Ldecl2,
                     Statements (Handled_Statement_Sequence (N)));
                  Analyze (Ldecl2);

                  Prepend (Ldecl,
                     Statements (Handled_Statement_Sequence (N)));
                  Analyze (Ldecl);
               end if;

               --  Find first accept alternative of the selective accept. A
               --  valid selective accept must have at least one accept in it.

               Alt := First (Select_Alternatives (Sel_Acc));

               while Nkind (Alt) /= N_Accept_Alternative loop
                  Next (Alt);
               end loop;

               --  If we are the first accept statement, then we have to
               --  create the Ann variable, as for the stand alone case,
               --  except that it is inserted before the selective accept.
               --  Similarly, a label for requeue expansion must be
               --  declared.

               if N = Accept_Statement (Alt) then
                  Ann :=
                    Make_Defining_Identifier (Loc, New_Internal_Name ('A'));

                  Adecl :=
                    Make_Object_Declaration (Loc,
                      Defining_Identifier => Ann,
                      Object_Definition =>
                        New_Reference_To (RTE (RE_Address), Loc));

                  Insert_Before (Sel_Acc, Adecl);
                  Analyze (Adecl);

               --  If we are not the first accept statement, then find the
               --  Ann variable allocated by the first accept and use it.

               else
                  Ann :=
                    Node (Last_Elmt (Accept_Address
                      (Entity (Entry_Direct_Name (Accept_Statement (Alt))))));
               end if;
            end;
         end if;

         --  Merge here with Ann either created or referenced, and Adecl
         --  pointing to the corresponding declaration. Remaining processing
         --  is the same for the two cases.

         if Present (Ann) then
            Append_Elmt (Ann, Accept_Address (Ent));
         end if;
      end if;
   end Expand_Accept_Declarations;

   ---------------------------------------------
   -- Expand_Access_Protected_Subprogram_Type --
   ---------------------------------------------

   procedure Expand_Access_Protected_Subprogram_Type (N : Node_Id) is
      Loc    : constant Source_Ptr := Sloc (N);
      Comps  : List_Id;
      T      : constant Entity_Id  := Defining_Identifier (N);
      D_T    : constant Entity_Id  := Designated_Type (T);
      D_T2   : constant Entity_Id  := Make_Defining_Identifier
                                        (Loc, New_Internal_Name ('D'));
      E_T    : constant Entity_Id  := Make_Defining_Identifier
                                        (Loc, New_Internal_Name ('E'));
      P_List : constant List_Id    := Build_Protected_Spec
                                        (N, RTE (RE_Address), False, D_T);
      Decl1  : Node_Id;
      Decl2  : Node_Id;
      Def1   : Node_Id;

   begin
      --  Create access to protected subprogram with full signature.

      if Nkind (Type_Definition (N)) = N_Access_Function_Definition then
         Def1 :=
           Make_Access_Function_Definition (Loc,
             Parameter_Specifications => P_List,
             Subtype_Mark => New_Copy (Subtype_Mark (Type_Definition (N))));

      else
         Def1 :=
           Make_Access_Procedure_Definition (Loc,
             Parameter_Specifications => P_List);
      end if;

      Decl1 :=
        Make_Full_Type_Declaration (Loc,
          Defining_Identifier => D_T2,
          Type_Definition => Def1);

      Insert_After (N, Decl1);

      --  Create Equivalent_Type, a record with two components for an
      --  an access to object an an access to subprogram.

      Comps := New_List (
        Make_Component_Declaration (Loc,
          Defining_Identifier =>
            Make_Defining_Identifier (Loc, New_Internal_Name ('P')),
          Subtype_Indication  =>
            New_Occurrence_Of (RTE (RE_Address), Loc)),

        Make_Component_Declaration (Loc,
          Defining_Identifier =>
            Make_Defining_Identifier (Loc, New_Internal_Name ('S')),
          Subtype_Indication  =>
            New_Occurrence_Of (D_T2, Loc)));

      Decl2 :=
        Make_Full_Type_Declaration (Loc,
          Defining_Identifier => E_T,
          Type_Definition     =>
            Make_Record_Definition (Loc,
              Component_List =>
                Make_Component_List (Loc,
                  Component_Items => Comps)));

      Insert_After (Decl1, Decl2);
      Set_Equivalent_Type (T, E_T);

   end Expand_Access_Protected_Subprogram_Type;

   --------------------------
   -- Expand_Entry_Barrier --
   --------------------------

   procedure Expand_Entry_Barrier (N : Node_Id; Ent : Entity_Id) is
      Loc       : constant Source_Ptr := Sloc (N);
      Func      : Node_Id;
      B_F       : Node_Id;
      Prot      : constant Entity_Id  := Scope (Ent);
      Spec_Decl : Node_Id := Parent (Prot);
      Body_Decl : Node_Id;
      Cond      : Node_Id := Condition (Entry_Body_Formal_Part (N));

   begin
      --  The body of the entry barrier must be analyzed in the context of
      --  the protected object, but its scope is external to it, just as any
      --  other unprotected version of a protected operation. The specification
      --  has been produced when the protected type declaration was elaborated.
      --  We build the body, insert it in the enclosing scope, but analyze it
      --  in the current context. A more uniform approach would be to treat a
      --  barrier just as a protected function, and discard the protected
      --  version of it because it is never called.

      if Expander_Active then
         B_F := Build_Barrier_Function (N, Ent, Prot);
         Func := Barrier_Function (Ent);
         Set_Corresponding_Spec (B_F, Func);

         Body_Decl := Parent (Corresponding_Body (Spec_Decl));

         if Nkind (Parent (Body_Decl)) = N_Subunit then
            Body_Decl := Corresponding_Stub (Parent (Body_Decl));
         end if;

         Insert_Before_And_Analyze (Body_Decl, B_F);

         Update_Prival_Subtypes (B_F);

         Set_Privals (Spec_Decl, N, Loc);
         Set_Discriminals (Spec_Decl);
         Set_Scope (Func, Scope (Prot));
      else
         Analyze (Cond);
      end if;

      --  The Ravenscar profile restricts barriers to simple variables
      --  declared within the protected object. We also allow Boolean
      --  constants, since these appear in several published examples
      --  and are also allowed by the Aonix compiler.

      --  Note that after analysis variables in this context will be
      --  replaced by the corresponding prival, that is to say a renaming
      --  of a selected component of the form _Object.Var. If expansion is
      --  disabled, as within a generic, we check that the entity appears in
      --  the current scope.

      if Is_Entity_Name (Cond) then

         if Entity (Cond) = Standard_False
              or else
            Entity (Cond) = Standard_True
         then
            return;

         elsif not Expander_Active
           and then Scope (Entity (Cond)) = Current_Scope
         then
            return;

         elsif Present (Renamed_Object (Entity (Cond)))
           and then
             Nkind (Renamed_Object (Entity (Cond))) = N_Selected_Component
           and then
             Chars (Prefix (Renamed_Object (Entity (Cond)))) = Name_uObject
         then
            return;
         end if;
      end if;

      --  It is not a boolean variable or literal, so check the restriction

      Check_Restriction (Boolean_Entry_Barriers, Cond);
   end Expand_Entry_Barrier;

   ------------------------------------
   -- Expand_Entry_Body_Declarations --
   ------------------------------------

   procedure Expand_Entry_Body_Declarations (N : Node_Id) is
      Loc        : constant Source_Ptr := Sloc (N);
      Index_Spec : Node_Id;

   begin
      if Expander_Active then

         --  Expand entry bodies corresponding to entry families
         --  by assigning a placeholder for the constant that will
         --  be used to expand references to the entry index parameter.

         Index_Spec :=
           Entry_Index_Specification (Entry_Body_Formal_Part (N));

         if Present (Index_Spec) then
            Set_Entry_Index_Constant (
              Defining_Identifier (Index_Spec),
              Make_Defining_Identifier (Loc, New_Internal_Name ('I')));
         end if;

      end if;
   end Expand_Entry_Body_Declarations;

   ------------------------------
   -- Expand_N_Abort_Statement --
   ------------------------------

   --  Expand abort T1, T2, .. Tn; into:
   --    Abort_Tasks (Task_List'(1 => T1.Task_Id, 2 => T2.Task_Id ...))

   procedure Expand_N_Abort_Statement (N : Node_Id) is
      Loc    : constant Source_Ptr := Sloc (N);
      Tlist  : constant List_Id    := Names (N);
      Count  : Nat;
      Aggr   : Node_Id;
      Tasknm : Node_Id;

   begin
      Aggr := Make_Aggregate (Loc, Component_Associations => New_List);
      Count := 0;

      Tasknm := First (Tlist);

      while Present (Tasknm) loop
         Count := Count + 1;
         Append_To (Component_Associations (Aggr),
           Make_Component_Association (Loc,
             Choices => New_List (
               Make_Integer_Literal (Loc, Count)),
             Expression => Concurrent_Ref (Tasknm)));
         Next (Tasknm);
      end loop;

      Rewrite (N,
        Make_Procedure_Call_Statement (Loc,
          Name => New_Reference_To (RTE (RE_Abort_Tasks), Loc),
          Parameter_Associations => New_List (
            Make_Qualified_Expression (Loc,
              Subtype_Mark => New_Reference_To (RTE (RE_Task_List), Loc),
              Expression => Aggr))));

      Analyze (N);

   end Expand_N_Abort_Statement;

   -------------------------------
   -- Expand_N_Accept_Statement --
   -------------------------------

   --  This procedure handles expansion of accept statements that stand
   --  alone, i.e. they are not part of an accept alternative. The expansion
   --  of accept statement in accept alternatives is handled by the routines
   --  Expand_N_Accept_Alternative and Expand_N_Selective_Accept. The
   --  following description applies only to stand alone accept statements.

   --  If there is no handled statement sequence, or only null statements,
   --  then this is called a trivial accept, and the expansion is:

   --    Accept_Trivial (entry-index)

   --  If there is a handled statement sequence, then the expansion is:

   --    Ann : Address;
   --    {Lnn : Label}

   --    begin
   --       begin
   --          Accept_Call (entry-index, Ann);
   --          <statement sequence from N_Accept_Statement node>
   --          Complete_Rendezvous;
   --          <<Lnn>>
   --
   --       exception
   --          when ... =>
   --             <exception handler from N_Accept_Statement node>
   --             Complete_Rendezvous;
   --          when ... =>
   --             <exception handler from N_Accept_Statement node>
   --             Complete_Rendezvous;
   --          ...
   --       end;

   --    exception
   --       when all others =>
   --          Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
   --    end;

   --  The first three declarations were already inserted ahead of the
   --  accept statement by the Expand_Accept_Declarations procedure, which
   --  was called directly from the semantics during analysis of the accept.
   --  statement, before analyzing its contained statements.

   --  The declarations from the N_Accept_Statement, as noted in Sinfo, come
   --  from possible expansion activity (the original source of course does
   --  not have any declarations associated with the accept statement, since
   --  an accept statement has no declarative part). In particular, if the
   --  expander is active, the first such declaration is the declaration of
   --  the Accept_Params_Ptr entity (see Sem_Ch9.Analyze_Accept_Statement).
   --
   --  The two blocks are merged into a single block if the inner block has
   --  no exception handlers, but otherwise two blocks are required, since
   --  exceptions might be raised in the exception handlers of the inner
   --  block, and Exceptional_Complete_Rendezvous must be called.

   procedure Expand_N_Accept_Statement (N : Node_Id) is
      Loc     : constant Source_Ptr := Sloc (N);
      Stats   : constant Node_Id    := Handled_Statement_Sequence (N);
      Ename   : constant Node_Id    := Entry_Direct_Name (N);
      Eindx   : constant Node_Id    := Entry_Index (N);
      Eent    : constant Entity_Id  := Entity (Ename);
      Acstack : constant Elist_Id   := Accept_Address (Eent);
      Ann     : constant Entity_Id  := Node (Last_Elmt (Acstack));
      Ttyp    : constant Entity_Id  := Etype (Scope (Eent));
      Call    : Node_Id;
      Block   : Node_Id;

      function Null_Statements (Stats : List_Id) return Boolean;
      --  Check for null statement sequence (i.e a list of labels and
      --  null statements)

      function Null_Statements (Stats : List_Id) return Boolean is
         Stmt : Node_Id;

      begin
         Stmt := First (Stats);
         while Nkind (Stmt) /= N_Empty
           and then (Nkind (Stmt) = N_Null_Statement
                       or else
                     Nkind (Stmt) = N_Label)
         loop
            Next (Stmt);
         end loop;

         return Nkind (Stmt) = N_Empty;
      end Null_Statements;

   --  Start of processing for Expand_N_Accept_Statement

   begin
      --  If accept statement is not part of a list, then its parent must be
      --  an accept alternative, and, as described above, we do not do any
      --  expansion for such accept statements at this level.

      if not Is_List_Member (N) then
         pragma Assert (Nkind (Parent (N)) = N_Accept_Alternative);
         return;

      --  Trivial accept case (no statement sequence, or null statements).
      --  If the accept statement has declarations, then just insert them
      --  before the procedure call.

      --  We avoid this optimization when FIFO_Within_Priorities is active,
      --  since it is not correct according to annex D semantics. The problem
      --  is that the call is required to reorder the acceptors position on
      --  its ready queue, even though there is nothing to be done. However,
      --  if no policy is specified, then we decide that our dispatching
      --  policy always reorders the queue right after the RV to look the
      --  way they were just before the RV. Since we are allowed to freely
      --  reorder same-priority queues (this is part of what dispatching
      --  policies are all about), the optimization is legitimate.

      elsif Opt.Task_Dispatching_Policy /= 'F'
        and then (No (Stats) or else Null_Statements (Statements (Stats)))
      then
         if Present (Declarations (N)) then
            Insert_Actions (N, Declarations (N));
         end if;

         Rewrite (N,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Accept_Trivial), Loc),
             Parameter_Associations => New_List (
               Entry_Index_Expression (Loc, Entity (Ename), Eindx, Ttyp))));

         Analyze (N);

         --  Discard Entry_Address that was created for it, so it will not be
         --  emitted if this accept statement is in the statement part of a
         --  delay alternative.

         if Present (Stats) then
            Remove_Last_Elmt (Acstack);
         end if;

      --  Case of statement sequence present

      else
         --  Construct the block, using the declarations from the accept
         --  statement if any to initialize the declarations of the block.

         Block :=
           Make_Block_Statement (Loc,
             Declarations               => Declarations (N),
             Handled_Statement_Sequence => Build_Accept_Body (N));

         --  Prepend call to Accept_Call to main statement sequence

         Call :=
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Accept_Call), Loc),
             Parameter_Associations => New_List (
               Entry_Index_Expression (Loc, Entity (Ename), Eindx, Ttyp),
               New_Reference_To (Ann, Loc)));

         Prepend (Call, Statements (Stats));
         Analyze (Call);

         --  Replace the accept statement by the new block

         Rewrite (N, Block);
         Analyze (N);

         --  Last step is to unstack the Accept_Address value

         Remove_Last_Elmt (Acstack);
      end if;

   end Expand_N_Accept_Statement;

   ----------------------------------
   -- Expand_N_Asynchronous_Select --
   ----------------------------------

   --  This procedure assumes that the trigger statement is an entry
   --  call. A delay alternative should already have been expanded
   --  into an entry call to the appropriate delay object Wait entry.

   --  If the trigger is a task entry call, the select is implemented
   --  with Task_Entry_Call:

   --    declare
   --       B : Boolean;
   --       C : Boolean;
   --       P : parms := (parm, parm, parm);
   --
   --        --  Clean is added by Exp_Ch7.Expand_Cleanup_Actions.
   --
   --       procedure _clean is
   --       begin
   --          ...
   --          Cancel_Task_Entry_Call (C);
   --          ...
   --       end _clean;
   --    begin
   --       Abort_Defer;
   --       Task_Entry_Call
   --         (acceptor-task,
   --          entry-index,
   --          P'Address,
   --          Asynchronous_Call,
   --          B);
   --       begin
   --          begin
   --             Abort_Undefer;
   --             abortable-part
   --          at end
   --             _clean;        --  Added by Exp_Ch7.Expand_Cleanup_Actions.
   --          end;
   --       exception
   --       when Abort_Signal => Abort_Undefer;
   --       end;
   --       parm := P.param;
   --       parm := P.param;
   --       ...
   --       if not C then
   --          triggered-statements
   --       end if;
   --    end;

   --  Note that Build_Simple_Entry_Call is used to expand the entry
   --  of the asynchronous entry call (by the
   --  Expand_N_Entry_Call_Statement procedure) as follows:

   --    declare
   --       P : parms := (parm, parm, parm);
   --    begin
   --       Call_Simple (acceptor-task, entry-index, P'Address);
   --       parm := P.param;
   --       parm := P.param;
   --       ...
   --    end;

   --  so the task at hand is to convert the latter expansion into the former

   --  If the trigger is a protected entry call, the select is
   --  implemented with Protected_Entry_Call:

   --  declare
   --     P   : E1_Params := (param, param, param);
   --     Bnn : Communications_Block;
   --  begin
   --     declare
   --
   --        --  Clean is added by Exp_Ch7.Expand_Cleanup_Actions.
   --
   --        procedure _clean is
   --        begin
   --           ...
   --           if Enqueued (Bnn) then
   --              Cancel_Protected_Entry_Call (Bnn);
   --           end if;
   --           ...
   --        end _clean;
   --     begin
   --        begin
   --           Protected_Entry_Call (
   --             Object => po._object'Access,
   --             E => <entry index>;
   --             Uninterpreted_Data => P'Address;
   --             Mode => Asynchronous_Call;
   --             Block => Bnn);
   --           if Enqueued (Bnn) then
   --              <abortable part>
   --           end if;
   --        at end
   --           _clean;        --  Added by Exp_Ch7.Expand_Cleanup_Actions.
   --        end;
   --     exception
   --     when Abort_Signal =>
   --        Abort_Undefer;
   --        null;
   --     end;
   --     if not Cancelled (Bnn) then
   --        triggered statements
   --     end if;
   --  end;

   --  Build_Simple_Entry_Call is used to expand the all to a simple
   --  protected entry call:

   --  declare
   --     P   : E1_Params := (param, param, param);
   --     Bnn : Communications_Block;

   --  begin
   --     Protected_Entry_Call (
   --       Object => po._object'Access,
   --       E => <entry index>;
   --       Uninterpreted_Data => P'Address;
   --       Mode => Simple_Call;
   --       Block => Bnn);
   --     parm := P.param;
   --     parm := P.param;
   --       ...
   --  end;

   --  The job is to convert this to the asynchronous form.

   --  If the trigger is a delay statement, it will have been expanded
   --  into a call to one of the GNARL delay procedures. This routine
   --  will convert this into a protected entry call on a delay object
   --  and then continue processing as for a protected entry call trigger.
   --  This requires declaring a Delay_Block object and adding a pointer
   --  to this object to the parameter list of the delay procedure to form
   --  the parameter list of the entry call. This object is used by
   --  the runtime to queue the delay request.

   --  For a description of the use of P and the assignments after the
   --  call, see Expand_N_Entry_Call_Statement.

   procedure Expand_N_Asynchronous_Select (N : Node_Id) is
      Loc    : constant Source_Ptr := Sloc (N);
      Trig   : constant Node_Id    := Triggering_Alternative (N);
      Abrt   : constant Node_Id    := Abortable_Part (N);
      Tstats : constant List_Id    := Statements (Trig);

      Ecall           : Node_Id;
      Astats          : List_Id := Statements (Abrt);
      Concval         : Node_Id;
      Ename           : Node_Id;
      Index           : Node_Id;
      Hdle            : List_Id;
      Decls           : List_Id;
      Decl            : Node_Id;
      Parms           : List_Id;
      Parm            : Node_Id;
      Call            : Node_Id;
      Stmts           : List_Id;
      Enqueue_Call    : Node_Id;
      Stmt            : Node_Id;
      B               : Entity_Id;
      Pdef            : Entity_Id;
      Dblock_Ent      : Entity_Id;
      N_Orig          : Node_Id;
      Abortable_Block : Node_Id;
      Cancel_Param    : Entity_Id;
      Blkent          : Entity_Id;
      Target_Undefer  : RE_Id;
      Undefer_Args    : List_Id := No_List;

   begin
      Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
      Ecall := Triggering_Statement (Trig);

      --  The arguments in the call may require dynamic allocation, and the
      --  call statement may have been transformed into a block. The block
      --  may contain additional declarations for internal entities, and the
      --  original call is found by sequential search.

      if Nkind (Ecall) = N_Block_Statement then
         Ecall := First (Statements (Handled_Statement_Sequence (Ecall)));

         while Nkind (Ecall) /= N_Procedure_Call_Statement
           and then Nkind (Ecall) /= N_Entry_Call_Statement
         loop
            Next (Ecall);
         end loop;
      end if;

      --  If a delay was used as a trigger, it will have been expanded
      --  into a procedure call. Convert it to the appropriate sequence of
      --  statements, similar to what is done for a task entry call.
      --  Note that this currently supports only Duration, Real_Time.Time,
      --  and Calendar.Time.

      if Nkind (Ecall) = N_Procedure_Call_Statement then

         --  Add a Delay_Block object to the parameter list of the
         --  delay procedure to form the parameter list of the Wait
         --  entry call.

         Dblock_Ent := Make_Defining_Identifier (Loc, New_Internal_Name ('D'));

         Pdef := Entity (Name (Ecall));

         if Is_RTE (Pdef, RO_CA_Delay_For) then
            Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_Duration), Loc);

         elsif Is_RTE (Pdef, RO_CA_Delay_Until) then
            Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_Calendar), Loc);

         else pragma Assert (Is_RTE (Pdef, RO_RT_Delay_Until));
            Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_RT), Loc);
         end if;

         Append_To (Parameter_Associations (Ecall),
           Make_Attribute_Reference (Loc,
             Prefix => New_Reference_To (Dblock_Ent, Loc),
             Attribute_Name => Name_Unchecked_Access));

         --  Create the inner block to protect the abortable part.

