sem_ch6.adb (Analyze_Subprogram_Body_Helper): If the body is created for SPARK_To_C...

2016-04-21  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch6.adb (Analyze_Subprogram_Body_Helper): If the body is
	created for SPARK_To_C, the entity must remain invisible so it
	does not overload subsequent references to the original function.
	* exp_ch6.adb (Build_Procedure_Body_Form, Replace_Returns):
	Handle Extended_Return_Statements by replacing it with a block
	with assignments and a simple return statement.
	* exp_util.adb (Build_Procedure_Form): Make procedure entity
	invisible after analyzing declaration, to prevent improper
	overloading.

From-SVN: r235306

gcc/ada/ChangeLog

+2016-04-21  Ed Schonberg  <schonberg@adacore.com>
+
+	* sem_ch6.adb (Analyze_Subprogram_Body_Helper): If the body is
+	created for SPARK_To_C, the entity must remain invisible so it
+	does not overload subsequent references to the original function.
+	* exp_ch6.adb (Build_Procedure_Body_Form, Replace_Returns):
+	Handle Extended_Return_Statements by replacing it with a block
+	with assignments and a simple return statement.
+	* exp_util.adb (Build_Procedure_Form): Make procedure entity
+	invisible after analyzing declaration, to prevent improper
+	overloading.
+
 2016-04-21  Javier Miranda  <miranda@adacore.com>
 
 	* sem_ch6.adb (Build_Subprogram_Declaration): Propagate the

gcc/ada/exp_ch6.adb

@@ -692,6 +692,38 @@ package body Exp_Ch6 is
                   end loop;
                end;
 
+            elsif Nkind (Stmt) = N_Extended_Return_Statement then
+               declare
+                  Ret_Obj : constant Entity_Id :=
+                              Defining_Entity
+                                (First (Return_Object_Declarations (Stmt)));
+                  Assign  : constant Node_Id :=
+                              Make_Assignment_Statement (Sloc (Stmt),
+                                Name       =>
+                                  New_Occurrence_Of (Param_Id, Loc),
+                                Expression =>
+                                  New_Occurrence_Of (Ret_Obj, Sloc (Stmt)));
+                  Stmts   : constant List_Id :=
+                              Statements (Handled_Statement_Sequence (Stmt));
+
+               begin
+                  Set_Assignment_OK (Name (Assign));
+
+                  Rewrite (Stmt,
+                    Make_Block_Statement (Sloc (Stmt),
+                      Declarations               =>
+                        Return_Object_Declarations (Stmt),
+                      Handled_Statement_Sequence =>
+                        Make_Handled_Sequence_Of_Statements (Loc,
+                          Statements =>
+                            Statements (Handled_Statement_Sequence (Stmt)))));
+
+                  Replace_Returns (Param_Id, Stmts);
+
+                  Append_To (Stmts, Assign);
+                  Append_To (Stmts, Make_Simple_Return_Statement (Loc));
+               end;
+
             elsif Nkind (Stmt) = N_If_Statement then
                Replace_Returns (Param_Id, Then_Statements (Stmt));
                Replace_Returns (Param_Id, Else_Statements (Stmt));

gcc/ada/exp_util.adb

@@ -929,6 +929,7 @@ package body Exp_Util is
 
       Func_Formal  : Entity_Id;
       Proc_Formals : List_Id;
+      Proc_Decl    : Node_Id;
 
    begin
       --  No action needed if this transformation was already done
@@ -969,13 +970,20 @@ package body Exp_Util is
       --  function declaration. The processing in Build_Procedure_Body_Form
       --  relies on this order.
 
-      Insert_After_And_Analyze (Unit_Declaration_Node (Subp),
+      Proc_Decl :=
         Make_Subprogram_Declaration (Loc,
           Specification =>
             Make_Procedure_Specification (Loc,
               Defining_Unit_Name       =>
                 Make_Defining_Identifier (Loc, Chars (Subp)),
-              Parameter_Specifications => Proc_Formals)));
+              Parameter_Specifications => Proc_Formals));
+
+      Insert_After_And_Analyze (Unit_Declaration_Node (Subp), Proc_Decl);
+
+      --  Entity of procedure must remain invisible so that it does not
+      --  overload subsequent references to the original function.
+
+      Set_Is_Immediately_Visible (Defining_Entity (Proc_Decl), False);
 
       --  Mark the function as having a procedure form
 

gcc/ada/sem_ch6.adb

@@ -4138,9 +4138,14 @@ package body Sem_Ch6 is
       --  that carries the return value.
 
       if Present (Cloned_Body_For_C) then
-         Rewrite (N,
-           Build_Procedure_Body_Form (Spec_Id, Cloned_Body_For_C));
+         Rewrite (N, Build_Procedure_Body_Form (Spec_Id, Cloned_Body_For_C));
          Analyze (N);
+
+         --  The entity for the created procedure must remain invisible, so it
+         --  does not participate in resolution of subsequent references to the
+         --  function.
+
+         Set_Is_Immediately_Visible (Corresponding_Spec (N), False);
       end if;
 
       Ghost_Mode := Save_Ghost_Mode;