         Hdle := New_List (
           Make_Exception_Handler (Loc,
             Exception_Choices =>
               New_List (New_Reference_To (Stand.Abort_Signal, Loc)),
             Statements => New_List (
               Make_Procedure_Call_Statement (Loc,
                 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)))));

         Prepend_To (Astats,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)));

         Abortable_Block :=
           Make_Block_Statement (Loc,
             Identifier => New_Reference_To (Blkent, Loc),
             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc,
                 Statements => Astats),
             Has_Created_Identifier => True,
             Is_Asynchronous_Call_Block => True);

         --  Append call to if Enqueue (When, DB'Unchecked_Access) then

         Rewrite (Ecall,
           Make_Implicit_If_Statement (N,
             Condition => Make_Function_Call (Loc,
               Name => Enqueue_Call,
               Parameter_Associations => Parameter_Associations (Ecall)),
             Then_Statements =>
               New_List (Make_Block_Statement (Loc,
                 Handled_Statement_Sequence =>
                   Make_Handled_Sequence_Of_Statements (Loc,
                     Statements => New_List (
                       Make_Implicit_Label_Declaration (Loc,
                         Defining_Identifier => Blkent,
                         Label_Construct     => Abortable_Block),
                       Abortable_Block),
                     Exception_Handlers => Hdle)))));

         Stmts := New_List (Ecall);

         --  Construct statement sequence for new block

         Append_To (Stmts,
           Make_Implicit_If_Statement (N,
             Condition => Make_Function_Call (Loc,
               Name => New_Reference_To (
                 RTE (RE_Timed_Out), Loc),
               Parameter_Associations => New_List (
                 Make_Attribute_Reference (Loc,
                   Prefix => New_Reference_To (Dblock_Ent, Loc),
                   Attribute_Name => Name_Unchecked_Access))),
             Then_Statements => Tstats));

         --  The result is the new block

         Set_Entry_Cancel_Parameter (Blkent, Dblock_Ent);

         Rewrite (N,
           Make_Block_Statement (Loc,
             Declarations => New_List (
               Make_Object_Declaration (Loc,
                 Defining_Identifier => Dblock_Ent,
                 Aliased_Present => True,
                 Object_Definition => New_Reference_To (
                   RTE (RE_Delay_Block), Loc))),

             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc, Stmts)));

         Analyze (N);
         return;

      else
         N_Orig := N;
      end if;

      Extract_Entry (Ecall, Concval, Ename, Index);
      Build_Simple_Entry_Call (Ecall, Concval, Ename, Index);

      Stmts := Statements (Handled_Statement_Sequence (Ecall));
      Decls := Declarations (Ecall);

      if Is_Protected_Type (Etype (Concval)) then

         --  Get the declarations of the block expanded from the entry call

         Decl := First (Decls);
         while Present (Decl)
           and then (Nkind (Decl) /= N_Object_Declaration
             or else not Is_RTE
               (Etype (Object_Definition (Decl)), RE_Communication_Block))
         loop
            Next (Decl);
         end loop;

         pragma Assert (Present (Decl));
         Cancel_Param := Defining_Identifier (Decl);

         --  Change the mode of the Protected_Entry_Call call.
         --  Protected_Entry_Call (
         --    Object => po._object'Access,
         --    E => <entry index>;
         --    Uninterpreted_Data => P'Address;
         --    Mode => Asynchronous_Call;
         --    Block => Bnn);

         Stmt := First (Stmts);

         --  Skip assignments to temporaries created for in-out parameters.
         --  This makes unwarranted assumptions about the shape of the expanded
         --  tree for the call, and should be cleaned up ???

         while Nkind (Stmt) /= N_Procedure_Call_Statement loop
            Next (Stmt);
         end loop;

         Call := Stmt;

         Parm := First (Parameter_Associations (Call));
         while Present (Parm)
           and then not Is_RTE (Etype (Parm), RE_Call_Modes)
         loop
            Next (Parm);
         end loop;

         pragma Assert (Present (Parm));
         Rewrite (Parm, New_Reference_To (RTE (RE_Asynchronous_Call), Loc));
         Analyze (Parm);

         --  Append an if statement to execute the abortable part.
         --  if Enqueued (Bnn) then

         Append_To (Stmts,
           Make_Implicit_If_Statement (N,
             Condition => Make_Function_Call (Loc,
               Name => New_Reference_To (
                 RTE (RE_Enqueued), Loc),
               Parameter_Associations => New_List (
                 New_Reference_To (Cancel_Param, Loc))),
             Then_Statements => Astats));

         Abortable_Block :=
           Make_Block_Statement (Loc,
             Identifier => New_Reference_To (Blkent, Loc),
             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc,
                 Statements => Stmts),
             Has_Created_Identifier => True,
             Is_Asynchronous_Call_Block => True);

         --  For the JVM call Update_Exception instead of Abort_Undefer.
         --  See 4jexcept.ads for an explanation.

         if Hostparm.Java_VM then
            Target_Undefer := RE_Update_Exception;
            Undefer_Args :=
              New_List (Make_Function_Call (Loc,
                          Name => New_Occurrence_Of
                                    (RTE (RE_Current_Target_Exception), Loc)));
         else
            Target_Undefer := RE_Abort_Undefer;
         end if;

         Stmts := New_List (
           Make_Block_Statement (Loc,
             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc,
                 Statements => New_List (
                   Make_Implicit_Label_Declaration (Loc,
                     Defining_Identifier => Blkent,
                     Label_Construct     => Abortable_Block),
                   Abortable_Block),

               --  exception

                 Exception_Handlers => New_List (
                   Make_Exception_Handler (Loc,

               --  when Abort_Signal =>
               --     Abort_Undefer.all;

                     Exception_Choices =>
                       New_List (New_Reference_To (Stand.Abort_Signal, Loc)),
                     Statements => New_List (
                       Make_Procedure_Call_Statement (Loc,
                         Name => New_Reference_To (
                           RTE (Target_Undefer), Loc),
                         Parameter_Associations => Undefer_Args)))))),

         --  if not Cancelled (Bnn) then
         --     triggered statements
         --  end if;

           Make_Implicit_If_Statement (N,
             Condition => Make_Op_Not (Loc,
               Right_Opnd =>
                 Make_Function_Call (Loc,
                   Name => New_Occurrence_Of (RTE (RE_Cancelled), Loc),
                   Parameter_Associations => New_List (
                     New_Occurrence_Of (Cancel_Param, Loc)))),
             Then_Statements => Tstats));

      --  Asynchronous task entry call

      else
         if No (Decls) then
            Decls := New_List;
         end if;

         B := Make_Defining_Identifier (Loc, Name_uB);

         --  Insert declaration of B in declarations of existing block

         Prepend_To (Decls,
           Make_Object_Declaration (Loc,
             Defining_Identifier => B,
             Object_Definition => New_Reference_To (Standard_Boolean, Loc)));

         Cancel_Param := Make_Defining_Identifier (Loc, Name_uC);

         --  Insert declaration of C in declarations of existing block

         Prepend_To (Decls,
           Make_Object_Declaration (Loc,
             Defining_Identifier => Cancel_Param,
             Object_Definition => New_Reference_To (Standard_Boolean, Loc)));

         --  Remove and save the call to Call_Simple.

         Stmt := First (Stmts);

         --  Skip assignments to temporaries created for in-out parameters.
         --  This makes unwarranted assumptions about the shape of the expanded
         --  tree for the call, and should be cleaned up ???

         while Nkind (Stmt) /= N_Procedure_Call_Statement loop
            Next (Stmt);
         end loop;

         Call := Stmt;

         --  Create the inner block to protect the abortable part.

         Hdle :=  New_List (
           Make_Exception_Handler (Loc,
             Exception_Choices =>
               New_List (New_Reference_To (Stand.Abort_Signal, Loc)),
             Statements => New_List (
               Make_Procedure_Call_Statement (Loc,
                 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)))));

         Prepend_To (Astats,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)));

         Abortable_Block :=
           Make_Block_Statement (Loc,
             Identifier => New_Reference_To (Blkent, Loc),
             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc,
                 Statements => Astats),
             Has_Created_Identifier => True,
             Is_Asynchronous_Call_Block => True);

         Insert_After (Call,
           Make_Block_Statement (Loc,
             Handled_Statement_Sequence =>
               Make_Handled_Sequence_Of_Statements (Loc,
                 Statements => New_List (
                   Make_Implicit_Label_Declaration (Loc,
                     Defining_Identifier => Blkent,
                     Label_Construct     => Abortable_Block),
                   Abortable_Block),
                 Exception_Handlers => Hdle)));

         --  Create new call statement

         Parms := Parameter_Associations (Call);
         Append_To (Parms, New_Reference_To (RTE (RE_Asynchronous_Call), Loc));
         Append_To (Parms, New_Reference_To (B, Loc));
         Rewrite (Call,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Task_Entry_Call), Loc),
             Parameter_Associations => Parms));

         --  Construct statement sequence for new block

         Append_To (Stmts,
           Make_Implicit_If_Statement (N,
             Condition => Make_Op_Not (Loc,
               New_Reference_To (Cancel_Param, Loc)),
             Then_Statements => Tstats));

         --  Protected the call against abortion

         Prepend_To (Stmts,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Abort_Defer), Loc),
             Parameter_Associations => Empty_List));
      end if;

      Set_Entry_Cancel_Parameter (Blkent, Cancel_Param);

      --  The result is the new block

      Rewrite (N_Orig,
        Make_Block_Statement (Loc,
          Declarations => Decls,
          Handled_Statement_Sequence =>
            Make_Handled_Sequence_Of_Statements (Loc, Stmts)));

      Analyze (N_Orig);

   end Expand_N_Asynchronous_Select;

   -------------------------------------
   -- Expand_N_Conditional_Entry_Call --
   -------------------------------------

   --  The conditional task entry call is converted to a call to
   --  Task_Entry_Call:

   --    declare
   --       B : Boolean;
   --       P : parms := (parm, parm, parm);

   --    begin
   --       Task_Entry_Call
   --         (acceptor-task,
   --          entry-index,
   --          P'Address,
   --          Conditional_Call,
   --          B);
   --       parm := P.param;
   --       parm := P.param;
   --       ...
   --       if B then
   --          normal-statements
   --       else
   --          else-statements
   --       end if;
   --    end;

   --  For a description of the use of P and the assignments after the
   --  call, see Expand_N_Entry_Call_Statement. Note that the entry call
   --  of the conditional entry call has already been expanded (by the
   --  Expand_N_Entry_Call_Statement procedure) as follows:

   --    declare
   --       P : parms := (parm, parm, parm);
   --    begin
   --       ... info for in-out parameters
   --       Call_Simple (acceptor-task, entry-index, P'Address);
   --       parm := P.param;
   --       parm := P.param;
   --       ...
   --    end;

   --  so the task at hand is to convert the latter expansion into the former

   --  The conditional protected entry call is converted to a call to
   --  Protected_Entry_Call:

   --    declare
   --       P : parms := (parm, parm, parm);
   --       Bnn : Communications_Block;

   --    begin
   --       Protected_Entry_Call (
   --         Object => po._object'Access,
   --         E => <entry index>;
   --         Uninterpreted_Data => P'Address;
   --         Mode => Conditional_Call;
   --         Block => Bnn);
   --       parm := P.param;
   --       parm := P.param;
   --       ...
   --       if Cancelled (Bnn) then
   --          else-statements
   --       else
   --          normal-statements
   --       end if;
   --    end;

   --  As for tasks, the entry call of the conditional entry call has
   --  already been expanded (by the Expand_N_Entry_Call_Statement procedure)
   --  as follows:

   --    declare
   --       P   : E1_Params := (param, param, param);
   --       Bnn : Communications_Block;

   --    begin
   --       Protected_Entry_Call (
   --         Object => po._object'Access,
   --         E => <entry index>;
   --         Uninterpreted_Data => P'Address;
   --         Mode => Simple_Call;
   --         Block => Bnn);
   --       parm := P.param;
   --       parm := P.param;
   --         ...
   --    end;

   procedure Expand_N_Conditional_Entry_Call (N : Node_Id) is
      Loc : constant Source_Ptr := Sloc (N);
      Alt : constant Node_Id    := Entry_Call_Alternative (N);
      Blk : Node_Id             := Entry_Call_Statement (Alt);
      Transient_Blk : Node_Id;

      Parms   : List_Id;
      Parm    : Node_Id;
      Call    : Node_Id;
      Stmts   : List_Id;
      B       : Entity_Id;
      Decl    : Node_Id;
      Stmt    : Node_Id;

   begin
      --  As described above, The entry alternative is transformed into a
      --  block that contains the gnulli call, and possibly assignment
      --  statements for in-out parameters. The gnulli call may itself be
      --  rewritten into a transient block if some unconstrained parameters
      --  require it. We need to retrieve the call to complete its parameter
      --  list.

      Transient_Blk :=
         First_Real_Statement (Handled_Statement_Sequence (Blk));

      if Present (Transient_Blk)
        and then
        Nkind (Transient_Blk) =  N_Block_Statement
      then
         Blk := Transient_Blk;
      end if;

      Stmts := Statements (Handled_Statement_Sequence (Blk));

      Stmt := First (Stmts);

      while Nkind (Stmt) /= N_Procedure_Call_Statement loop
         Next (Stmt);
      end loop;

      Call := Stmt;

      Parms := Parameter_Associations (Call);

      if Is_RTE (Entity (Name (Call)), RE_Protected_Entry_Call) then

         --  Substitute Conditional_Entry_Call for Simple_Call
         --  parameter.

         Parm := First (Parms);
         while Present (Parm)
           and then not Is_RTE (Etype (Parm), RE_Call_Modes)
         loop
            Next (Parm);
         end loop;

         pragma Assert (Present (Parm));
         Rewrite (Parm, New_Reference_To (RTE (RE_Conditional_Call), Loc));

         Analyze (Parm);

         --  Find the Communication_Block parameter for the call
         --  to the Cancelled function.

         Decl := First (Declarations (Blk));
         while Present (Decl)
           and then not
             Is_RTE (Etype (Object_Definition (Decl)), RE_Communication_Block)
         loop
            Next (Decl);
         end loop;

         --  Add an if statement to execute the else part if the call
         --  does not succeed (as indicated by the Cancelled predicate).

         Append_To (Stmts,
           Make_Implicit_If_Statement (N,
             Condition => Make_Function_Call (Loc,
               Name => New_Reference_To (RTE (RE_Cancelled), Loc),
               Parameter_Associations => New_List (
                 New_Reference_To (Defining_Identifier (Decl), Loc))),
             Then_Statements => Else_Statements (N),
             Else_Statements => Statements (Alt)));

      else
         B := Make_Defining_Identifier (Loc, Name_uB);

         --  Insert declaration of B in declarations of existing block

         if No (Declarations (Blk)) then
            Set_Declarations (Blk, New_List);
         end if;

         Prepend_To (Declarations (Blk),
         Make_Object_Declaration (Loc,
           Defining_Identifier => B,
           Object_Definition => New_Reference_To (Standard_Boolean, Loc)));

         --  Create new call statement

         Append_To (Parms, New_Reference_To (RTE (RE_Conditional_Call), Loc));
         Append_To (Parms, New_Reference_To (B, Loc));

         Rewrite (Call,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Task_Entry_Call), Loc),
             Parameter_Associations => Parms));

         --  Construct statement sequence for new block

         Append_To (Stmts,
           Make_Implicit_If_Statement (N,
             Condition => New_Reference_To (B, Loc),
             Then_Statements => Statements (Alt),
             Else_Statements => Else_Statements (N)));

      end if;

      --  The result is the new block

      Rewrite (N,
        Make_Block_Statement (Loc,
          Declarations => Declarations (Blk),
          Handled_Statement_Sequence =>
            Make_Handled_Sequence_Of_Statements (Loc, Stmts)));

      Analyze (N);

   end Expand_N_Conditional_Entry_Call;

   ---------------------------------------
   -- Expand_N_Delay_Relative_Statement --
   ---------------------------------------

   --  Delay statement is implemented as a procedure call to Delay_For
   --  defined in Ada.Calendar.Delays in order to reduce the overhead of
   --  simple delays imposed by the use of Protected Objects.

   procedure Expand_N_Delay_Relative_Statement (N : Node_Id) is
      Loc : constant Source_Ptr := Sloc (N);

   begin
      Rewrite (N,
        Make_Procedure_Call_Statement (Loc,
          Name => New_Reference_To (RTE (RO_CA_Delay_For), Loc),
          Parameter_Associations => New_List (Expression (N))));
      Analyze (N);
   end Expand_N_Delay_Relative_Statement;

   ------------------------------------
   -- Expand_N_Delay_Until_Statement --
   ------------------------------------

   --  Delay Until statement is implemented as a procedure call to
   --  Delay_Until defined in Ada.Calendar.Delays and Ada.Real_Time.Delays.

   procedure Expand_N_Delay_Until_Statement (N : Node_Id) is
      Loc : constant Source_Ptr := Sloc (N);
      Typ : Entity_Id;

   begin
      if Is_RTE (Base_Type (Etype (Expression (N))), RO_CA_Time) then
         Typ := RTE (RO_CA_Delay_Until);
      else
         Typ := RTE (RO_RT_Delay_Until);
      end if;

      Rewrite (N,
        Make_Procedure_Call_Statement (Loc,
          Name => New_Reference_To (Typ, Loc),
          Parameter_Associations => New_List (Expression (N))));

      Analyze (N);
   end Expand_N_Delay_Until_Statement;

   -------------------------
   -- Expand_N_Entry_Body --
   -------------------------

   procedure Expand_N_Entry_Body (N : Node_Id) is
      Loc         : constant Source_Ptr := Sloc (N);
      Next_Op     : Node_Id;
      Dec         : Node_Id := Parent (Current_Scope);
      Ent_Formals : Node_Id := Entry_Body_Formal_Part (N);
      Index_Spec  : Node_Id := Entry_Index_Specification (Ent_Formals);

   begin
      --  Add the renamings for private declarations and discriminants.

      Add_Discriminal_Declarations
        (Declarations (N), Defining_Identifier (Dec), Name_uObject, Loc);
      Add_Private_Declarations
        (Declarations (N), Defining_Identifier (Dec), Name_uObject, Loc);

      if Present (Index_Spec) then
         Append_List_To (Declarations (N),
           Index_Constant_Declaration
             (N, Defining_Identifier (Index_Spec), Defining_Identifier (Dec)));
      end if;

      --  Associate privals and discriminals with the next protected
      --  operation body to be expanded. These are used to expand
      --  references to private data objects and discriminants,
      --  respectively.

      Next_Op := Next_Protected_Operation (N);

      if Present (Next_Op) then
         Set_Privals (Dec, Next_Op, Loc);
         Set_Discriminals (Dec);
      end if;

   end Expand_N_Entry_Body;

   -----------------------------------
   -- Expand_N_Entry_Call_Statement --
   -----------------------------------

   --  An entry call is expanded into GNARLI calls to implement
   --  a simple entry call (see Build_Simple_Entry_Call).

   procedure Expand_N_Entry_Call_Statement (N : Node_Id) is
      Concval : Node_Id;
      Ename   : Node_Id;
      Index   : Node_Id;

   begin
      --  If this entry call is part of an asynchronous select, don't
      --  expand it here; it will be expanded with the select statement.
      --  Don't expand timed entry calls either, as they are translated
      --  into asynchronous entry calls.

      --  ??? This whole approach is questionable; it may be better
      --  to go back to allowing the expansion to take place and then
      --  attempting to fix it up in Expand_N_Asynchronous_Select.
      --  The tricky part is figuring out whether the expanded
      --  call is on a task or protected entry.

      if (Nkind (Parent (N)) /= N_Triggering_Alternative
           or else N /= Triggering_Statement (Parent (N)))
        and then (Nkind (Parent (N)) /= N_Entry_Call_Alternative
                   or else N /= Entry_Call_Statement (Parent (N))
                   or else Nkind (Parent (Parent (N))) /= N_Timed_Entry_Call)
      then
         Extract_Entry (N, Concval, Ename, Index);
         Build_Simple_Entry_Call (N, Concval, Ename, Index);
      end if;

   end Expand_N_Entry_Call_Statement;

   --------------------------------
   -- Expand_N_Entry_Declaration --
   --------------------------------

   --  If there are parameters, then first, each of the formals is marked
   --  by setting Is_Entry_Formal. Next a record type is built which is
   --  used to hold the parameter values. The name of this record type is
   --  entryP where entry is the name of the entry, with an additional
   --  corresponding access type called entryPA. The record type has matching
   --  components for each formal (the component names are the same as the
   --  formal names). For elementary types, the component type matches the
   --  formal type. For composite types, an access type is declared (with
   --  the name formalA) which designates the formal type, and the type of
   --  the component is this access type. Finally the Entry_Component of
   --  each formal is set to reference the corresponding record component.

   procedure Expand_N_Entry_Declaration (N : Node_Id) is
      Loc        : constant Source_Ptr := Sloc (N);
      Entry_Ent  : constant Entity_Id  := Defining_Identifier (N);
      Components : List_Id;
      Formal     : Node_Id;
      Ftype      : Entity_Id;
      Last_Decl  : Node_Id;
      Component  : Entity_Id;
      Ctype      : Entity_Id;
      Decl       : Node_Id;
      Rec_Ent    : Entity_Id;
      Acc_Ent    : Entity_Id;

   begin
      Formal := First_Formal (Entry_Ent);
      Last_Decl := N;

      --  Most processing is done only if parameters are present

      if Present (Formal) then
         Components := New_List;

         --  Loop through formals

         while Present (Formal) loop
            Set_Is_Entry_Formal (Formal);
            Component :=
              Make_Defining_Identifier (Sloc (Formal), Chars (Formal));
            Set_Entry_Component (Formal, Component);
            Set_Entry_Formal (Component, Formal);
            Ftype := Etype (Formal);

            --  Declare new access type and then append

            Ctype :=
              Make_Defining_Identifier (Loc, New_Internal_Name ('A'));

            Decl :=
              Make_Full_Type_Declaration (Loc,
                Defining_Identifier => Ctype,
                Type_Definition     =>
                  Make_Access_To_Object_Definition (Loc,
                    All_Present        => True,
                    Constant_Present   => Ekind (Formal) = E_In_Parameter,
                    Subtype_Indication => New_Reference_To (Ftype, Loc)));

            Insert_After (Last_Decl, Decl);
            Last_Decl := Decl;

            Append_To (Components,
              Make_Component_Declaration (Loc,
                Defining_Identifier => Component,
                Subtype_Indication  => New_Reference_To (Ctype, Loc)));

            Next_Formal_With_Extras (Formal);
         end loop;

         --  Create the Entry_Parameter_Record declaration

         Rec_Ent :=
           Make_Defining_Identifier (Loc, New_Internal_Name ('P'));

         Decl :=
           Make_Full_Type_Declaration (Loc,
             Defining_Identifier => Rec_Ent,
             Type_Definition     =>
               Make_Record_Definition (Loc,
                 Component_List =>
                   Make_Component_List (Loc,
                     Component_Items => Components)));

         Insert_After (Last_Decl, Decl);
         Last_Decl := Decl;

         --  Construct and link in the corresponding access type

         Acc_Ent :=
           Make_Defining_Identifier (Loc, New_Internal_Name ('A'));

         Set_Entry_Parameters_Type (Entry_Ent, Acc_Ent);

         Decl :=
           Make_Full_Type_Declaration (Loc,
             Defining_Identifier => Acc_Ent,
             Type_Definition     =>
               Make_Access_To_Object_Definition (Loc,
                 All_Present        => True,
                 Subtype_Indication => New_Reference_To (Rec_Ent, Loc)));

         Insert_After (Last_Decl, Decl);
         Last_Decl := Decl;

      end if;

   end Expand_N_Entry_Declaration;

   -----------------------------
   -- Expand_N_Protected_Body --
   -----------------------------

   --  Protected bodies are expanded to the completion of the subprograms
   --  created for the corresponding protected type. These are a protected
   --  and unprotected version of each protected subprogram in the object,
   --  a function to calculate each entry barrier, and a procedure to
   --  execute the sequence of statements of each protected entry body.
   --  For example, for protected type ptype:

   --  function entB
   --    (O : System.Address;
   --     E : Protected_Entry_Index)
   --     return Boolean
   --  is
   --     <discriminant renamings>
   --     <private object renamings>
   --  begin
   --     return <barrier expression>;
   --  end entB;

   --  procedure pprocN (_object : in out poV;...) is
   --     <discriminant renamings>
   --     <private object renamings>
   --  begin
   --     <sequence of statements>
   --  end pprocN;

   --  procedure pproc (_object : in out poV;...) is
   --     procedure _clean is
   --       Pn : Boolean;
   --     begin
   --       ptypeS (_object, Pn);
   --       Unlock (_object._object'Access);
   --       Abort_Undefer.all;
   --     end _clean;
   --  begin
   --     Abort_Defer.all;
   --     Lock (_object._object'Access);
   --     pprocN (_object;...);
   --  at end
   --     _clean;
   --  end pproc;

   --  function pfuncN (_object : poV;...) return Return_Type is
   --     <discriminant renamings>
   --     <private object renamings>
   --  begin
   --     <sequence of statements>
   --  end pfuncN;

   --  function pfunc (_object : poV) return Return_Type is
   --     procedure _clean is
   --     begin
   --        Unlock (_object._object'Access);
   --        Abort_Undefer.all;
   --     end _clean;
   --  begin
   --     Abort_Defer.all;
   --     Lock (_object._object'Access);
   --     return pfuncN (_object);
   --  at end
   --     _clean;
   --  end pfunc;

   --  procedure entE
   --    (O : System.Address;
   --     P : System.Address;
   --     E : Protected_Entry_Index)
   --  is
   --     <discriminant renamings>
   --     <private object renamings>
   --     type poVP is access poV;
   --     _Object : ptVP := ptVP!(O);
   --  begin
   --     begin
   --        <statement sequence>
   --        Complete_Entry_Body (_Object._Object);
   --     exception
   --        when all others =>
   --           Exceptional_Complete_Entry_Body (
   --             _Object._Object, Get_GNAT_Exception);
   --     end;
   --  end entE;

   --  The type poV is the record created for the protected type to hold
   --  the state of the protected object.

   procedure Expand_N_Protected_Body (N : Node_Id) is
      Pid          : constant Entity_Id  := Corresponding_Spec (N);
      Has_Entries  : Boolean := False;
      Op_Decl      : Node_Id;
      Op_Body      : Node_Id;
      Op_Id        : Entity_Id;
      New_Op_Body  : Node_Id;
      Current_Node : Node_Id;
      Num_Entries  : Natural := 0;

   begin
      if Nkind (Parent (N)) = N_Subunit then

         --  This is the proper body corresponding to a stub. The declarations
         --  must be inserted at the point of the stub, which is in the decla-
         --  rative part of the parent unit.

         Current_Node := Corresponding_Stub (Parent (N));

      else
         Current_Node := N;
      end if;

      Op_Body := First (Declarations (N));

      --  The protected body is replaced with the bodies of its
      --  protected operations, and the declarations for internal objects
      --  that may have been created for entry family bounds.

      Rewrite (N, Make_Null_Statement (Sloc (N)));
      Analyze (N);

      while Present (Op_Body) loop

         case Nkind (Op_Body) is
            when N_Subprogram_Declaration =>
               null;

            when N_Subprogram_Body =>

               --  Exclude functions created to analyze defaults.

               if not Is_Eliminated (Defining_Entity (Op_Body)) then
                  New_Op_Body :=
                    Build_Unprotected_Subprogram_Body (Op_Body, Pid);

                  Insert_After (Current_Node, New_Op_Body);
                  Current_Node := New_Op_Body;
                  Analyze (New_Op_Body);

                  Update_Prival_Subtypes (New_Op_Body);

                  --  Build the corresponding protected operation only if
                  --  this is a visible operation of the type, or if it is
                  --  an interrupt handler. Otherwise it is only callable
                  --  from within the object, and the unprotected version
                  --  is sufficient.

                  if Present (Corresponding_Spec (Op_Body)) then
                     Op_Decl :=
                       Unit_Declaration_Node (Corresponding_Spec (Op_Body));

                     if Nkind (Parent (Op_Decl)) = N_Protected_Definition
                       and then
                         (List_Containing (Op_Decl) =
                                  Visible_Declarations (Parent (Op_Decl))
                           or else
                            Is_Interrupt_Handler
                              (Corresponding_Spec (Op_Body)))
                     then
                        New_Op_Body :=
                           Build_Protected_Subprogram_Body (
                             Op_Body, Pid, Specification (New_Op_Body));

                        Insert_After (Current_Node, New_Op_Body);
                        Analyze (New_Op_Body);
                     end if;
                  end if;
               end if;

            when N_Entry_Body =>
               Op_Id := Defining_Identifier (Op_Body);
               Has_Entries := True;
               Num_Entries := Num_Entries + 1;

               New_Op_Body := Build_Protected_Entry (Op_Body, Op_Id, Pid);

               Insert_After (Current_Node, New_Op_Body);
               Current_Node := New_Op_Body;
               Analyze (New_Op_Body);

               Update_Prival_Subtypes (New_Op_Body);

            when N_Implicit_Label_Declaration =>
               null;

            when N_Itype_Reference =>
               Insert_After (Current_Node, New_Copy (Op_Body));

            when N_Freeze_Entity =>
               New_Op_Body := New_Copy (Op_Body);

               if Present (Entity (Op_Body))
                 and then Freeze_Node (Entity (Op_Body)) = Op_Body
               then
                  Set_Freeze_Node (Entity (Op_Body), New_Op_Body);
               end if;

               Insert_After (Current_Node, New_Op_Body);
               Current_Node := New_Op_Body;
               Analyze (New_Op_Body);

            when N_Pragma =>
               New_Op_Body := New_Copy (Op_Body);
               Insert_After (Current_Node, New_Op_Body);
               Current_Node := New_Op_Body;
               Analyze (New_Op_Body);

            when N_Object_Declaration =>
               pragma Assert (not Comes_From_Source (Op_Body));
               New_Op_Body := New_Copy (Op_Body);
               Insert_After (Current_Node, New_Op_Body);
               Current_Node := New_Op_Body;
               Analyze (New_Op_Body);

            when others =>
               raise Program_Error;

         end case;

         Next (Op_Body);
      end loop;

      --  Finally, create the body of the function that maps an entry index
      --  into the corresponding body index, except when there is no entry,
      --  or in a ravenscar-like profile (no abort, no entry queue, 1 entry)

      if Has_Entries
        and then (Abort_Allowed
                    or else Restrictions (No_Entry_Queue) = False
                    or else Num_Entries > 1)
      then
         New_Op_Body := Build_Find_Body_Index (Pid);
         Insert_After (Current_Node, New_Op_Body);
         Analyze (New_Op_Body);
      end if;
   end Expand_N_Protected_Body;

   -----------------------------------------
   -- Expand_N_Protected_Type_Declaration --
   -----------------------------------------

   --  First we create a corresponding record type declaration used to
   --  represent values of this protected type.
   --  The general form of this type declaration is

   --    type poV (discriminants) is record
   --      _Object       : aliased <kind>Protection
   --         [(<entry count> [, <handler count>])];
   --      [entry_family  : array (bounds) of Void;]
   --      <private data fields>
   --    end record;

   --  The discriminants are present only if the corresponding protected
   --  type has discriminants, and they exactly mirror the protected type
   --  discriminants. The private data fields similarly mirror the
   --  private declarations of the protected type.

   --  The Object field is always present. It contains RTS specific data
   --  used to control the protected object. It is declared as Aliased
   --  so that it can be passed as a pointer to the RTS. This allows the
   --  protected record to be referenced within RTS data structures.
   --  An appropriate Protection type and discriminant are generated.

   --  The Service field is present for protected objects with entries. It
   --  contains sufficient information to allow the entry service procedure
   --  for this object to be called when the object is not known till runtime.

   --  One entry_family component is present for each entry family in the
   --  task definition (see Expand_N_Task_Type_Declaration).

   --  When a protected object is declared, an instance of the protected type
   --  value record is created. The elaboration of this declaration creates
   --  the correct bounds for the entry families, and also evaluates the
   --  priority expression if needed. The initialization routine for
   --  the protected type itself then calls Initialize_Protection with
   --  appropriate parameters to initialize the value of the Task_Id field.
   --  Install_Handlers may be also called if a pragma Attach_Handler applies.

   --  Note: this record is passed to the subprograms created by the
   --  expansion of protected subprograms and entries. It is an in parameter
   --  to protected functions and an in out parameter to procedures and
   --  entry bodies. The Entity_Id for this created record type is placed
   --  in the Corresponding_Record_Type field of the associated protected
   --  type entity.

   --  Next we create a procedure specifications for protected subprograms
   --  and entry bodies. For each protected subprograms two subprograms are
   --  created, an unprotected and a protected version. The unprotected
   --  version is called from within other operations of the same protected
   --  object.

   --  We also build the call to register the procedure if a pragma
   --  Interrupt_Handler applies.

   --  A single subprogram is created to service all entry bodies; it has an
   --  additional boolean out parameter indicating that the previous entry
   --  call made by the current task was serviced immediately, i.e. not by
   --  proxy. The O parameter contains a pointer to a record object of the
   --  type described above. An untyped interface is used here to allow this
   --  procedure to be called in places where the type of the object to be
   --  serviced is not known. This must be done, for example, when a call
   --  that may have been requeued is cancelled; the corresponding object
   --  must be serviced, but which object that is not known till runtime.

   --  procedure ptypeS
   --    (O : System.Address; P : out Boolean);
   --  procedure pprocN (_object : in out poV);
   --  procedure pproc (_object : in out poV);
   --  function pfuncN (_object : poV);
   --  function pfunc (_object : poV);
   --  ...

   --  Note that this must come after the record type declaration, since
   --  the specs refer to this type.

   procedure Expand_N_Protected_Type_Declaration (N : Node_Id) is
      Loc     : constant Source_Ptr := Sloc (N);
      Prottyp : constant Entity_Id  := Defining_Identifier (N);
      Protnm  : constant Name_Id    := Chars (Prottyp);

      Pdef : constant Node_Id    := Protected_Definition (N);
      --  This contains two lists; one for visible and one for private decls

      Rec_Decl : Node_Id;
      Cdecls   : List_Id;
      Discr_Map    : Elist_Id := New_Elmt_List;
      Priv         : Node_Id;
      Pent         : Entity_Id;
      New_Priv     : Node_Id;
      Comp         : Node_Id;
      Comp_Id      : Entity_Id;
      Sub          : Node_Id;
      Current_Node : Node_Id := N;
      Nam          : Name_Id;
      Bdef         : Entity_Id := Empty; -- avoid uninit warning
      Edef         : Entity_Id := Empty; -- avoid uninit warning
      Entries_Aggr : Node_Id;
      Body_Id      : Entity_Id;
      Body_Arr     : Node_Id;
      E_Count      : Int;
      Object_Comp  : Node_Id;

      procedure Register_Handler;
      --  for a protected operation that is an interrupt handler, add the
      --  freeze action that will register it as such.

      ----------------------
      -- Register_Handler --
      ----------------------

      procedure Register_Handler is

         --  All semantic checks already done in Sem_Prag

         Prot_Proc    : constant Entity_Id :=
                       Defining_Unit_Name
                         (Specification (Current_Node));

         Proc_Address : constant Node_Id :=
                          Make_Attribute_Reference (Loc,
                          Prefix => New_Reference_To (Prot_Proc, Loc),
                          Attribute_Name => Name_Address);

         RTS_Call     : constant Entity_Id :=
                          Make_Procedure_Call_Statement (Loc,
                            Name =>
                              New_Reference_To (
                                RTE (RE_Register_Interrupt_Handler), Loc),
                            Parameter_Associations =>
                              New_List (Proc_Address));
      begin
         Append_Freeze_Action (Prot_Proc, RTS_Call);
      end Register_Handler;

   --  Start of processing for Expand_N_Protected_Type_Declaration

   begin
      if Present (Corresponding_Record_Type (Prottyp)) then
         return;
      else
         Rec_Decl := Build_Corresponding_Record (N, Prottyp, Loc);
         Cdecls   := Component_Items
                      (Component_List (Type_Definition (Rec_Decl)));
      end if;

      Qualify_Entity_Names (N);

      --  If the type has discriminants, their occurrences in the declaration
      --  have been replaced by the corresponding discriminals. For components
      --  that are constrained by discriminants, their homologues in the
      --  corresponding record type must refer to the discriminants of that
      --  record, so we must apply a new renaming to subtypes_indications:

      --     protected discriminant => discriminal => record discriminant.
      --  This replacement is not applied to default expressions, for which
      --  the discriminal is correct.

      if Has_Discriminants (Prottyp) then
         declare
            Disc : Entity_Id;
            Decl : Node_Id;

         begin
            Disc := First_Discriminant (Prottyp);
            Decl := First (Discriminant_Specifications (Rec_Decl));

            while Present (Disc) loop
               Append_Elmt (Discriminal (Disc), Discr_Map);
               Append_Elmt (Defining_Identifier (Decl), Discr_Map);
               Next_Discriminant (Disc);
               Next (Decl);
            end loop;
         end;
      end if;

      --  Fill in the component declarations.

      --  Add components for entry families. For each entry family,
      --  create an anonymous type declaration with the same size, and
      --  analyze the type.

      Collect_Entry_Families (Loc, Cdecls, Current_Node, Prottyp);

      --  Prepend the _Object field with the right type to the component
      --  list. We need to compute the number of entries, and in some cases
      --  the number of Attach_Handler pragmas.

      declare
         Ritem              : Node_Id;
         Num_Attach_Handler : Int := 0;
         Protection_Subtype : Node_Id;
         Entry_Count_Expr   : constant Node_Id :=
                                Build_Entry_Count_Expression
                                  (Prottyp, Cdecls, Loc);

      begin
         if Has_Attach_Handler (Prottyp) then
            Ritem := First_Rep_Item (Prottyp);
            while Present (Ritem) loop
               if Nkind (Ritem) = N_Pragma
                 and then Chars (Ritem) = Name_Attach_Handler
               then
                  Num_Attach_Handler := Num_Attach_Handler + 1;
               end if;

               Next_Rep_Item (Ritem);
            end loop;

            if Restricted_Profile then
               Protection_Subtype :=
                 New_Reference_To (RTE (RE_Protection_Entry), Loc);

            else
               Protection_Subtype :=
                 Make_Subtype_Indication
                   (Sloc => Loc,
                    Subtype_Mark =>
                      New_Reference_To
                        (RTE (RE_Static_Interrupt_Protection), Loc),
                    Constraint =>
                      Make_Index_Or_Discriminant_Constraint (
                        Sloc => Loc,
                        Constraints => New_List (
                          Entry_Count_Expr,
                          Make_Integer_Literal (Loc, Num_Attach_Handler))));
            end if;

         elsif Has_Interrupt_Handler (Prottyp) then
            Protection_Subtype :=
               Make_Subtype_Indication (
                 Sloc => Loc,
                 Subtype_Mark => New_Reference_To
                   (RTE (RE_Dynamic_Interrupt_Protection), Loc),
                 Constraint =>
                   Make_Index_Or_Discriminant_Constraint (
                     Sloc => Loc,
                     Constraints => New_List (Entry_Count_Expr)));

         elsif Has_Entries (Prottyp) then
            if Abort_Allowed
              or else Restrictions (No_Entry_Queue) = False
              or else Number_Entries (Prottyp) > 1
            then
               Protection_Subtype :=
                  Make_Subtype_Indication (
                    Sloc => Loc,
                    Subtype_Mark =>
                      New_Reference_To (RTE (RE_Protection_Entries), Loc),
                    Constraint =>
                      Make_Index_Or_Discriminant_Constraint (
                        Sloc => Loc,
                        Constraints => New_List (Entry_Count_Expr)));

            else
               Protection_Subtype :=
                 New_Reference_To (RTE (RE_Protection_Entry), Loc);
            end if;

         else
            Protection_Subtype := New_Reference_To (RTE (RE_Protection), Loc);
         end if;

         Object_Comp :=
           Make_Component_Declaration (Loc,
             Defining_Identifier =>
               Make_Defining_Identifier (Loc, Name_uObject),
             Aliased_Present     => True,
             Subtype_Indication  => Protection_Subtype);
      end;

      pragma Assert (Present (Pdef));

      --  Add private field components.

      if Present (Private_Declarations (Pdef)) then
         Priv := First (Private_Declarations (Pdef));

         while Present (Priv) loop

            if Nkind (Priv) = N_Component_Declaration then
               Pent := Defining_Identifier (Priv);
               New_Priv :=
                 Make_Component_Declaration (Loc,
                   Defining_Identifier =>
                     Make_Defining_Identifier (Sloc (Pent), Chars (Pent)),
                   Subtype_Indication =>
                     New_Copy_Tree (Subtype_Indication (Priv), Discr_Map),
                   Expression => Expression (Priv));

               Append_To (Cdecls, New_Priv);

            elsif Nkind (Priv) = N_Subprogram_Declaration then

               --  Make the unprotected version of the subprogram available
               --  for expansion of intra object calls. There is need for
               --  a protected version only if the subprogram is an interrupt
               --  handler, otherwise  this operation can only be called from
               --  within the body.

               Sub :=
                 Make_Subprogram_Declaration (Loc,
                   Specification =>
                     Build_Protected_Sub_Specification
                       (Priv, Prottyp, Unprotected => True));

               Insert_After (Current_Node, Sub);
               Analyze (Sub);

               Set_Protected_Body_Subprogram
                 (Defining_Unit_Name (Specification (Priv)),
                  Defining_Unit_Name (Specification (Sub)));

               Current_Node := Sub;
               if Is_Interrupt_Handler
                 (Defining_Unit_Name (Specification (Priv)))
               then
                  Sub :=
                    Make_Subprogram_Declaration (Loc,
                      Specification =>
                        Build_Protected_Sub_Specification
                          (Priv, Prottyp, Unprotected => False));

                  Insert_After (Current_Node, Sub);
                  Analyze (Sub);
                  Current_Node := Sub;

                  if not Restricted_Profile then
                     Register_Handler;
                  end if;
               end if;
            end if;

            Next (Priv);
         end loop;
      end if;

      --  Put the _Object component after the private component so that it
      --  be finalized early as required by 9.4 (20)

      Append_To (Cdecls, Object_Comp);

      Insert_After (Current_Node, Rec_Decl);
      Current_Node := Rec_Decl;

      --  Analyze the record declaration immediately after construction,
      --  because the initialization procedure is needed for single object
      --  declarations before the next entity is analyzed (the freeze call
      --  that generates this initialization procedure is found below).

      Analyze (Rec_Decl, Suppress => All_Checks);

      --  Collect pointers to entry bodies and their barriers, to be placed
      --  in the Entry_Bodies_Array for the type. For each entry/family we
      --  add an expression to the aggregate which is the initial value of
      --  this array. The array is declared after all protected subprograms.

      if Has_Entries (Prottyp) then
         Entries_Aggr :=
           Make_Aggregate (Loc, Expressions => New_List);

      else
         Entries_Aggr := Empty;
      end if;

      --  Build two new procedure specifications for each protected
      --  subprogram; one to call from outside the object and one to
      --  call from inside. Build a barrier function and an entry
      --  body action procedure specification for each protected entry.
      --  Initialize the entry body array.

      E_Count := 0;

      Comp := First (Visible_Declarations (Pdef));

      while Present (Comp) loop
         if Nkind (Comp) = N_Subprogram_Declaration then
            Sub :=
              Make_Subprogram_Declaration (Loc,
                Specification =>
                  Build_Protected_Sub_Specification
                    (Comp, Prottyp, Unprotected => True));

            Insert_After (Current_Node, Sub);
            Analyze (Sub);

            Set_Protected_Body_Subprogram
              (Defining_Unit_Name (Specification (Comp)),
               Defining_Unit_Name (Specification (Sub)));

            --  Make the protected version of the subprogram available
            --  for expansion of external calls.

            Current_Node := Sub;

            Sub :=
              Make_Subprogram_Declaration (Loc,
                Specification =>
                  Build_Protected_Sub_Specification
                    (Comp, Prottyp, Unprotected => False));

            Insert_After (Current_Node, Sub);
            Analyze (Sub);
            Current_Node := Sub;

            --  If a pragma Interrupt_Handler applies, build and add
            --  a call to Register_Interrupt_Handler to the freezing actions
            --  of the protected version (Current_Node) of the subprogram:
            --    system.interrupts.register_interrupt_handler
            --       (prot_procP'address);

            if not Restricted_Profile
              and then Is_Interrupt_Handler
                (Defining_Unit_Name (Specification (Comp)))
            then
               Register_Handler;
            end if;

         elsif Nkind (Comp) = N_Entry_Declaration then
            E_Count := E_Count + 1;
            Comp_Id := Defining_Identifier (Comp);
            Set_Privals_Chain (Comp_Id, New_Elmt_List);
            Nam := Chars (Comp_Id);
            Edef :=
              Make_Defining_Identifier (Loc,
                Build_Selected_Name (Protnm, New_Internal_Name ('E')));
            Sub :=
              Make_Subprogram_Declaration (Loc,
                Specification =>
                  Build_Protected_Entry_Specification (Edef, Comp_Id, Loc));

            Insert_After (Current_Node, Sub);
            Analyze (Sub);

            Set_Protected_Body_Subprogram (
              Defining_Identifier (Comp),
              Defining_Unit_Name (Specification (Sub)));

            Current_Node := Sub;

            Bdef :=
              Make_Defining_Identifier (Loc,
                Build_Selected_Name (Protnm, New_Internal_Name ('B')));
            Sub :=
              Make_Subprogram_Declaration (Loc,
                Specification =>
                  Build_Barrier_Function_Specification (Bdef, Loc));

            Insert_After (Current_Node, Sub);
            Analyze (Sub);
            Set_Protected_Body_Subprogram (Bdef, Bdef);
            Set_Barrier_Function (Comp_Id, Bdef);
            Set_Scope (Bdef, Scope (Comp_Id));
            Current_Node := Sub;

            --  Collect pointers to the protected subprogram and the barrier
            --  of the current entry, for insertion into Entry_Bodies_Array.

            Append (
              Make_Aggregate (Loc,
                Expressions => New_List (
                  Make_Attribute_Reference (Loc,
                    Prefix => New_Reference_To (Bdef, Loc),
                    Attribute_Name => Name_Unrestricted_Access),
                  Make_Attribute_Reference (Loc,
                    Prefix => New_Reference_To (Edef, Loc),
                    Attribute_Name => Name_Unrestricted_Access))),
              Expressions (Entries_Aggr));

         end if;

         Next (Comp);
      end loop;

      --  If there are some private entry declarations, expand it as if they
      --  were visible entries.

      if Present (Private_Declarations (Pdef)) then
         Comp := First (Private_Declarations (Pdef));

         while Present (Comp) loop
            if Nkind (Comp) = N_Entry_Declaration then
               E_Count := E_Count + 1;
               Comp_Id := Defining_Identifier (Comp);
               Set_Privals_Chain (Comp_Id, New_Elmt_List);
               Nam := Chars (Comp_Id);
               Edef :=
                 Make_Defining_Identifier (Loc,
                   Build_Selected_Name (Protnm, New_Internal_Name ('E')));

               Sub :=
                 Make_Subprogram_Declaration (Loc,
                   Specification =>
                     Build_Protected_Entry_Specification (Edef, Comp_Id, Loc));

               Insert_After (Current_Node, Sub);
               Analyze (Sub);

               Set_Protected_Body_Subprogram (
                 Defining_Identifier (Comp),
                 Defining_Unit_Name (Specification (Sub)));

               Current_Node := Sub;

               Bdef :=
                 Make_Defining_Identifier (Loc,
                   Build_Selected_Name (Protnm, New_Internal_Name ('B')));
               Sub :=
                 Make_Subprogram_Declaration (Loc,
                   Specification =>
                     Build_Barrier_Function_Specification (Bdef, Loc));

               Insert_After (Current_Node, Sub);
               Analyze (Sub);
               Set_Protected_Body_Subprogram (Bdef, Bdef);
               Set_Barrier_Function (Comp_Id, Bdef);
               Set_Scope (Bdef, Scope (Comp_Id));
               Current_Node := Sub;

               --  Collect pointers to the protected subprogram and the
               --   barrier of the current entry, for insertion into
               --  Entry_Bodies_Array.

               Append (
                 Make_Aggregate (Loc,
                   Expressions => New_List (
                     Make_Attribute_Reference (Loc,
                       Prefix => New_Reference_To (Bdef, Loc),
                       Attribute_Name => Name_Unrestricted_Access),
                     Make_Attribute_Reference (Loc,
                       Prefix => New_Reference_To (Edef, Loc),
                       Attribute_Name => Name_Unrestricted_Access))),
                 Expressions (Entries_Aggr));
            end if;

            Next (Comp);
         end loop;
      end if;

      --  Emit declaration for Entry_Bodies_Array, now that the addresses of
      --  all protected subprograms have been collected.

      if Has_Entries (Prottyp) then
         Body_Id := Make_Defining_Identifier (Sloc (Prottyp),
           New_External_Name (Chars (Prottyp), 'A'));

         if Abort_Allowed
           or else Restrictions (No_Entry_Queue) = False
           or else E_Count > 1
         then
            Body_Arr := Make_Object_Declaration (Loc,
              Defining_Identifier => Body_Id,
              Aliased_Present => True,
              Object_Definition =>
                Make_Subtype_Indication (Loc,
                  Subtype_Mark => New_Reference_To (
                    RTE (RE_Protected_Entry_Body_Array), Loc),
                  Constraint =>
                    Make_Index_Or_Discriminant_Constraint (Loc,
                      Constraints => New_List (
                         Make_Range (Loc,
                           Make_Integer_Literal (Loc, 1),
                           Make_Integer_Literal (Loc, E_Count))))),
              Expression => Entries_Aggr);

         else
            Body_Arr := Make_Object_Declaration (Loc,
              Defining_Identifier => Body_Id,
              Aliased_Present => True,
              Object_Definition => New_Reference_To (RTE (RE_Entry_Body), Loc),
              Expression =>
                Make_Aggregate (Loc,
                  Expressions => New_List (
                    Make_Attribute_Reference (Loc,
                      Prefix => New_Reference_To (Bdef, Loc),
                      Attribute_Name => Name_Unrestricted_Access),
                    Make_Attribute_Reference (Loc,
                      Prefix => New_Reference_To (Edef, Loc),
                      Attribute_Name => Name_Unrestricted_Access))));
         end if;

         --  A pointer to this array will be placed in the corresponding
         --  record by its initialization procedure, so this needs to be
         --  analyzed here.

         Insert_After (Current_Node, Body_Arr);
         Current_Node := Body_Arr;
         Analyze (Body_Arr);

         Set_Entry_Bodies_Array (Prottyp, Body_Id);

         --  Finally, build the function that maps an entry index into the
         --  corresponding body. A pointer to this function is placed in each
         --  object of the type. Except for a ravenscar-like profile (no abort,
         --  no entry queue, 1 entry)

         if Abort_Allowed
           or else Restrictions (No_Entry_Queue) = False
           or else E_Count > 1
         then
            Sub :=
              Make_Subprogram_Declaration (Loc,
                Specification => Build_Find_Body_Index_Spec (Prottyp));
            Insert_After (Current_Node, Sub);
            Analyze (Sub);
         end if;
      end if;
   end Expand_N_Protected_Type_Declaration;

   --------------------------------
   -- Expand_N_Requeue_Statement --
   --------------------------------

   --  A requeue statement is expanded into one of four GNARLI operations,
   --  depending on the source and destination (task or protected object).
   --  In addition, code must be generated to jump around the remainder of
   --  processing for the original entry and, if the destination is a
   --  (different) protected object, to attempt to service it.
   --  The following illustrates the various cases:

   --  procedure entE
   --    (O : System.Address;
   --     P : System.Address;
   --     E : Protected_Entry_Index)
   --  is
   --     <discriminant renamings>
   --     <private object renamings>
   --     type poVP is access poV;
   --     _Object : ptVP := ptVP!(O);
   --
   --  begin
   --     begin
   --        <start of statement sequence for entry>
   --
   --        -- Requeue from one protected entry body to another protected
   --        -- entry.
   --
   --        Requeue_Protected_Entry (
   --          _object._object'Access,
   --          new._object'Access,
   --          E,
   --          Abort_Present);
   --        return;
   --
   --        <some more of the statement sequence for entry>
   --
   --        --  Requeue from an entry body to a task entry.
   --
   --        Requeue_Protected_To_Task_Entry (
   --          New._task_id,
   --          E,
   --          Abort_Present);
   --        return;
   --
   --        <rest of statement sequence for entry>
   --        Complete_Entry_Body (_Object._Object);
   --
   --     exception
   --        when all others =>
   --           Exceptional_Complete_Entry_Body (
   --             _Object._Object, Get_GNAT_Exception);
   --     end;
   --  end entE;

   --  Requeue of a task entry call to a task entry.
   --
   --  Accept_Call (E, Ann);
   --     <start of statement sequence for accept statement>
   --     Requeue_Task_Entry (New._task_id, E, Abort_Present);
   --     goto Lnn;
   --     <rest of statement sequence for accept statement>
   --     <<Lnn>>
   --     Complete_Rendezvous;
   --  exception
   --     when all others =>
   --        Exceptional_Complete_Rendezvous (Get_GNAT_Exception);

   --  Requeue of a task entry call to a protected entry.
   --
   --  Accept_Call (E, Ann);
   --     <start of statement sequence for accept statement>
   --     Requeue_Task_To_Protected_Entry (
   --       new._object'Access,
   --       E,
   --       Abort_Present);
   --     newS (new, Pnn);
   --     goto Lnn;
   --     <rest of statement sequence for accept statement>
   --     <<Lnn>>
   --     Complete_Rendezvous;
   --  exception
   --     when all others =>
   --        Exceptional_Complete_Rendezvous (Get_GNAT_Exception);

   --  Further details on these expansions can be found in
   --  Expand_N_Protected_Body and Expand_N_Accept_Statement.

   procedure Expand_N_Requeue_Statement (N : Node_Id) is
      Loc        : constant Source_Ptr := Sloc (N);
      Acc_Stat   : Node_Id;
      Concval    : Node_Id;
      Ename      : Node_Id;
      Index      : Node_Id;
      Conctyp    : Entity_Id;
      Oldtyp     : Entity_Id;
      Lab_Node   : Node_Id;
      Rcall      : Node_Id;
      Abortable  : Node_Id;
      Skip_Stat  : Node_Id;
      Self_Param : Node_Id;
      New_Param  : Node_Id;
      Params     : List_Id;
      RTS_Call   : Entity_Id;

   begin
      if Abort_Present (N) then
         Abortable := New_Occurrence_Of (Standard_True, Loc);
      else
         Abortable := New_Occurrence_Of (Standard_False, Loc);
      end if;

      --  Set up the target object.

      Extract_Entry (N, Concval, Ename, Index);
      Conctyp := Etype (Concval);
      New_Param := Concurrent_Ref (Concval);

      --  The target entry index and abortable flag are the same for all cases.

      Params := New_List (
        Entry_Index_Expression (Loc, Entity (Ename), Index, Conctyp),
        Abortable);

      --  Determine proper GNARLI call and required additional parameters
      --  Loop to find nearest enclosing task type or protected type

      Oldtyp := Current_Scope;
      loop
         if Is_Task_Type (Oldtyp) then
            if Is_Task_Type (Conctyp) then
               RTS_Call := RTE (RE_Requeue_Task_Entry);

            else
               pragma Assert (Is_Protected_Type (Conctyp));
               RTS_Call := RTE (RE_Requeue_Task_To_Protected_Entry);
               New_Param :=
                 Make_Attribute_Reference (Loc,
                   Prefix => New_Param,
                   Attribute_Name => Name_Unchecked_Access);
            end if;

            Prepend (New_Param, Params);
            exit;

         elsif Is_Protected_Type (Oldtyp) then
            Self_Param :=
              Make_Attribute_Reference (Loc,
                Prefix => Concurrent_Ref (New_Occurrence_Of (Oldtyp, Loc)),
                Attribute_Name => Name_Unchecked_Access);

            if Is_Task_Type (Conctyp) then
               RTS_Call := RTE (RE_Requeue_Protected_To_Task_Entry);

            else
               pragma Assert (Is_Protected_Type (Conctyp));
               RTS_Call := RTE (RE_Requeue_Protected_Entry);
               New_Param :=
                 Make_Attribute_Reference (Loc,
                   Prefix => New_Param,
                   Attribute_Name => Name_Unchecked_Access);
            end if;

            Prepend (New_Param, Params);
            Prepend (Self_Param, Params);
            exit;

         --  If neither task type or protected type, must be in some
         --  inner enclosing block, so move on out

         else
            Oldtyp := Scope (Oldtyp);
         end if;
      end loop;

      --  Create the GNARLI call.

      Rcall := Make_Procedure_Call_Statement (Loc,
        Name =>
          New_Occurrence_Of (RTS_Call, Loc),
        Parameter_Associations => Params);

      Rewrite (N, Rcall);
      Analyze (N);

      if Is_Protected_Type (Oldtyp) then

         --  Build the return statement to skip the rest of the entry body

         Skip_Stat := Make_Return_Statement (Loc);

      else
         --  If the requeue is within a task, find the end label of the
         --  enclosing accept statement.

         Acc_Stat := Parent (N);
         while Nkind (Acc_Stat) /= N_Accept_Statement loop
            Acc_Stat := Parent (Acc_Stat);
         end loop;

         --  The last statement is the second label, used for completing the
         --  rendezvous the usual way.
         --  The label we are looking for is right before it.

         Lab_Node :=
           Prev (Last (Statements (Handled_Statement_Sequence (Acc_Stat))));

         pragma Assert (Nkind (Lab_Node) = N_Label);

         --  Build the goto statement to skip the rest of the accept
         --  statement.

         Skip_Stat :=
           Make_Goto_Statement (Loc,
             Name => New_Occurrence_Of (Entity (Identifier (Lab_Node)), Loc));
      end if;

      Set_Analyzed (Skip_Stat);

      Insert_After (N, Skip_Stat);

   end Expand_N_Requeue_Statement;

   -------------------------------
   -- Expand_N_Selective_Accept --
   -------------------------------

   procedure Expand_N_Selective_Accept (N : Node_Id) is
      Loc            : constant Source_Ptr := Sloc (N);
      Alts           : constant List_Id    := Select_Alternatives (N);

      Accept_Case    : List_Id;
      Accept_List    : List_Id := New_List;

      Alt            : Node_Id;
      Alt_List       : List_Id := New_List;
      Alt_Stats      : List_Id;
      Ann            : Entity_Id := Empty;

      Block          : Node_Id;
      Check_Guard    : Boolean := True;
      Decls          : List_Id := New_List;
      Stats          : List_Id := New_List;

      Body_List      : List_Id := New_List;
      Trailing_List  : List_Id := New_List;

      Choices        : List_Id;
      Else_Present   : Boolean := False;
      Terminate_Alt  : Node_Id := Empty;
      Select_Mode    : Node_Id;

      Delay_Case     : List_Id;
      Delay_Count    : Integer := 0;
      Delay_Val      : Entity_Id;
      Delay_Index    : Entity_Id;
      Delay_Min      : Entity_Id;
      Delay_Num      : Int := 1;
      Delay_Alt_List : List_Id := New_List;
      Delay_List     : List_Id := New_List;
      D              : Entity_Id;
      M              : Entity_Id;

      First_Delay    : Boolean := True;
      Guard_Open     : Entity_Id;

      End_Lab        : Node_Id;
      Index          : Int := 1;
      Lab            : Node_Id;
      Num_Alts       : Int;
      Num_Accept     : Nat := 0;
      Proc           : Node_Id;
      Q              : Node_Id;
      Time_Type      : Entity_Id;
      X              : Node_Id;
      Select_Call    : Node_Id;

      Qnam : constant Entity_Id :=
               Make_Defining_Identifier (Loc, New_External_Name ('S', 0));

      Xnam : constant Entity_Id :=
               Make_Defining_Identifier (Loc, New_External_Name ('J', 1));

      -----------------------
      -- Local subprograms --
      -----------------------

      function Accept_Or_Raise return List_Id;
      --  For the rare case where delay alternatives all have guards, and
      --  all of them are closed, it is still possible that there were open
      --  accept alternatives with no callers. We must reexamine the
      --  Accept_List, and execute a selective wait with no else if some
      --  accept is open. If none, we raise program_error.

      procedure Add_Accept (Alt : Node_Id);
      --  Process a single accept statement in a select alternative. Build
      --  procedure for body of accept, and add entry to dispatch table with
      --  expression for guard, in preparation for call to run time select.

      function Make_And_Declare_Label (Num : Int) return Node_Id;
      --  Manufacture a label using Num as a serial number and declare it.
      --  The declaration is appended to Decls. The label marks the trailing
      --  statements of an accept or delay alternative.

      function Make_Select_Call (Select_Mode : Entity_Id) return Node_Id;
      --  Build call to Selective_Wait runtime routine.

      procedure Process_Delay_Alternative (Alt : Node_Id; Index : Int);
      --  Add code to compare value of delay with previous values, and
      --  generate case entry for trailing statements.

      procedure Process_Accept_Alternative
        (Alt   : Node_Id;
         Index : Int;
         Proc  : Node_Id);
      --  Add code to call corresponding procedure, and branch to
      --  trailing statements, if any.

      ---------------------
      -- Accept_Or_Raise --
      ---------------------

      function Accept_Or_Raise return List_Id is
         Cond  : Node_Id;
         Stats : List_Id;
         J     : constant Entity_Id := Make_Defining_Identifier (Loc,
                                                  New_Internal_Name ('J'));

      begin
         --  We generate the following:

         --    for J in q'range loop
         --       if q(J).S /=null_task_entry then
         --          selective_wait (simple_mode,...);
         --          done := True;
         --          exit;
         --       end if;
         --    end loop;
         --
         --    if no rendez_vous then
         --       raise program_error;
         --    end if;

         --    Note that the code needs to know that the selector name
         --    in an Accept_Alternative is named S.

         Cond := Make_Op_Ne (Loc,
           Left_Opnd =>
             Make_Selected_Component (Loc,
               Prefix => Make_Indexed_Component (Loc,
                 Prefix => New_Reference_To (Qnam, Loc),
                   Expressions => New_List (New_Reference_To (J, Loc))),
             Selector_Name => Make_Identifier (Loc, Name_S)),
           Right_Opnd =>
             New_Reference_To (RTE (RE_Null_Task_Entry), Loc));

         Stats := New_List (
           Make_Implicit_Loop_Statement (N,
             Identifier => Empty,
             Iteration_Scheme =>
               Make_Iteration_Scheme (Loc,
                 Loop_Parameter_Specification =>
                   Make_Loop_Parameter_Specification (Loc,
                     Defining_Identifier => J,
                     Discrete_Subtype_Definition =>
                       Make_Attribute_Reference (Loc,
                         Prefix => New_Reference_To (Qnam, Loc),
                         Attribute_Name => Name_Range,
                         Expressions => New_List (
                           Make_Integer_Literal (Loc, 1))))),

             Statements => New_List (
               Make_Implicit_If_Statement (N,
                 Condition =>  Cond,
                 Then_Statements => New_List (
                   Make_Select_Call (
                    New_Reference_To (RTE (RE_Simple_Mode), Loc)),
                   Make_Exit_Statement (Loc))))));

         Append_To (Stats,
           Make_Raise_Program_Error (Loc,
             Condition => Make_Op_Eq (Loc,
               Left_Opnd  => New_Reference_To (Xnam, Loc),
               Right_Opnd =>
                 New_Reference_To (RTE (RE_No_Rendezvous), Loc)),
             Reason => PE_All_Guards_Closed));

         return Stats;
      end Accept_Or_Raise;

      ----------------
      -- Add_Accept --
      ----------------

      procedure Add_Accept (Alt : Node_Id) is
         Acc_Stm   : constant Node_Id    := Accept_Statement (Alt);
         Ename     : constant Node_Id    := Entry_Direct_Name (Acc_Stm);
         Eent      : constant Entity_Id  := Entity (Ename);
         Index     : constant Node_Id    := Entry_Index (Acc_Stm);
         Null_Body : Node_Id;
         Proc_Body : Node_Id;
         PB_Ent    : Entity_Id;
         Expr      : Node_Id;
         Call      : Node_Id;

      begin
         if No (Ann) then
            Ann := Node (Last_Elmt (Accept_Address (Eent)));
         end if;

         if Present (Condition (Alt)) then
            Expr :=
              Make_Conditional_Expression (Loc, New_List (
                Condition (Alt),
                Entry_Index_Expression (Loc, Eent, Index, Scope (Eent)),
                New_Reference_To (RTE (RE_Null_Task_Entry), Loc)));
         else
            Expr :=
              Entry_Index_Expression
                (Loc, Eent, Index, Scope (Eent));
         end if;

         if Present (Handled_Statement_Sequence (Accept_Statement (Alt))) then
            Null_Body := New_Reference_To (Standard_False, Loc);

            if Abort_Allowed then
               Call := Make_Procedure_Call_Statement (Loc,
                 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc));
               Insert_Before (First (Statements (Handled_Statement_Sequence (
                 Accept_Statement (Alt)))), Call);
               Analyze (Call);
            end if;

            PB_Ent :=
              Make_Defining_Identifier (Sloc (Ename),
                New_External_Name (Chars (Ename), 'A', Num_Accept));

            Proc_Body :=
              Make_Subprogram_Body (Loc,
                Specification =>
                  Make_Procedure_Specification (Loc,
                    Defining_Unit_Name => PB_Ent),
               Declarations => Declarations (Acc_Stm),
               Handled_Statement_Sequence =>
                 Build_Accept_Body (Accept_Statement (Alt)));

            --  During the analysis of the body of the accept statement, any
            --  zero cost exception handler records were collected in the
            --  Accept_Handler_Records field of the N_Accept_Alternative
            --  node. This is where we move them to where they belong,
            --  namely the newly created procedure.

            Set_Handler_Records (PB_Ent, Accept_Handler_Records (Alt));
            Append (Proc_Body, Body_List);

         else
            Null_Body := New_Reference_To (Standard_True,  Loc);

            --  if accept statement has declarations, insert above, given
            --  that we are not creating a body for the accept.

            if Present (Declarations (Acc_Stm)) then
               Insert_Actions (N, Declarations (Acc_Stm));
            end if;
         end if;

         Append_To (Accept_List,
           Make_Aggregate (Loc, Expressions => New_List (Null_Body, Expr)));

         Num_Accept := Num_Accept + 1;

      end Add_Accept;

      ----------------------------
      -- Make_And_Declare_Label --
      ----------------------------

      function Make_And_Declare_Label (Num : Int) return Node_Id is
         Lab_Id : Node_Id;

      begin
         Lab_Id := Make_Identifier (Loc, New_External_Name ('L', Num));
         Lab :=
           Make_Label (Loc, Lab_Id);

         Append_To (Decls,
           Make_Implicit_Label_Declaration (Loc,
             Defining_Identifier  =>
               Make_Defining_Identifier (Loc, Chars (Lab_Id)),
             Label_Construct => Lab));

         return Lab;
      end Make_And_Declare_Label;

      ----------------------
      -- Make_Select_Call --
      ----------------------

      function Make_Select_Call (Select_Mode : Entity_Id) return Node_Id is
         Params : List_Id := New_List;

      begin
         Append (
           Make_Attribute_Reference (Loc,
             Prefix => New_Reference_To (Qnam, Loc),
             Attribute_Name => Name_Unchecked_Access),
           Params);
         Append (Select_Mode, Params);
         Append (New_Reference_To (Ann, Loc), Params);
         Append (New_Reference_To (Xnam, Loc), Params);

         return
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Selective_Wait), Loc),
             Parameter_Associations => Params);
      end Make_Select_Call;

      --------------------------------
      -- Process_Accept_Alternative --
      --------------------------------

      procedure Process_Accept_Alternative
        (Alt   : Node_Id;
         Index : Int;
         Proc  : Node_Id)
      is
         Choices   : List_Id := No_List;
         Alt_Stats : List_Id;

      begin
         Adjust_Condition (Condition (Alt));
         Alt_Stats := No_List;

         if Present (Handled_Statement_Sequence (Accept_Statement (Alt))) then
            Choices := New_List (
              Make_Integer_Literal (Loc, Index));

            Alt_Stats := New_List (
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (
                  Defining_Unit_Name (Specification (Proc)), Loc)));
         end if;

         if Statements (Alt) /= Empty_List then

            if No (Alt_Stats) then

               --  Accept with no body, followed by trailing statements.

               Choices := New_List (
                 Make_Integer_Literal (Loc, Index));

               Alt_Stats := New_List;
            end if;

            --  After the call, if any, branch to to trailing statements.
            --  We create a label for each, as well as the corresponding
            --  label declaration.

            Lab := Make_And_Declare_Label (Index);
            Append_To (Alt_Stats,
              Make_Goto_Statement (Loc,
                Name => New_Copy (Identifier (Lab))));

            Append (Lab, Trailing_List);
            Append_List (Statements (Alt), Trailing_List);
            Append_To (Trailing_List,
              Make_Goto_Statement (Loc,
                Name => New_Copy (Identifier (End_Lab))));
         end if;

         if Present (Alt_Stats) then

            --  Procedure call. and/or trailing statements

            Append_To (Alt_List,
              Make_Case_Statement_Alternative (Loc,
                Discrete_Choices => Choices,
                Statements => Alt_Stats));
         end if;
      end Process_Accept_Alternative;

      -------------------------------
      -- Process_Delay_Alternative --
      -------------------------------

      procedure Process_Delay_Alternative (Alt : Node_Id; Index : Int) is
         Choices   : List_Id;
         Cond      : Node_Id;
         Delay_Alt : List_Id;

      begin
         --  Deal with C/Fortran boolean as delay condition

         Adjust_Condition (Condition (Alt));

         --  Determine the smallest specified delay.
         --  for each delay alternative generate:

         --    if guard-expression then
         --       Delay_Val  := delay-expression;
         --       Guard_Open := True;
         --       if Delay_Val < Delay_Min then
         --          Delay_Min   := Delay_Val;
         --          Delay_Index := Index;
         --       end if;
         --    end if;

         --  The enclosing if-statement is omitted if there is no guard.

         if Delay_Count = 1
           or else First_Delay
         then
            First_Delay := False;

            Delay_Alt := New_List (
              Make_Assignment_Statement (Loc,
                Name => New_Reference_To (Delay_Min, Loc),
                Expression => Expression (Delay_Statement (Alt))));

            if Delay_Count > 1 then
               Append_To (Delay_Alt,
                 Make_Assignment_Statement (Loc,
                   Name       => New_Reference_To (Delay_Index, Loc),
                   Expression => Make_Integer_Literal (Loc, Index)));
            end if;

         else
            Delay_Alt := New_List (
              Make_Assignment_Statement (Loc,
                Name => New_Reference_To (Delay_Val, Loc),
                Expression => Expression (Delay_Statement (Alt))));

            if Time_Type = Standard_Duration then
               Cond :=
                  Make_Op_Lt (Loc,
                    Left_Opnd  => New_Reference_To (Delay_Val, Loc),
                    Right_Opnd => New_Reference_To (Delay_Min, Loc));

            else
               --  The scope of the time type must define a comparison
               --  operator. The scope itself may not be visible, so we
               --  construct a node with entity information to insure that
               --  semantic analysis can find the proper operator.

               Cond :=
                 Make_Function_Call (Loc,
                   Name => Make_Selected_Component (Loc,
                     Prefix => New_Reference_To (Scope (Time_Type), Loc),
                     Selector_Name =>
                       Make_Operator_Symbol (Loc,
                         Chars => Name_Op_Lt,
                         Strval => No_String)),
                    Parameter_Associations =>
                      New_List (
                        New_Reference_To (Delay_Val, Loc),
                        New_Reference_To (Delay_Min, Loc)));

               Set_Entity (Prefix (Name (Cond)), Scope (Time_Type));
            end if;

            Append_To (Delay_Alt,
              Make_Implicit_If_Statement (N,
                Condition => Cond,
                Then_Statements => New_List (
                  Make_Assignment_Statement (Loc,
                    Name       => New_Reference_To (Delay_Min, Loc),
                    Expression => New_Reference_To (Delay_Val, Loc)),

                  Make_Assignment_Statement (Loc,
                    Name       => New_Reference_To (Delay_Index, Loc),
                    Expression => Make_Integer_Literal (Loc, Index)))));
         end if;

         if Check_Guard then
            Append_To (Delay_Alt,
              Make_Assignment_Statement (Loc,
                Name => New_Reference_To (Guard_Open, Loc),
                Expression => New_Reference_To (Standard_True, Loc)));
         end if;

         if Present (Condition (Alt)) then
            Delay_Alt := New_List (
              Make_Implicit_If_Statement (N,
                Condition => Condition (Alt),
                Then_Statements => Delay_Alt));
         end if;

         Append_List (Delay_Alt, Delay_List);

         --  If the delay alternative has a statement part, add a
         --  choice to the case statements for delays.

         if Present (Statements (Alt)) then

            if Delay_Count = 1 then
               Append_List (Statements (Alt), Delay_Alt_List);

            else
               Choices := New_List (
                 Make_Integer_Literal (Loc, Index));

               Append_To (Delay_Alt_List,
                 Make_Case_Statement_Alternative (Loc,
                   Discrete_Choices => Choices,
                   Statements => Statements (Alt)));
            end if;

         elsif Delay_Count = 1 then

            --  If the single delay has no trailing statements, add a branch
            --  to the exit label to the selective wait.

            Delay_Alt_List := New_List (
              Make_Goto_Statement (Loc,
                Name => New_Copy (Identifier (End_Lab))));

         end if;
      end Process_Delay_Alternative;

   --  Start of processing for Expand_N_Selective_Accept

   begin
      --  First insert some declarations before the select. The first is:

      --    Ann : Address

      --  This variable holds the parameters passed to the accept body. This
      --  declaration has already been inserted by the time we get here by
      --  a call to Expand_Accept_Declarations made from the semantics when
      --  processing the first accept statement contained in the select. We
      --  can find this entity as Accept_Address (E), where E is any of the
      --  entries references by contained accept statements.

      --  The first step is to scan the list of Selective_Accept_Statements
      --  to find this entity, and also count the number of accepts, and
      --  determine if terminated, delay or else is present:

      Num_Alts := 0;

      Alt := First (Alts);
      while Present (Alt) loop

         if Nkind (Alt) = N_Accept_Alternative then
            Add_Accept (Alt);

         elsif Nkind (Alt) = N_Delay_Alternative then
            Delay_Count   := Delay_Count + 1;

            --  If the delays are relative delays, the delay expressions have
            --  type Standard_Duration. Otherwise they must have some time type
            --  recognized by GNAT.

            if Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement then
               Time_Type := Standard_Duration;
            else
               Time_Type := Etype (Expression (Delay_Statement (Alt)));

               if Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time)
                 or else Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time)
               then
                  null;
               else
                  Error_Msg_NE (
                    "& is not a time type ('R'M 9.6(6))",
                       Expression (Delay_Statement (Alt)), Time_Type);
                  Time_Type := Standard_Duration;
                  Set_Etype (Expression (Delay_Statement (Alt)), Any_Type);
               end if;
            end if;

            if No (Condition (Alt)) then

               --  This guard will always be open.

               Check_Guard := False;
            end if;

         elsif Nkind (Alt) = N_Terminate_Alternative then
            Adjust_Condition (Condition (Alt));
            Terminate_Alt := Alt;
         end if;

         Num_Alts := Num_Alts + 1;
         Next (Alt);
      end loop;

      Else_Present := Present (Else_Statements (N));

      --  At the same time (see procedure Add_Accept) we build the accept list:

      --    Qnn : Accept_List (1 .. num-select) := (
      --          (null-body, entry-index),
      --          (null-body, entry-index),
      --          ..
      --          (null_body, entry-index));

      --  In the above declaration, null-body is True if the corresponding
      --  accept has no body, and false otherwise. The entry is either the
      --  entry index expression if there is no guard, or if a guard is
      --  present, then a conditional expression of the form:

      --    (if guard then entry-index else Null_Task_Entry)

      --  If a guard is statically known to be false, the entry can simply
      --  be omitted from the accept list.

      Q :=
        Make_Object_Declaration (Loc,
          Defining_Identifier => Qnam,
          Object_Definition =>
            New_Reference_To (RTE (RE_Accept_List), Loc),
          Aliased_Present => True,

          Expression =>
             Make_Qualified_Expression (Loc,
               Subtype_Mark =>
                 New_Reference_To (RTE (RE_Accept_List), Loc),
               Expression =>
                 Make_Aggregate (Loc, Expressions => Accept_List)));

      Append (Q, Decls);

      --  Then we declare the variable that holds the index for the accept
      --  that will be selected for service:

      --    Xnn : Select_Index;

      X :=
        Make_Object_Declaration (Loc,
          Defining_Identifier => Xnam,
          Object_Definition =>
            New_Reference_To (RTE (RE_Select_Index), Loc),
          Expression =>
            New_Reference_To (RTE (RE_No_Rendezvous), Loc));

      Append (X, Decls);

      --  After this follow procedure declarations for each accept body.

      --    procedure Pnn is
      --    begin
      --       ...
      --    end;

      --  where the ... are statements from the corresponding procedure body.
      --  No parameters are involved, since the parameters are passed via Ann
      --  and the parameter references have already been expanded to be direct
      --  references to Ann (see Exp_Ch2.Expand_Entry_Parameter). Furthermore,
      --  any embedded tasking statements (which would normally be illegal in
      --  procedures, have been converted to calls to the tasking runtime so
      --  there is no problem in putting them into procedures.

      --  The original accept statement has been expanded into a block in
      --  the same fashion as for simple accepts (see Build_Accept_Body).

      --  Note: we don't really need to build these procedures for the case
      --  where no delay statement is present, but it is just as easy to
      --  build them unconditionally, and not significantly inefficient,
      --  since if they are short they will be inlined anyway.

      --  The procedure declarations have been assembled in Body_List.

      --  If delays are present, we must compute the required delay.
      --  We first generate the declarations:

      --    Delay_Index : Boolean := 0;
      --    Delay_Min   : Some_Time_Type.Time;
      --    Delay_Val   : Some_Time_Type.Time;

      --  Delay_Index will be set to the index of the minimum delay, i.e. the
      --   active delay that is actually chosen as the basis for the possible
      --   delay if an immediate rendez-vous is not possible.
      --   In the most common case there is a single delay statement, and this
      --   is handled specially.

      if Delay_Count > 0 then

         --  Generate the required declarations

         Delay_Val :=
           Make_Defining_Identifier (Loc, New_External_Name ('D', 1));
         Delay_Index :=
           Make_Defining_Identifier (Loc, New_External_Name ('D', 2));
         Delay_Min :=
           Make_Defining_Identifier (Loc, New_External_Name ('D', 3));

         Append_To (Decls,
           Make_Object_Declaration (Loc,
             Defining_Identifier => Delay_Val,
             Object_Definition   => New_Reference_To (Time_Type, Loc)));

         Append_To (Decls,
           Make_Object_Declaration (Loc,
             Defining_Identifier => Delay_Index,
             Object_Definition   => New_Reference_To (Standard_Integer, Loc),
             Expression          => Make_Integer_Literal (Loc, 0)));

         Append_To (Decls,
           Make_Object_Declaration (Loc,
             Defining_Identifier => Delay_Min,
             Object_Definition   => New_Reference_To (Time_Type, Loc),
             Expression          =>
               Unchecked_Convert_To (Time_Type,
                 Make_Attribute_Reference (Loc,
                   Prefix =>
                     New_Occurrence_Of (Underlying_Type (Time_Type), Loc),
                   Attribute_Name => Name_Last))));

         --  Create Duration and Delay_Mode objects used for passing a delay
         --  value to RTS

         D := Make_Defining_Identifier (Loc, New_Internal_Name ('D'));
         M := Make_Defining_Identifier (Loc, New_Internal_Name ('M'));

         declare
            Discr : Entity_Id;

         begin
            --  Note that these values are defined in s-osprim.ads and must
            --  be kept in sync:
            --
            --     Relative          : constant := 0;
            --     Absolute_Calendar : constant := 1;
            --     Absolute_RT       : constant := 2;

            if Time_Type = Standard_Duration then
               Discr := Make_Integer_Literal (Loc, 0);

            elsif Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) then
               Discr := Make_Integer_Literal (Loc, 1);

            else
               pragma Assert
                 (Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time));
               Discr := Make_Integer_Literal (Loc, 2);
            end if;

            Append_To (Decls,
              Make_Object_Declaration (Loc,
                Defining_Identifier => D,
                Object_Definition =>
                  New_Reference_To (Standard_Duration, Loc)));

            Append_To (Decls,
              Make_Object_Declaration (Loc,
                Defining_Identifier => M,
                Object_Definition   =>
                  New_Reference_To (Standard_Integer, Loc),
                Expression          => Discr));
         end;

         if Check_Guard then
            Guard_Open :=
              Make_Defining_Identifier (Loc, New_External_Name ('G', 1));

            Append_To (Decls,
              Make_Object_Declaration (Loc,
                 Defining_Identifier => Guard_Open,
                 Object_Definition => New_Reference_To (Standard_Boolean, Loc),
                 Expression        => New_Reference_To (Standard_False, Loc)));
         end if;

      --  Delay_Count is zero, don't need M and D set (suppress warning)

      else
         M := Empty;
         D := Empty;
      end if;

      if Present (Terminate_Alt) then

         --  If the terminate alternative guard is False, use
         --  Simple_Mode; otherwise use Terminate_Mode.

         if Present (Condition (Terminate_Alt)) then
            Select_Mode := Make_Conditional_Expression (Loc,
              New_List (Condition (Terminate_Alt),
                        New_Reference_To (RTE (RE_Terminate_Mode), Loc),
                        New_Reference_To (RTE (RE_Simple_Mode), Loc)));
         else
            Select_Mode := New_Reference_To (RTE (RE_Terminate_Mode), Loc);
         end if;

      elsif Else_Present or Delay_Count > 0 then
         Select_Mode := New_Reference_To (RTE (RE_Else_Mode), Loc);

      else
         Select_Mode := New_Reference_To (RTE (RE_Simple_Mode), Loc);
      end if;

      Select_Call := Make_Select_Call (Select_Mode);
      Append (Select_Call, Stats);

      --  Now generate code to act on the result. There is an entry
      --  in this case for each accept statement with a non-null body,
      --  followed by a branch to the statements that follow the Accept.
      --  In the absence of delay alternatives, we generate:

      --    case X is
      --      when No_Rendezvous =>  --  omitted if simple mode
      --         goto Lab0;

      --      when 1 =>
      --         P1n;
      --         goto Lab1;

      --      when 2 =>
      --         P2n;
      --         goto Lab2;

      --      when others =>
      --         goto Exit;
      --    end case;
      --
      --    Lab0: Else_Statements;
      --    goto exit;

      --    Lab1:  Trailing_Statements1;
      --    goto Exit;
      --
      --    Lab2:  Trailing_Statements2;
      --    goto Exit;
      --    ...
      --    Exit:

      --  Generate label for common exit.

      End_Lab := Make_And_Declare_Label (Num_Alts + 1);

      --  First entry is the default case, when no rendezvous is possible.

      Choices := New_List (New_Reference_To (RTE (RE_No_Rendezvous), Loc));

      if Else_Present then

         --  If no rendezvous is possible, the else part is executed.

         Lab := Make_And_Declare_Label (0);
         Alt_Stats := New_List (
           Make_Goto_Statement (Loc,
             Name => New_Copy (Identifier (Lab))));

         Append (Lab, Trailing_List);
         Append_List (Else_Statements (N), Trailing_List);
         Append_To (Trailing_List,
           Make_Goto_Statement (Loc,
             Name => New_Copy (Identifier (End_Lab))));
      else
         Alt_Stats := New_List (
           Make_Goto_Statement (Loc,
             Name => New_Copy (Identifier (End_Lab))));
      end if;

      Append_To (Alt_List,
        Make_Case_Statement_Alternative (Loc,
          Discrete_Choices => Choices,
          Statements => Alt_Stats));

      --  We make use of the fact that Accept_Index is an integer type,
      --  and generate successive literals for entries for each accept.
      --  Only those for which there is a body or trailing statements are
      --  given a case entry.

      Alt := First (Select_Alternatives (N));
      Proc := First (Body_List);

      while Present (Alt) loop

         if Nkind (Alt) = N_Accept_Alternative then
            Process_Accept_Alternative (Alt, Index, Proc);
            Index := Index + 1;

            if Present
              (Handled_Statement_Sequence (Accept_Statement (Alt)))
            then
               Next (Proc);
            end if;

         elsif Nkind (Alt) = N_Delay_Alternative then
            Process_Delay_Alternative (Alt, Delay_Num);
            Delay_Num := Delay_Num + 1;
         end if;

         Next (Alt);
      end loop;

      --  An others choice is always added to the main case, as well
      --  as the delay case (to satisfy the compiler).

      Append_To (Alt_List,
        Make_Case_Statement_Alternative (Loc,
          Discrete_Choices =>
            New_List (Make_Others_Choice (Loc)),
          Statements       =>
            New_List (Make_Goto_Statement (Loc,
              Name => New_Copy (Identifier (End_Lab))))));

      Accept_Case := New_List (
        Make_Case_Statement (Loc,
          Expression   => New_Reference_To (Xnam, Loc),
          Alternatives => Alt_List));

      Append_List (Trailing_List, Accept_Case);
      Append (End_Lab, Accept_Case);
      Append_List (Body_List, Decls);

      --  Construct case statement for trailing statements of delay
      --  alternatives, if there are several of them.

      if Delay_Count > 1 then
         Append_To (Delay_Alt_List,
           Make_Case_Statement_Alternative (Loc,
             Discrete_Choices =>
               New_List (Make_Others_Choice (Loc)),
             Statements       =>
               New_List (Make_Null_Statement (Loc))));

         Delay_Case := New_List (
           Make_Case_Statement (Loc,
             Expression   => New_Reference_To (Delay_Index, Loc),
             Alternatives => Delay_Alt_List));
      else
         Delay_Case := Delay_Alt_List;
      end if;

      --  If there are no delay alternatives, we append the case statement
      --  to the statement list.

      if Delay_Count = 0 then
         Append_List (Accept_Case, Stats);

      --  Delay alternatives present

      else
         --  If delay alternatives are present we generate:

         --    find minimum delay.
         --    DX := minimum delay;
         --    M := <delay mode>;
         --    Timed_Selective_Wait (Q'Unchecked_Access, Delay_Mode, P,
         --      DX, MX, X);
         --
         --    if X = No_Rendezvous then
         --      case statement for delay statements.
         --    else
         --      case statement for accept alternatives.
         --    end if;

         declare
            Cases : Node_Id;
            Stmt  : Node_Id;
            Parms : List_Id;
            Parm  : Node_Id;
            Conv  : Node_Id;

         begin
            --  The type of the delay expression is known to be legal

            if Time_Type = Standard_Duration then
               Conv := New_Reference_To (Delay_Min, Loc);

            elsif Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) then
               Conv := Make_Function_Call (Loc,
                 New_Reference_To (RTE (RO_CA_To_Duration), Loc),
                 New_List (New_Reference_To (Delay_Min, Loc)));

            else
               pragma Assert
                 (Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time));

               Conv := Make_Function_Call (Loc,
                 New_Reference_To (RTE (RO_RT_To_Duration), Loc),
                 New_List (New_Reference_To (Delay_Min, Loc)));
            end if;

            Stmt := Make_Assignment_Statement (Loc,
              Name => New_Reference_To (D, Loc),
              Expression => Conv);

            --  Change the value for Accept_Modes. (Else_Mode -> Delay_Mode)

            Parms := Parameter_Associations (Select_Call);
            Parm := First (Parms);

            while Present (Parm)
              and then Parm /= Select_Mode
            loop
               Next (Parm);
            end loop;

            pragma Assert (Present (Parm));
            Rewrite (Parm, New_Reference_To (RTE (RE_Delay_Mode), Loc));
            Analyze (Parm);

            --  Prepare two new parameters of Duration and Delay_Mode type
            --  which represent the value and the mode of the minimum delay.

            Next (Parm);
            Insert_After (Parm, New_Reference_To (M, Loc));
            Insert_After (Parm, New_Reference_To (D, Loc));

            --  Create a call to RTS.

            Rewrite (Select_Call,
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (RTE (RE_Timed_Selective_Wait), Loc),
                Parameter_Associations => Parms));

            --  This new call should follow the calculation of the
            --  minimum delay.

            Insert_List_Before (Select_Call, Delay_List);

            if Check_Guard then
               Stmt :=
                 Make_Implicit_If_Statement (N,
                   Condition => New_Reference_To (Guard_Open, Loc),
                   Then_Statements =>
                     New_List (New_Copy_Tree (Stmt),
                       New_Copy_Tree (Select_Call)),
                   Else_Statements => Accept_Or_Raise);
               Rewrite (Select_Call, Stmt);
            else
               Insert_Before (Select_Call, Stmt);
            end if;

            Cases :=
              Make_Implicit_If_Statement (N,
                Condition => Make_Op_Eq (Loc,
                  Left_Opnd  => New_Reference_To (Xnam, Loc),
                  Right_Opnd =>
                    New_Reference_To (RTE (RE_No_Rendezvous), Loc)),

                Then_Statements => Delay_Case,
                Else_Statements => Accept_Case);

            Append (Cases, Stats);
         end;
      end if;

      --  Replace accept statement with appropriate block

      Block :=
        Make_Block_Statement (Loc,
          Declarations => Decls,
          Handled_Statement_Sequence =>
            Make_Handled_Sequence_Of_Statements (Loc,
              Statements => Stats));

      Rewrite (N, Block);
      Analyze (N);

      --  Note: have to worry more about abort deferral in above code ???

      --  Final step is to unstack the Accept_Address entries for all accept
      --  statements appearing in accept alternatives in the select statement

      Alt := First (Alts);
      while Present (Alt) loop
         if Nkind (Alt) = N_Accept_Alternative then
            Remove_Last_Elmt (Accept_Address
              (Entity (Entry_Direct_Name (Accept_Statement (Alt)))));
         end if;

         Next (Alt);
      end loop;

   end Expand_N_Selective_Accept;

   --------------------------------------
   -- Expand_N_Single_Task_Declaration --
   --------------------------------------

   --  Single task declarations should never be present after semantic
   --  analysis, since we expect them to be replaced by a declaration of
   --  an anonymous task type, followed by a declaration of the task
   --  object. We include this routine to make sure that is happening!

   procedure Expand_N_Single_Task_Declaration (N : Node_Id) is
   begin
      raise Program_Error;
   end Expand_N_Single_Task_Declaration;

   ------------------------
   -- Expand_N_Task_Body --
   ------------------------

   --  Given a task body

   --    task body tname is
   --       <declarations>
   --    begin
   --       <statements>
   --    end x;

   --  This expansion routine converts it into a procedure and sets the
   --  elaboration flag for the procedure to true, to represent the fact
   --  that the task body is now elaborated:

   --    procedure tnameB (_Task : access tnameV) is
   --       discriminal : dtype renames _Task.discriminant;
   --
   --       procedure _clean is
   --       begin
   --          Abort_Defer.all;
   --          Complete_Task;
   --          Abort_Undefer.all;
   --          return;
   --       end _clean;
   --    begin
   --       Abort_Undefer.all;
   --       <declarations>
   --       System.Task_Stages.Complete_Activation;
   --       <statements>
   --    at end
   --       _clean;
   --    end tnameB;

   --    tnameE := True;

   --  In addition, if the task body is an activator, then a call to
   --  activate tasks is added at the start of the statements, before
   --  the call to Complete_Activation, and if in addition the task is
   --  a master then it must be established as a master. These calls are
   --  inserted and analyzed in Expand_Cleanup_Actions, when the
   --  Handled_Sequence_Of_Statements is expanded.

   --  There is one discriminal declaration line generated for each
   --  discriminant that is present to provide an easy reference point
   --  for discriminant references inside the body (see Exp_Ch2.Expand_Name).

   --  Note on relationship to GNARLI definition. In the GNARLI definition,
   --  task body procedures have a profile (Arg : System.Address). That is
   --  needed because GNARLI has to use the same access-to-subprogram type
   --  for all task types. We depend here on knowing that in GNAT, passing
   --  an address argument by value is identical to passing a record value
   --  by access (in either case a single pointer is passed), so even though
   --  this procedure has the wrong profile. In fact it's all OK, since the
   --  callings sequence is identical.

   procedure Expand_N_Task_Body (N : Node_Id) is
      Loc   : constant Source_Ptr := Sloc (N);
      Ttyp  : constant Entity_Id  := Corresponding_Spec (N);
      Call  : Node_Id;
      New_N : Node_Id;

   begin
      --  Do not attempt expansion if in no run time mode

      if No_Run_Time
        and then not Restricted_Profile
      then
         Disallow_In_No_Run_Time_Mode (N);
         return;
      end if;

      --  Here we start the expansion by generating discriminal declarations

      Add_Discriminal_Declarations (Declarations (N), Ttyp, Name_uTask, Loc);

      --  Add a call to Abort_Undefer at the very beginning of the task
      --  body since this body is called with abort still deferred.

      if Abort_Allowed then
         Call := Build_Runtime_Call (Loc, RE_Abort_Undefer);
         Insert_Before
           (First (Statements (Handled_Statement_Sequence (N))), Call);
         Analyze (Call);
      end if;

      --  The statement part has already been protected with an at_end and
      --  cleanup actions. The call to Complete_Activation must be placed
      --  at the head of the sequence of statements of that block. The
      --  declarations have been merged in this sequence of statements but
      --  the first real statement is accessible from the First_Real_Statement
      --  field (which was set for exactly this purpose).

      if Restricted_Profile then
         Call := Build_Runtime_Call (Loc, RE_Complete_Restricted_Activation);
      else
         Call := Build_Runtime_Call (Loc, RE_Complete_Activation);
      end if;

      Insert_Before
        (First_Real_Statement (Handled_Statement_Sequence (N)), Call);
      Analyze (Call);

      New_N :=
        Make_Subprogram_Body (Loc,
          Specification => Build_Task_Proc_Specification (Ttyp),
          Declarations  => Declarations (N),
          Handled_Statement_Sequence => Handled_Statement_Sequence (N));

      --  If the task contains generic instantiations, cleanup actions
      --  are delayed until after instantiation. Transfer the activation
      --  chain to the subprogram, to insure that the activation call is
      --  properly generated. It the task body contains inner tasks, indicate
      --  that the subprogram is a task master.

      if Delay_Cleanups (Ttyp) then
         Set_Activation_Chain_Entity (New_N, Activation_Chain_Entity (N));
         Set_Is_Task_Master  (New_N, Is_Task_Master (N));
      end if;

      Rewrite (N, New_N);
      Analyze (N);

      --  Set elaboration flag immediately after task body. If the body
      --  is a subunit, the flag is set in  the declarative part that
      --  contains the stub.

      if Nkind (Parent (N)) /= N_Subunit then
         Insert_After (N,
           Make_Assignment_Statement (Loc,
             Name =>
               Make_Identifier (Loc, New_External_Name (Chars (Ttyp), 'E')),
             Expression => New_Reference_To (Standard_True, Loc)));
      end if;
   end Expand_N_Task_Body;

   ------------------------------------
   -- Expand_N_Task_Type_Declaration --
   ------------------------------------

   --  We have several things to do. First we must create a Boolean flag used
   --  to mark if the body is elaborated yet. This variable gets set to True
   --  when the body of the task is elaborated (we can't rely on the normal
   --  ABE mechanism for the task body, since we need to pass an access to
   --  this elaboration boolean to the runtime routines).

   --    taskE : aliased Boolean := False;

   --  Next a variable is declared to hold the task stack size (either
   --  the default : Unspecified_Size, or a value that is set by a pragma
   --  Storage_Size). If the value of the pragma Storage_Size is static, then
   --  the variable is initialized with this value:

   --    taskZ : Size_Type := Unspecified_Size;
   --  or
   --    taskZ : Size_Type := Size_Type (size_expression);

   --  Next we create a corresponding record type declaration used to represent
   --  values of this task. The general form of this type declaration is

   --    type taskV (discriminants) is record
   --      _Task_Id     : Task_Id;
   --      entry_family : array (bounds) of Void;
   --      _Priority    : Integer         := priority_expression;
   --      _Size        : Size_Type       := Size_Type (size_expression);
   --      _Task_Info   : Task_Info_Type  := task_info_expression;
   --      _Task_Name   : Task_Image_Type := new String'(task_name_expression);
   --    end record;

   --  The discriminants are present only if the corresponding task type has
   --  discriminants, and they exactly mirror the task type discriminants.

   --  The Id field is always present. It contains the Task_Id value, as
   --  set by the call to Create_Task. Note that although the task is
   --  limited, the task value record type is not limited, so there is no
   --  problem in passing this field as an out parameter to Create_Task.

   --  One entry_family component is present for each entry family in the
   --  task definition. The bounds correspond to the bounds of the entry
   --  family (which may depend on discriminants). The element type is
   --  void, since we only need the bounds information for determining
   --  the entry index. Note that the use of an anonymous array would
   --  normally be illegal in this context, but this is a parser check,
   --  and the semantics is quite prepared to handle such a case.

   --  The _Size field is present only if a Storage_Size pragma appears in
   --  the task definition. The expression captures the argument that was
   --  present in the pragma, and is used to override the task stack size
   --  otherwise associated with the task type.

   --  The _Priority field is present only if a Priority or Interrupt_Priority
   --  pragma appears in the task definition. The expression captures the
   --  argument that was present in the pragma, and is used to provide
   --  the Size parameter to the call to Create_Task.

   --  The _Task_Info field is present only if a Task_Info pragma appears in
   --  the task definition. The expression captures the argument that was
   --  present in the pragma, and is used to provide the Task_Image parameter
   --  to the call to Create_Task.

   --  The _Task_Name field is present only if a Task_Name pragma appears in
   --  the task definition. The expression captures the argument that was
   --  present in the pragma, and is used to provide the Task_Id parameter
   --  to the call to Create_Task.

   --  When a task is declared, an instance of the task value record is
   --  created. The elaboration of this declaration creates the correct
   --  bounds for the entry families, and also evaluates the size, priority,
   --  and task_Info expressions if needed. The initialization routine for
   --  the task type itself then calls Create_Task with appropriate
   --  parameters to initialize the value of the Task_Id field.

   --  Note: the address of this record is passed as the "Discriminants"
   --  parameter for Create_Task. Since Create_Task merely passes this onto
   --  the body procedure, it does not matter that it does not quite match
   --  the GNARLI model of what is being passed (the record contains more
   --  than just the discriminants, but the discriminants can be found from
   --  the record value).

   --  The Entity_Id for this created record type is placed in the
   --  Corresponding_Record_Type field of the associated task type entity.

   --  Next we create a procedure specification for the task body procedure:

   --    procedure taskB (_Task : access taskV);

   --  Note that this must come after the record type declaration, since
   --  the spec refers to this type. It turns out that the initialization
   --  procedure for the value type references the task body spec, but that's
   --  fine, since it won't be generated till the freeze point for the type,
   --  which is certainly after the task body spec declaration.

   --  Finally, we set the task index value field of the entry attribute in
   --  the case of a simple entry.

   procedure Expand_N_Task_Type_Declaration (N : Node_Id) is
      Loc       : constant Source_Ptr := Sloc (N);
      Tasktyp   : constant Entity_Id  := Etype (Defining_Identifier (N));
      Tasknm    : constant Name_Id    := Chars (Tasktyp);
      Taskdef   : constant Node_Id    := Task_Definition (N);

      Proc_Spec : Node_Id;
      Rec_Decl  : Node_Id;
      Rec_Ent   : Entity_Id;
      Cdecls    : List_Id;
      Elab_Decl : Node_Id;
      Size_Decl : Node_Id;
      Body_Decl : Node_Id;

   begin
      --  Do not attempt expansion if in no run time mode

      if No_Run_Time
        and then not Restricted_Profile
      then
         Disallow_In_No_Run_Time_Mode (N);
         return;

      --  If already expanded, nothing to do

      elsif Present (Corresponding_Record_Type (Tasktyp)) then
         return;
      end if;

      --  Here we will do the expansion

      Rec_Decl := Build_Corresponding_Record (N, Tasktyp, Loc);
      Rec_Ent  := Defining_Identifier (Rec_Decl);
      Cdecls   := Component_Items (Component_List
                                     (Type_Definition (Rec_Decl)));

      Qualify_Entity_Names (N);

      --  First create the elaboration variable

      Elab_Decl :=
        Make_Object_Declaration (Loc,
          Defining_Identifier =>
            Make_Defining_Identifier (Sloc (Tasktyp),
              Chars => New_External_Name (Tasknm, 'E')),
          Aliased_Present      => True,
          Object_Definition    => New_Reference_To (Standard_Boolean, Loc),
          Expression           => New_Reference_To (Standard_False, Loc));
      Insert_After (N, Elab_Decl);

      --  Next create the declaration of the size variable (tasknmZ)

      Set_Storage_Size_Variable (Tasktyp,
        Make_Defining_Identifier (Sloc (Tasktyp),
          Chars => New_External_Name (Tasknm, 'Z')));

      if Present (Taskdef) and then Has_Storage_Size_Pragma (Taskdef) and then
        Is_Static_Expression (Expression (First (
          Pragma_Argument_Associations (Find_Task_Or_Protected_Pragma (
            Taskdef, Name_Storage_Size)))))
      then
         Size_Decl :=
           Make_Object_Declaration (Loc,
             Defining_Identifier => Storage_Size_Variable (Tasktyp),
             Object_Definition => New_Reference_To (RTE (RE_Size_Type), Loc),
             Expression =>
               Convert_To (RTE (RE_Size_Type),
                 Relocate_Node (
                   Expression (First (
                     Pragma_Argument_Associations (
                       Find_Task_Or_Protected_Pragma
                         (Taskdef, Name_Storage_Size)))))));

      else
         Size_Decl :=
           Make_Object_Declaration (Loc,
             Defining_Identifier => Storage_Size_Variable (Tasktyp),
             Object_Definition => New_Reference_To (RTE (RE_Size_Type), Loc),
             Expression => New_Reference_To (RTE (RE_Unspecified_Size), Loc));
      end if;

      Insert_After (Elab_Decl, Size_Decl);

      --  Next build the rest of the corresponding record declaration.
      --  This is done last, since the corresponding record initialization
      --  procedure will reference the previously created entities.

      --  Fill in the component declarations. First the _Task_Id field.

      Append_To (Cdecls,
        Make_Component_Declaration (Loc,
          Defining_Identifier =>
            Make_Defining_Identifier (Loc, Name_uTask_Id),
          Subtype_Indication => New_Reference_To (RTE (RO_ST_Task_ID), Loc)));

      --  Add components for entry families

      Collect_Entry_Families (Loc, Cdecls, Size_Decl, Tasktyp);

      --  Add the _Priority component if a Priority pragma is present

      if Present (Taskdef) and then Has_Priority_Pragma (Taskdef) then
         Append_To (Cdecls,
           Make_Component_Declaration (Loc,
             Defining_Identifier =>
               Make_Defining_Identifier (Loc, Name_uPriority),
             Subtype_Indication => New_Reference_To (Standard_Integer, Loc),
             Expression => New_Copy (
               Expression (First (
                 Pragma_Argument_Associations (
                   Find_Task_Or_Protected_Pragma
                     (Taskdef, Name_Priority)))))));
      end if;

      --  Add the _Task_Size component if a Storage_Size pragma is present

      if Present (Taskdef)
        and then Has_Storage_Size_Pragma (Taskdef)
      then
         Append_To (Cdecls,
           Make_Component_Declaration (Loc,
             Defining_Identifier =>
               Make_Defining_Identifier (Loc, Name_uSize),

             Subtype_Indication => New_Reference_To (RTE (RE_Size_Type), Loc),

             Expression =>
               Convert_To (RTE (RE_Size_Type),
                 Relocate_Node (
                   Expression (First (
                     Pragma_Argument_Associations (
                       Find_Task_Or_Protected_Pragma
                         (Taskdef, Name_Storage_Size))))))));
      end if;

      --  Add the _Task_Info component if a Task_Info pragma is present

      if Present (Taskdef) and then Has_Task_Info_Pragma (Taskdef) then
         Append_To (Cdecls,
           Make_Component_Declaration (Loc,
             Defining_Identifier =>
               Make_Defining_Identifier (Loc, Name_uTask_Info),
             Subtype_Indication =>
               New_Reference_To (RTE (RE_Task_Info_Type), Loc),
             Expression => New_Copy (
               Expression (First (
                 Pragma_Argument_Associations (
                   Find_Task_Or_Protected_Pragma
                     (Taskdef, Name_Task_Info)))))));
      end if;

      --  Add the _Task_Name component if a Task_Name pragma is present

      if Present (Taskdef) and then Has_Task_Name_Pragma (Taskdef) then
         Append_To (Cdecls,
           Make_Component_Declaration (Loc,
             Defining_Identifier =>
               Make_Defining_Identifier (Loc, Name_uTask_Info),
             Subtype_Indication =>
               New_Reference_To (RTE (RE_Task_Image_Type), Loc),
             Expression =>
               Make_Allocator (Loc,
                 Expression =>
                   Make_Qualified_Expression (Loc,
                     Subtype_Mark =>
                       New_Occurrence_Of (Standard_String, Loc),
                     Expression =>
                       New_Copy (
                         Expression (First (
                           Pragma_Argument_Associations (
                             Find_Task_Or_Protected_Pragma
                               (Taskdef, Name_Task_Name)))))))));
      end if;

      Insert_After (Size_Decl, Rec_Decl);

      --  Analyze the record declaration immediately after construction,
      --  because the initialization procedure is needed for single task
      --  declarations before the next entity is analyzed.

      Analyze (Rec_Decl);

      --  Create the declaration of the task body procedure

      Proc_Spec := Build_Task_Proc_Specification (Tasktyp);
      Body_Decl :=
        Make_Subprogram_Declaration (Loc,
          Specification => Proc_Spec);

      Insert_After (Rec_Decl, Body_Decl);

      --  Now we can freeze the corresponding record. This needs manually
      --  freezing, since it is really part of the task type, and the task
      --  type is frozen at this stage. We of course need the initialization
      --  procedure for this corresponding record type and we won't get it
      --  in time if we don't freeze now.

      declare
         L : constant List_Id := Freeze_Entity (Rec_Ent, Loc);

      begin
         if Is_Non_Empty_List (L) then
            Insert_List_After (Body_Decl, L);
         end if;
      end;

      --  Complete the expansion of access types to the current task
      --  type, if any were declared.

      Expand_Previous_Access_Type (Tasktyp);
   end Expand_N_Task_Type_Declaration;

   -------------------------------
   -- Expand_N_Timed_Entry_Call --
   -------------------------------

   --  A timed entry call in normal case is not implemented using ATC
   --  mechanism anymore for efficiency reason.

   --     select
   --        T.E;
   --        S1;
   --     or
   --        Delay D;
   --        S2;
   --     end select;

   --  is expanded as follow:

   --  1) When T.E is a task entry_call;

   --    declare
   --       B : Boolean;
   --       X : Task_Entry_Index := <entry index>;
   --       DX : Duration := To_Duration (D);
   --       M : Delay_Mode := <discriminant>;
   --       P : parms := (parm, parm, parm);

   --    begin
   --       Timed_Protected_Entry_Call (<acceptor-task>, X, P'Address,
   --         DX, M, B);
   --       if B then
   --          S1;
   --       else
   --          S2;
   --       end if;
   --    end;

   --  2) When T.E is a protected entry_call;

   --    declare
   --       B  : Boolean;
   --       X  : Protected_Entry_Index := <entry index>;
   --       DX : Duration := To_Duration (D);
   --       M : Delay_Mode := <discriminant>;
   --       P  : parms := (parm, parm, parm);

   --    begin
   --       Timed_Protected_Entry_Call (<object>'unchecked_access, X,
   --         P'Address, DX, M, B);
   --       if B then
   --          S1;
   --       else
   --          S2;
   --       end if;
   --    end;

   procedure Expand_N_Timed_Entry_Call (N : Node_Id) is
      Loc : constant Source_Ptr := Sloc (N);

      E_Call  : Node_Id :=
                  Entry_Call_Statement (Entry_Call_Alternative (N));
      E_Stats : constant List_Id :=
                  Statements (Entry_Call_Alternative (N));
      D_Stat  : constant Node_Id :=
                  Delay_Statement (Delay_Alternative (N));
      D_Stats : constant List_Id :=
                  Statements (Delay_Alternative (N));

      Stmts : List_Id;
      Stmt  : Node_Id;
      Parms : List_Id;
      Parm  : Node_Id;

      Concval : Node_Id;
      Ename   : Node_Id;
      Index   : Node_Id;

      Decls : List_Id;
      Disc  : Node_Id;
      Conv  : Node_Id;
      B     : Entity_Id;
      D     : Entity_Id;
      Dtyp  : Entity_Id;
      M     : Entity_Id;

      Call  : Node_Id;
      Dummy : Node_Id;

   begin
      --  The arguments in the call may require dynamic allocation, and the
      --  call statement may have been transformed into a block. The block
      --  may contain additional declarations for internal entities, and the
      --  original call is found by sequential search.

      if Nkind (E_Call) = N_Block_Statement then
         E_Call := First (Statements (Handled_Statement_Sequence (E_Call)));

         while Nkind (E_Call) /= N_Procedure_Call_Statement
           and then Nkind (E_Call) /= N_Entry_Call_Statement
         loop
            Next (E_Call);
         end loop;
      end if;

      --  Build an entry call using Simple_Entry_Call. We will use this as the
      --  base for creating appropriate calls.

      Extract_Entry (E_Call, Concval, Ename, Index);
      Build_Simple_Entry_Call (E_Call, Concval, Ename, Index);

      Stmts := Statements (Handled_Statement_Sequence (E_Call));
      Decls := Declarations (E_Call);

      if No (Decls) then
         Decls := New_List;
      end if;

      Dtyp := Base_Type (Etype (Expression (D_Stat)));

      --  Use the type of the delay expression (Calendar or Real_Time)
      --  to generate the appropriate conversion.

      if Nkind (D_Stat) = N_Delay_Relative_Statement then
         Disc := Make_Integer_Literal (Loc, 0);
         Conv := Relocate_Node (Expression (D_Stat));

      elsif Is_RTE (Dtyp, RO_CA_Time) then
         Disc := Make_Integer_Literal (Loc, 1);
         Conv := Make_Function_Call (Loc,
           New_Reference_To (RTE (RO_CA_To_Duration), Loc),
           New_List (New_Copy (Expression (D_Stat))));

      else pragma Assert (Is_RTE (Dtyp, RO_RT_Time));
         Disc := Make_Integer_Literal (Loc, 2);
         Conv := Make_Function_Call (Loc,
           New_Reference_To (RTE (RO_RT_To_Duration), Loc),
           New_List (New_Copy (Expression (D_Stat))));
      end if;

      --  Create a Duration and a Delay_Mode object used for passing a delay
      --  value

      D := Make_Defining_Identifier (Loc, New_Internal_Name ('D'));
      M := Make_Defining_Identifier (Loc, New_Internal_Name ('M'));

      Append_To (Decls,
        Make_Object_Declaration (Loc,
          Defining_Identifier => D,
          Object_Definition => New_Reference_To (Standard_Duration, Loc)));

      Append_To (Decls,
        Make_Object_Declaration (Loc,
          Defining_Identifier => M,
          Object_Definition => New_Reference_To (Standard_Integer, Loc),
          Expression        => Disc));

      B := Make_Defining_Identifier (Loc, Name_uB);

      --  Create a boolean object used for a return parameter.

      Prepend_To (Decls,
        Make_Object_Declaration (Loc,
          Defining_Identifier => B,
          Object_Definition => New_Reference_To (Standard_Boolean, Loc)));

      Stmt := First (Stmts);

      --  Skip assignments to temporaries created for in-out parameters.
      --  This makes unwarranted assumptions about the shape of the expanded
      --  tree for the call, and should be cleaned up ???

      while Nkind (Stmt) /= N_Procedure_Call_Statement loop
         Next (Stmt);
      end loop;

      --  Do the assignement at this stage only because the evaluation of the
      --  expression must not occur before (see ACVC C97302A).

      Insert_Before (Stmt,
        Make_Assignment_Statement (Loc,
          Name => New_Reference_To (D, Loc),
          Expression => Conv));

      Call := Stmt;

      Parms := Parameter_Associations (Call);

      --  For a protected type, we build a Timed_Protected_Entry_Call

      if Is_Protected_Type (Etype (Concval)) then

         --  Create a new call statement

         Parm := First (Parms);

         while Present (Parm)
           and then not Is_RTE (Etype (Parm), RE_Call_Modes)
         loop
            Next (Parm);
         end loop;

         Dummy := Remove_Next (Next (Parm));

         --  In case some garbage is following the Cancel_Param, remove.

         Dummy := Next (Parm);

         --  Remove the mode of the Protected_Entry_Call call, the
         --  Communication_Block of the Protected_Entry_Call call, and add a
         --  Duration and a Delay_Mode parameter

         pragma Assert (Present (Parm));
         Rewrite (Parm, New_Reference_To (D, Loc));

         Rewrite (Dummy, New_Reference_To (M, Loc));

         --  Add a Boolean flag for successful entry call.

         Append_To (Parms, New_Reference_To (B, Loc));

         if Abort_Allowed
           or else Restrictions (No_Entry_Queue) = False
           or else Number_Entries (Etype (Concval)) > 1
         then
            Rewrite (Call,
              Make_Procedure_Call_Statement (Loc,
                Name =>
                  New_Reference_To (RTE (RE_Timed_Protected_Entry_Call), Loc),
                Parameter_Associations => Parms));

         else
            Parm := First (Parms);

            while Present (Parm)
              and then not Is_RTE (Etype (Parm), RE_Protected_Entry_Index)
            loop
               Next (Parm);
            end loop;

            Remove (Parm);

            Rewrite (Call,
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (
                  RTE (RE_Timed_Protected_Single_Entry_Call), Loc),
                Parameter_Associations => Parms));
         end if;

      --  For the task case, build a Timed_Task_Entry_Call

      else
         --  Create a new call statement

         Append_To (Parms, New_Reference_To (D, Loc));
         Append_To (Parms, New_Reference_To (M, Loc));
         Append_To (Parms, New_Reference_To (B, Loc));

         Rewrite (Call,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Timed_Task_Entry_Call), Loc),
             Parameter_Associations => Parms));

      end if;

      Append_To (Stmts,
        Make_Implicit_If_Statement (N,
          Condition => New_Reference_To (B, Loc),
          Then_Statements => E_Stats,
          Else_Statements => D_Stats));

      Rewrite (N,
        Make_Block_Statement (Loc,
          Declarations => Decls,
          Handled_Statement_Sequence =>
            Make_Handled_Sequence_Of_Statements (Loc, Stmts)));

      Analyze (N);

   end Expand_N_Timed_Entry_Call;

   ----------------------------------------
   -- Expand_Protected_Body_Declarations --
   ----------------------------------------

   --  Part of the expansion of a protected body involves the creation of
   --  a declaration that can be referenced from the statement sequences of
   --  the entry bodies:

   --    A : Address;

   --  This declaration is inserted in the declarations of the service
   --  entries procedure for the protected body, and it is important that
   --  it be inserted before the statements of the entry body statement
   --  sequences are analyzed. Thus it would be too late to create this
   --  declaration in the Expand_N_Protected_Body routine, which is why
   --  there is a separate procedure to be called directly from Sem_Ch9.

   --  Ann is used to hold the address of the record containing the parameters
   --  (see Expand_N_Entry_Call for more details on how this record is built).
   --  References to the parameters do an unchecked conversion of this address
   --  to a pointer to the required record type, and then access the field that
   --  holds the value of the required parameter. The entity for the address
   --  variable is held as the top stack element (i.e. the last element) of the
   --  Accept_Address stack in the corresponding entry entity, and this element
   --  must be set in place  before the statements are processed.

   --  No stack is needed for entry bodies, since they cannot be nested, but
   --  it is kept for consistency between protected and task entries. The
   --  stack will never contain more than one element. There is also only one
   --  such variable for a given protected body, but this is placed on the
   --  Accept_Address stack of all of the entries, again for consistency.

   --  To expand the requeue statement, a label is provided at the end of
   --  the loop in the entry service routine created by the expander (see
   --  Expand_N_Protected_Body for details), so that the statement can be
   --  skipped after the requeue is complete. This label is created during the
   --  expansion of the entry body, which will take place after the expansion
   --  of the requeue statements that it contains, so a placeholder defining
   --  identifier is associated with the task type here.

   --  Another label is provided following case statement created by the
   --  expander. This label is need for implementing return statement from
   --  entry body so that a return can be expanded as a goto to this label.
   --  This label is created during the expansion of the entry body, which
   --  will take place after the expansion of the return statements that it
   --  contains. Therefore, just like the label for expanding requeues, we
   --  need another placeholder for the label.

   procedure Expand_Protected_Body_Declarations
     (N : Node_Id;
      Spec_Id : Entity_Id)
   is
      Op : Node_Id;

   begin
      if Expander_Active then

         --  Associate privals with the first subprogram or entry
         --  body to be expanded. These are used to expand references
         --  to private data objects.

         Op := First_Protected_Operation (Declarations (N));

         if Present (Op) then
            Set_Discriminals (Parent (Spec_Id));
            Set_Privals (Parent (Spec_Id), Op, Sloc (N));
         end if;
      end if;
   end Expand_Protected_Body_Declarations;

   -------------------------
   -- External_Subprogram --
   -------------------------

   function External_Subprogram (E : Entity_Id) return Entity_Id is
      Subp : constant Entity_Id := Protected_Body_Subprogram (E);
      Decl : constant Node_Id   := Unit_Declaration_Node (E);

   begin
      --  If the protected operation is defined in the visible part of the
      --  protected type, or if it is an interrupt handler, the internal and
      --  external subprograms follow each other on the entity chain. If the
      --  operation is defined in the private part of the type, there is no
      --  need for a separate locking version of the operation, and internal
      --  calls use the protected_body_subprogram directly.

      if List_Containing (Decl) = Visible_Declarations (Parent (Decl))
        or else Is_Interrupt_Handler (E)
      then
         return Next_Entity (Subp);
      else
         return (Subp);
      end if;
   end External_Subprogram;

   -------------------
   -- Extract_Entry --
   -------------------

   procedure Extract_Entry
     (N       : Node_Id;
      Concval : out Node_Id;
      Ename   : out Node_Id;
      Index   : out Node_Id)
   is
      Nam : constant Node_Id := Name (N);

   begin
      --  For a simple entry, the name is a selected component, with the
      --  prefix being the task value, and the selector being the entry.

      if Nkind (Nam) = N_Selected_Component then
         Concval := Prefix (Nam);
         Ename   := Selector_Name (Nam);
         Index   := Empty;

         --  For a member of an entry family, the name is an indexed
         --  component where the prefix is a selected component,
         --  whose prefix in turn is the task value, and whose
         --  selector is the entry family. The single expression in
         --  the expressions list of the indexed component is the
         --  subscript for the family.

      else
         pragma Assert (Nkind (Nam) = N_Indexed_Component);
         Concval := Prefix (Prefix (Nam));
         Ename   := Selector_Name (Prefix (Nam));
         Index   := First (Expressions (Nam));
      end if;

   end Extract_Entry;

   -------------------
   -- Family_Offset --
   -------------------

   function Family_Offset
     (Loc  : Source_Ptr;
      Hi   : Node_Id;
      Lo   : Node_Id;
      Ttyp : Entity_Id)
      return Node_Id
   is
      function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id;
      --  If one of the bounds is a reference to a discriminant, replace
      --  with corresponding discriminal of type. Within the body of a task
      --  retrieve the renamed discriminant by simple visibility, using its
      --  generated name. Within a protected object, find the original dis-
      --  criminant and replace it with the discriminal of the current prot-
      --  ected operation.

      ------------------------------
      -- Convert_Discriminant_Ref --
      ------------------------------

      function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id is
         Loc : constant Source_Ptr := Sloc (Bound);
         B   : Node_Id;
         D   : Entity_Id;

      begin
         if Is_Entity_Name (Bound)
           and then Ekind (Entity (Bound)) = E_Discriminant
         then
            if Is_Task_Type (Ttyp)
              and then Has_Completion (Ttyp)
            then
               B := Make_Identifier (Loc, Chars (Entity (Bound)));
               Find_Direct_Name (B);

            elsif Is_Protected_Type (Ttyp) then
               D := First_Discriminant (Ttyp);

               while Chars (D) /= Chars (Entity (Bound)) loop
                  Next_Discriminant (D);
               end loop;

               B := New_Reference_To  (Discriminal (D), Loc);

            else
               B := New_Reference_To (Discriminal (Entity (Bound)), Loc);
            end if;

         elsif Nkind (Bound) = N_Attribute_Reference then
            return Bound;

         else
            B := New_Copy_Tree (Bound);
         end if;

         return
           Make_Attribute_Reference (Loc,
             Attribute_Name => Name_Pos,
             Prefix => New_Occurrence_Of (Etype (Bound), Loc),
             Expressions    => New_List (B));
      end Convert_Discriminant_Ref;

   --  Start of processing for Family_Offset

   begin
      return
        Make_Op_Subtract (Loc,
          Left_Opnd  => Convert_Discriminant_Ref (Hi),
          Right_Opnd => Convert_Discriminant_Ref (Lo));

   end Family_Offset;

   -----------------
   -- Family_Size --
   -----------------

   function Family_Size
     (Loc  : Source_Ptr;
      Hi   : Node_Id;
      Lo   : Node_Id;
      Ttyp : Entity_Id)
      return Node_Id
   is
      Ityp : Entity_Id;

   begin
      if Is_Task_Type (Ttyp) then
         Ityp := RTE (RE_Task_Entry_Index);
      else
         Ityp := RTE (RE_Protected_Entry_Index);
      end if;

      return
        Make_Attribute_Reference (Loc,
          Prefix         => New_Reference_To (Ityp, Loc),
          Attribute_Name => Name_Max,
          Expressions    => New_List (
            Make_Op_Add (Loc,
              Left_Opnd  =>
                Family_Offset (Loc, Hi, Lo, Ttyp),
              Right_Opnd =>
                Make_Integer_Literal (Loc, 1)),
            Make_Integer_Literal (Loc, 0)));
   end Family_Size;

   -----------------------------------
   -- Find_Task_Or_Protected_Pragma --
   -----------------------------------

   function Find_Task_Or_Protected_Pragma
     (T    : Node_Id;
      P    : Name_Id)
      return Node_Id
   is
      N : Node_Id;

   begin
      N := First (Visible_Declarations (T));

      while Present (N) loop
         if Nkind (N) = N_Pragma then
            if Chars (N) = P then
               return N;

            elsif P = Name_Priority
              and then Chars (N) = Name_Interrupt_Priority
            then
               return N;

            else
               Next (N);
            end if;

         else
            Next (N);
         end if;
      end loop;

      N := First (Private_Declarations (T));

      while Present (N) loop
         if Nkind (N) = N_Pragma then
            if  Chars (N) = P then
               return N;

            elsif P = Name_Priority
              and then Chars (N) = Name_Interrupt_Priority
            then
               return N;

            else
               Next (N);
            end if;

         else
            Next (N);
         end if;
      end loop;

      raise Program_Error;
   end Find_Task_Or_Protected_Pragma;

   -------------------------------
   -- First_Protected_Operation --
   -------------------------------

   function First_Protected_Operation (D : List_Id) return Node_Id is
      First_Op : Node_Id;

   begin
      First_Op := First (D);
      while Present (First_Op)
        and then Nkind (First_Op) /= N_Subprogram_Body
        and then Nkind (First_Op) /= N_Entry_Body
      loop
         Next (First_Op);
      end loop;

      return First_Op;
   end First_Protected_Operation;

   --------------------------------
   -- Index_Constant_Declaration --
   --------------------------------

   function Index_Constant_Declaration
     (N        : Node_Id;
      Index_Id : Entity_Id;
      Prot     : Entity_Id)
      return     List_Id
   is
      Loc       : constant Source_Ptr := Sloc (N);
      Decls     : List_Id             := New_List;
      Index_Con : constant Entity_Id  := Entry_Index_Constant (Index_Id);
      Index_Typ : Entity_Id;

      Hi : Node_Id := Type_High_Bound (Etype (Index_Id));
      Lo : Node_Id := Type_Low_Bound  (Etype (Index_Id));

      function Replace_Discriminant (Bound : Node_Id) return Node_Id;
      --  The bounds of the entry index may depend on discriminants, so
      --  each declaration of an entry_index_constant must have its own
      --  subtype declaration, using the local renaming of the object discri-
      --  minant.

      --------------------------
      -- Replace_Discriminant --
      --------------------------

      function Replace_Discriminant (Bound : Node_Id) return Node_Id is
      begin
         if Nkind (Bound) = N_Identifier
           and then Ekind (Entity (Bound)) = E_Constant
           and then Present (Discriminal_Link (Entity (Bound)))
         then
            return Make_Identifier (Loc, Chars (Entity (Bound)));
         else
            return Duplicate_Subexpr (Bound);
         end if;
      end Replace_Discriminant;

   --  Start of processing for Index_Constant_Declaration

   begin
      Set_Discriminal_Link (Index_Con, Index_Id);

      if Is_Entity_Name (
        Original_Node (Discrete_Subtype_Definition (Parent (Index_Id))))
      then
         --  Simple case: entry family is given by a subtype mark, and index
         --  constant has the same type, no replacement needed.

         Index_Typ := Etype (Index_Id);

      else
         Hi := Replace_Discriminant (Hi);
         Lo := Replace_Discriminant (Lo);

         Index_Typ := Make_Defining_Identifier (Loc, New_Internal_Name ('I'));

         Append (
           Make_Subtype_Declaration (Loc,
             Defining_Identifier => Index_Typ,
             Subtype_Indication =>
               Make_Subtype_Indication (Loc,
                 Subtype_Mark =>
                   New_Occurrence_Of (Base_Type (Etype (Index_Id)), Loc),
                 Constraint =>
                   Make_Range_Constraint (Loc,
                     Range_Expression => Make_Range (Loc, Lo, Hi)))),
           Decls);

      end if;

      Append (
        Make_Object_Declaration (Loc,
          Defining_Identifier => Index_Con,
          Constant_Present => True,
          Object_Definition => New_Occurrence_Of (Index_Typ, Loc),

          Expression =>
            Make_Attribute_Reference (Loc,
              Prefix => New_Reference_To (Index_Typ, Loc),
              Attribute_Name => Name_Val,

              Expressions => New_List (

                Make_Op_Add (Loc,
                  Left_Opnd =>
                    Make_Op_Subtract (Loc,
                      Left_Opnd => Make_Identifier (Loc, Name_uE),
                      Right_Opnd =>
                        Entry_Index_Expression (Loc,
                          Defining_Identifier (N), Empty, Prot)),

                  Right_Opnd =>
                    Make_Attribute_Reference (Loc,
                      Prefix => New_Reference_To (Index_Typ, Loc),
                      Attribute_Name => Name_Pos,
                      Expressions => New_List (
                        Make_Attribute_Reference (Loc,
                          Prefix => New_Reference_To (Index_Typ, Loc),
                    Attribute_Name => Name_First))))))),
      Decls);

      return Decls;
   end Index_Constant_Declaration;

   --------------------------------
   -- Make_Initialize_Protection --
   --------------------------------

   function Make_Initialize_Protection
     (Protect_Rec : Entity_Id)
      return        List_Id
   is
      Loc    : constant Source_Ptr := Sloc (Protect_Rec);
      P_Arr  : Entity_Id;
      Pdef   : Node_Id;
      Pdec   : Node_Id;
      Ptyp   : Node_Id;
      Pnam   : Name_Id;
      Args   : List_Id;
      L      : List_Id := New_List;

   begin
      --  We may need two calls to properly initialize the object, one
      --  to Initialize_Protection, and possibly one to Install_Handlers
      --  if we have a pragma Attach_Handler.

      Ptyp := Corresponding_Concurrent_Type (Protect_Rec);
      Pnam := Chars (Ptyp);

      --  Get protected declaration. In the case of a task type declaration,
      --  this is simply the parent of the protected type entity.
      --  In the single protected object
      --  declaration, this parent will be the implicit type, and we can find
      --  the corresponding single protected object declaration by
      --  searching forward in the declaration list in the tree.
      --  ??? I am not sure that the test for N_Single_Protected_Declaration
      --      is needed here. Nodes of this type should have been removed
      --      during semantic analysis.

      Pdec := Parent (Ptyp);

      while Nkind (Pdec) /= N_Protected_Type_Declaration
        and then Nkind (Pdec) /= N_Single_Protected_Declaration
      loop
         Next (Pdec);
      end loop;

      --  Now we can find the object definition from this declaration

      Pdef := Protected_Definition (Pdec);

      --  Build the parameter list for the call. Note that _Init is the name
      --  of the formal for the object to be initialized, which is the task
      --  value record itself.

      Args := New_List;

      --  Object parameter. This is a pointer to the object of type
      --  Protection used by the GNARL to control the protected object.

      Append_To (Args,
        Make_Attribute_Reference (Loc,
          Prefix =>
            Make_Selected_Component (Loc,
              Prefix => Make_Identifier (Loc, Name_uInit),
              Selector_Name => Make_Identifier (Loc, Name_uObject)),
          Attribute_Name => Name_Unchecked_Access));

      --  Priority parameter. Set to Unspecified_Priority unless there is a
      --  priority pragma, in which case we take the value from the pragma,
      --  or there is an interrupt pragma and no priority pragma, and we
      --  set the ceiling to Interrupt_Priority'Last, an implementation-
      --  defined value, see D.3(10).

      if Present (Pdef)
        and then Has_Priority_Pragma (Pdef)
      then
         Append_To (Args,
           Duplicate_Subexpr (Expression (First (Pragma_Argument_Associations
             (Find_Task_Or_Protected_Pragma (Pdef, Name_Priority))))));

      elsif Has_Interrupt_Handler (Ptyp)
        or else Has_Attach_Handler (Ptyp)
      then
         --  When no priority is specified but an xx_Handler pragma is,
         --  we default to System.Interrupts.Default_Interrupt_Priority,
         --  see D.3(10).

         Append_To (Args,
           New_Reference_To (RTE (RE_Default_Interrupt_Priority), Loc));

      else
         Append_To (Args,
           New_Reference_To (RTE (RE_Unspecified_Priority), Loc));
      end if;

      if Has_Entries (Ptyp)
        or else Has_Interrupt_Handler (Ptyp)
        or else Has_Attach_Handler (Ptyp)
      then
         --  Compiler_Info parameter. This parameter allows entry body
         --  procedures and barrier functions to be called from the runtime.
         --  It is a pointer to the record generated by the compiler to
         --  represent the protected object.

         Append_To (Args,
            Make_Attribute_Reference (Loc,
              Prefix => Make_Identifier (Loc, Name_uInit),
              Attribute_Name => Name_Address));

         if Has_Entries (Ptyp) then
            --  Entry_Bodies parameter. This is a pointer to an array of
            --  pointers to the entry body procedures and barrier functions
            --  of the object. If the protected type has no entries this
            --  object will not exist; in this case, pass a null.

            P_Arr := Entry_Bodies_Array (Ptyp);

            Append_To (Args,
              Make_Attribute_Reference (Loc,
                Prefix => New_Reference_To (P_Arr, Loc),
                Attribute_Name => Name_Unrestricted_Access));

            if Abort_Allowed
              or else Restrictions (No_Entry_Queue) = False
              or else Number_Entries (Ptyp) > 1
            then
               --  Find index mapping function (clumsy but ok for now).

               while Ekind (P_Arr) /= E_Function loop
                  Next_Entity (P_Arr);
               end loop;

               Append_To (Args,
                  Make_Attribute_Reference (Loc,
                    Prefix =>
                      New_Reference_To (P_Arr, Loc),
                    Attribute_Name => Name_Unrestricted_Access));
            end if;

         else
            Append_To (Args, Make_Null (Loc));
            Append_To (Args, Make_Null (Loc));
         end if;

         if Abort_Allowed
           or else Restrictions (No_Entry_Queue) = False
           or else Number_Entries (Ptyp) > 1
         then
            Append_To (L,
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (
                  RTE (RE_Initialize_Protection_Entries), Loc),
                Parameter_Associations => Args));

         else
            Append_To (L,
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (
                  RTE (RE_Initialize_Protection_Entry), Loc),
                Parameter_Associations => Args));
         end if;

      else
         Append_To (L,
           Make_Procedure_Call_Statement (Loc,
             Name => New_Reference_To (RTE (RE_Initialize_Protection), Loc),
             Parameter_Associations => Args));
      end if;

      if Has_Attach_Handler (Ptyp) then

         --  We have a list of N Attach_Handler (ProcI, ExprI),
         --  and we have to make the following call:
         --  Install_Handlers (_object,
         --    ((Expr1, Proc1'access), ...., (ExprN, ProcN'access));

         declare
            Args  : List_Id := New_List;
            Table : List_Id := New_List;
            Ritem : Node_Id := First_Rep_Item (Ptyp);

         begin
            --  Appends the _object argument

            Append_To (Args,
              Make_Attribute_Reference (Loc,
                Prefix =>
                  Make_Selected_Component (Loc,
                    Prefix => Make_Identifier (Loc, Name_uInit),
                    Selector_Name => Make_Identifier (Loc, Name_uObject)),
                Attribute_Name => Name_Unchecked_Access));

            --  Build the Attach_Handler table argument

            while Present (Ritem) loop
               if Nkind (Ritem) = N_Pragma
                 and then Chars (Ritem) = Name_Attach_Handler
               then
                  declare
                     Handler   : Node_Id :=
                       First (Pragma_Argument_Associations (Ritem));
                     Interrupt : Node_Id :=
                       Next (Handler);

                  begin
                     Append_To (Table,
                       Make_Aggregate (Loc, Expressions => New_List (
                         Duplicate_Subexpr (Expression (Interrupt)),
                         Make_Attribute_Reference (Loc,
                           Prefix => Make_Selected_Component (Loc,
                              Make_Identifier (Loc, Name_uInit),
                              Duplicate_Subexpr (Expression (Handler))),
                           Attribute_Name => Name_Access))));
                  end;
               end if;

               Next_Rep_Item (Ritem);
            end loop;

            --  Appends the table argument we just built.
            Append_To (Args, Make_Aggregate (Loc, Table));

            --  Appends the Install_Handler call to the statements.
            Append_To (L,
              Make_Procedure_Call_Statement (Loc,
                Name => New_Reference_To (RTE (RE_Install_Handlers), Loc),
                Parameter_Associations => Args));
         end;
      end if;

      return L;
   end Make_Initialize_Protection;

   ---------------------------
   -- Make_Task_Create_Call --
   ---------------------------

   function Make_Task_Create_Call (Task_Rec : Entity_Id) return Node_Id is
      Loc    : constant Source_Ptr := Sloc (Task_Rec);
      Name   : Node_Id;
      Tdef   : Node_Id;
      Tdec   : Node_Id;
      Ttyp   : Node_Id;
      Tnam   : Name_Id;
      Args   : List_Id;
      Ecount : Node_Id;

   begin
      Ttyp := Corresponding_Concurrent_Type (Task_Rec);
      Tnam := Chars (Ttyp);

      --  Get task declaration. In the case of a task type declaration, this
      --  is simply the parent of the task type entity. In the single task
      --  declaration, this parent will be the implicit type, and we can find
      --  the corresponding single task declaration by searching forward in
      --  the declaration list in the tree.
      --  ??? I am not sure that the test for N_Single_Task_Declaration
      --      is needed here. Nodes of this type should have been removed
      --      during semantic analysis.

      Tdec := Parent (Ttyp);

      while Nkind (Tdec) /= N_Task_Type_Declaration
        and then Nkind (Tdec) /= N_Single_Task_Declaration
      loop
         Next (Tdec);
      end loop;

      --  Now we can find the task definition from this declaration

      Tdef := Task_Definition (Tdec);

      --  Build the parameter list for the call. Note that _Init is the name
      --  of the formal for the object to be initialized, which is the task
      --  value record itself.

      Args := New_List;

      --  Priority parameter. Set to Unspecified_Priority unless there is a
      --  priority pragma, in which case we take the value from the pragma.

      if Present (Tdef)
        and then Has_Priority_Pragma (Tdef)
      then
         Append_To (Args,
           Make_Selected_Component (Loc,
             Prefix => Make_Identifier (Loc, Name_uInit),
             Selector_Name => Make_Identifier (Loc, Name_uPriority)));

      else
         Append_To (Args,
           New_Reference_To (RTE (RE_Unspecified_Priority), Loc));
      end if;

      --  Size parameter. If no Storage_Size pragma is present, then
      --  the size is taken from the taskZ variable for the type, which
      --  is either Unspecified_Size, or has been reset by the use of
      --  a Storage_Size attribute definition clause. If a pragma is
      --  present, then the size is taken from the _Size field of the
      --  task value record, which was set from the pragma value.

      if Present (Tdef)
        and then Has_Storage_Size_Pragma (Tdef)
      then
         Append_To (Args,
           Make_Selected_Component (Loc,
             Prefix => Make_Identifier (Loc, Name_uInit),
             Selector_Name => Make_Identifier (Loc, Name_uSize)));

      else
         Append_To (Args,
           New_Reference_To (Storage_Size_Variable (Ttyp), Loc));
      end if;

      --  Task_Info parameter. Set to Unspecified_Task_Info unless there is a
      --  Task_Info pragma, in which case we take the value from the pragma.

      if Present (Tdef)
        and then Has_Task_Info_Pragma (Tdef)
      then
         Append_To (Args,
           Make_Selected_Component (Loc,
             Prefix => Make_Identifier (Loc, Name_uInit),
             Selector_Name => Make_Identifier (Loc, Name_uTask_Info)));

      else
         Append_To (Args,
           New_Reference_To (RTE (RE_Unspecified_Task_Info), Loc));
      end if;

      if not Restricted_Profile then

         --  Number of entries. This is an expression of the form:
         --
         --    n + _Init.a'Length + _Init.a'B'Length + ...
         --
         --  where a,b... are the entry family names for the task definition

         Ecount := Build_Entry_Count_Expression (
           Ttyp,
           Component_Items (Component_List (
             Type_Definition (Parent (
               Corresponding_Record_Type (Ttyp))))),
           Loc);
         Append_To (Args, Ecount);

         --  Master parameter. This is a reference to the _Master parameter of
         --  the initialization procedure, except in the case of the pragma
         --  Restrictions (No_Task_Hierarchy) where the value is fixed to 3.
         --  See comments in System.Tasking.Initialization.Init_RTS for the
         --  value 3.

         if Restrictions (No_Task_Hierarchy) = False then
            Append_To (Args, Make_Identifier (Loc, Name_uMaster));
         else
            Append_To (Args, Make_Integer_Literal (Loc, 3));
         end if;
      end if;

      --  State parameter. This is a pointer to the task body procedure. The
      --  required value is obtained by taking the address of the task body
      --  procedure and converting it (with an unchecked conversion) to the
      --  type required by the task kernel. For further details, see the
      --  description of Expand_Task_Body

      Append_To (Args,
        Unchecked_Convert_To (RTE (RE_Task_Procedure_Access),
          Make_Attribute_Reference (Loc,
            Prefix =>
              New_Occurrence_Of (Get_Task_Body_Procedure (Ttyp), Loc),
            Attribute_Name => Name_Address)));

      --  Discriminants parameter. This is just the address of the task
      --  value record itself (which contains the discriminant values

      Append_To (Args,
        Make_Attribute_Reference (Loc,
          Prefix => Make_Identifier (Loc, Name_uInit),
          Attribute_Name => Name_Address));

      --  Elaborated parameter. This is an access to the elaboration Boolean

      Append_To (Args,
        Make_Attribute_Reference (Loc,
          Prefix => Make_Identifier (Loc, New_External_Name (Tnam, 'E')),
          Attribute_Name => Name_Unchecked_Access));

      --  Chain parameter. This is a reference to the _Chain parameter of
      --  the initialization procedure.

      Append_To (Args, Make_Identifier (Loc, Name_uChain));

      --  Task name parameter. Take this from the _Task_Info parameter to the
      --  init call unless there is a Task_Name pragma, in which case we take
      --  the value from the pragma.

      if Present (Tdef)
        and then Has_Task_Name_Pragma (Tdef)
      then
         Append_To (Args,
           Make_Selected_Component (Loc,
             Prefix => Make_Identifier (Loc, Name_uInit),
             Selector_Name => Make_Identifier (Loc, Name_uTask_Info)));

      else
         Append_To (Args, Make_Identifier (Loc, Name_uTask_Id));
      end if;

      --  Created_Task parameter. This is the _Task_Id field of the task
      --  record value

      Append_To (Args,
        Make_Selected_Component (Loc,
          Prefix => Make_Identifier (Loc, Name_uInit),
          Selector_Name => Make_Identifier (Loc, Name_uTask_Id)));

      if Restricted_Profile then
         Name := New_Reference_To (RTE (RE_Create_Restricted_Task), Loc);
      else
         Name := New_Reference_To (RTE (RE_Create_Task), Loc);
      end if;

      return Make_Procedure_Call_Statement (Loc,
        Name => Name, Parameter_Associations => Args);
   end Make_Task_Create_Call;

   ------------------------------
   -- Next_Protected_Operation --
   ------------------------------

   function Next_Protected_Operation (N : Node_Id) return Node_Id is
      Next_Op : Node_Id;

   begin
      Next_Op := Next (N);

      while Present (Next_Op)
        and then Nkind (Next_Op) /= N_Subprogram_Body
        and then Nkind (Next_Op) /= N_Entry_Body
      loop
         Next (Next_Op);
      end loop;

      return Next_Op;
   end Next_Protected_Operation;

   ----------------------
   -- Set_Discriminals --
   ----------------------

   procedure Set_Discriminals (Dec : Node_Id) is
      D       : Entity_Id;
      Pdef    : Entity_Id;
      D_Minal : Entity_Id;

   begin
      pragma Assert (Nkind (Dec) = N_Protected_Type_Declaration);
      Pdef := Defining_Identifier (Dec);

      if Has_Discriminants (Pdef) then
         D := First_Discriminant (Pdef);

         while Present (D) loop
            D_Minal :=
              Make_Defining_Identifier (Sloc (D),
                Chars => New_External_Name (Chars (D), 'D'));

            Set_Ekind (D_Minal, E_Constant);
            Set_Etype (D_Minal, Etype (D));
            Set_Discriminal (D, D_Minal);
            Set_Discriminal_Link (D_Minal, D);

            Next_Discriminant (D);
         end loop;
      end if;
   end Set_Discriminals;

   -----------------
   -- Set_Privals --
   -----------------

   procedure Set_Privals
      (Dec : Node_Id;
       Op  : Node_Id;
       Loc : Source_Ptr)
   is
      P_Decl    : Node_Id;
      P_Id      : Entity_Id;
      Priv      : Entity_Id;
      Def       : Node_Id;
      Body_Ent  : Entity_Id;
      Prec_Decl : constant Node_Id :=
                    Parent (Corresponding_Record_Type
                             (Defining_Identifier (Dec)));
      Prec_Def  : constant Entity_Id := Type_Definition (Prec_Decl);
      Obj_Decl  : Node_Id;
      P_Subtype : Entity_Id;
      New_Decl  : Entity_Id;
      Assoc_L   : Elist_Id := New_Elmt_List;
      Op_Id     : Entity_Id;

   begin
      pragma Assert (Nkind (Dec) = N_Protected_Type_Declaration);
      pragma Assert
        (Nkind (Op) = N_Subprogram_Body or else Nkind (Op) = N_Entry_Body);

      Def := Protected_Definition (Dec);

      if Present (Private_Declarations (Def)) then

         P_Decl := First (Private_Declarations (Def));

         while Present (P_Decl) loop
            if Nkind (P_Decl) = N_Component_Declaration then
               P_Id := Defining_Identifier (P_Decl);
               Priv :=
                 Make_Defining_Identifier (Loc,
                   New_External_Name (Chars (P_Id), 'P'));

               Set_Ekind     (Priv, E_Variable);
               Set_Etype     (Priv, Etype (P_Id));
               Set_Scope     (Priv, Scope (P_Id));
               Set_Esize     (Priv, Esize (Etype (P_Id)));
               Set_Alignment (Priv, Alignment (Etype (P_Id)));

               --  If the type of the component is an itype, we must
               --  create a new itype for the corresponding prival in
               --  each protected operation, to avoid scoping problems.
               --  We create new itypes by copying the tree for the
               --  component definition.

               if Is_Itype (Etype (P_Id)) then
                  Append_Elmt (P_Id, Assoc_L);
                  Append_Elmt (Priv, Assoc_L);

                  if Nkind (Op) = N_Entry_Body then
                     Op_Id := Defining_Identifier (Op);
                  else
                     Op_Id := Defining_Unit_Name (Specification (Op));
                  end if;

                  New_Decl := New_Copy_Tree (P_Decl, Assoc_L,
                                             New_Scope => Op_Id);
               end if;

               Set_Protected_Operation (P_Id, Op);
               Set_Prival (P_Id, Priv);
            end if;

            Next (P_Decl);
         end loop;
      end if;

      --  There is one more implicit private declaration: the object
      --  itself. A "prival" for this is attached to the protected
      --  body defining identifier.

      Body_Ent := Corresponding_Body (Dec);

      Priv :=
        Make_Defining_Identifier (Sloc (Body_Ent),
          Chars => New_External_Name (Chars (Body_Ent), 'R'));

      --  Set the Etype to the implicit subtype of Protection created when
      --  the protected type declaration was expanded. This node will not
      --  be analyzed until it is used as the defining identifier for the
      --  renaming declaration in the protected operation body, and it will
      --  be needed in the references expanded before that body is expanded.
      --  Since the Protection field is aliased, set Is_Aliased as well.

      Obj_Decl := First (Component_Items (Component_List (Prec_Def)));
      while Chars (Defining_Identifier (Obj_Decl)) /= Name_uObject loop
         Next (Obj_Decl);
      end loop;

      P_Subtype  := Etype (Defining_Identifier (Obj_Decl));
      Set_Etype (Priv, P_Subtype);
      Set_Is_Aliased (Priv);
      Set_Object_Ref (Body_Ent, Priv);

   end Set_Privals;

   ----------------------------
   -- Update_Prival_Subtypes --
   ----------------------------

   procedure Update_Prival_Subtypes (N : Node_Id) is

      function Process (N : Node_Id) return Traverse_Result;
      --  Update the etype of occurrences of privals whose etype does not
      --  match the current Etype of the prival entity itself.

      procedure Update_Array_Bounds (E : Entity_Id);
      --  Itypes generated for array expressions may depend on the
      --  determinants of the protected object, and need to be processed
      --  separately because they are not attached to the tree.

      -------------
      -- Process --
      -------------

      function Process (N : Node_Id) return Traverse_Result is
      begin
         if Is_Entity_Name (N)  then
            declare
               E : Entity_Id := Entity (N);

            begin
               if Present (E)
                 and then (Ekind (E) = E_Constant
                            or else Ekind (E) = E_Variable)
                 and then Nkind (Parent (E)) = N_Object_Renaming_Declaration
                 and then not Is_Scalar_Type (Etype (E))
                 and then Etype (N) /= Etype (E)
               then
                  Set_Etype (N, Etype (Entity (Original_Node (N))));

                  --  If the prefix has an actual subtype that is different
                  --  from the nominal one, update the types of the indices,
                  --  so that the proper constraints are applied. Do not
                  --  apply this transformation to a packed array, where the
                  --  index type is computed for a byte array and is different
                  --  from the source index.

                  if Nkind (Parent (N)) = N_Indexed_Component
                    and then
                      not Is_Bit_Packed_Array (Etype (Prefix (Parent (N))))
                  then
                     declare
                        Indx1 : Node_Id;
                        I_Typ : Node_Id;

                     begin
                        Indx1 := First (Expressions (Parent (N)));
                        I_Typ := First_Index (Etype (N));

                        while Present (Indx1) and then Present (I_Typ) loop

                           if not Is_Entity_Name (Indx1) then
                              Set_Etype (Indx1, Base_Type (Etype (I_Typ)));
                           end if;

                           Next (Indx1);
                           Next_Index (I_Typ);
                        end loop;
                     end;
                  end if;

               elsif Present (E)
                 and then Ekind (E) = E_Constant
                 and then Present (Discriminal_Link (E))
               then
                  Set_Etype (N, Etype (E));
               end if;
            end;

            return OK;

         elsif Nkind (N) = N_Defining_Identifier
           or else Nkind (N) = N_Defining_Operator_Symbol
           or else Nkind (N) = N_Defining_Character_Literal
         then
            return Skip;

         elsif Nkind (N) = N_String_Literal then
            --  array type, but bounds are constant.
            return OK;

         elsif Nkind (N) = N_Object_Declaration
           and then Is_Itype (Etype (Defining_Identifier (N)))
           and then Is_Array_Type (Etype (Defining_Identifier (N)))
         then
            Update_Array_Bounds (Etype (Defining_Identifier (N)));
            return OK;

         --  For array components of discriminated records, use the
         --  base type directly, because it may depend indirectly
         --  on the discriminants of the protected type. Cleaner would
         --  be a systematic mechanism to compute actual subtypes of
         --  private components ???

         elsif Nkind (N) in N_Has_Etype
           and then Present (Etype (N))
           and then Is_Array_Type (Etype (N))
           and then Nkind (N) = N_Selected_Component
           and then Has_Discriminants (Etype (Prefix (N)))
         then
            Set_Etype (N, Base_Type (Etype (N)));
            return OK;

         else
            if Nkind (N) in N_Has_Etype
              and then Present (Etype (N))
              and then Is_Itype (Etype (N)) then

               if Is_Array_Type (Etype (N)) then
                  Update_Array_Bounds (Etype (N));

               elsif Is_Scalar_Type (Etype (N)) then
                  Update_Prival_Subtypes (Type_Low_Bound  (Etype (N)));
                  Update_Prival_Subtypes (Type_High_Bound (Etype (N)));
               end if;
            end if;

            return OK;
         end if;
      end Process;

      -------------------------
      -- Update_Array_Bounds --
      -------------------------

      procedure Update_Array_Bounds (E : Entity_Id) is
         Ind : Node_Id;

      begin
         Ind := First_Index (E);

         while Present (Ind) loop
            Update_Prival_Subtypes (Type_Low_Bound  (Etype (Ind)));
            Update_Prival_Subtypes (Type_High_Bound (Etype (Ind)));
            Next_Index (Ind);
         end loop;
      end Update_Array_Bounds;

      procedure Traverse is new Traverse_Proc;

   --  Start of processing for Update_Prival_Subtypes

   begin
      Traverse (N);
   end Update_Prival_Subtypes;

end Exp_Ch9;