[gcc r13-4200] ada: Adjust recent change for returns involving function calls

[Marc Poulhi?s <dkm@gcc.gnu.org>]

https://gcc.gnu.org/g:2473f28d79c480192aba783a08de8b0285c08213

commit r13-4200-g2473f28d79c480192aba783a08de8b0285c08213
Author: Eric Botcazou <ebotcazou@adacore.com>
Date:   Wed Nov 16 03:58:17 2022 +0100

    ada: Adjust recent change for returns involving function calls
    
    gcc/ada/
    
            * gcc-interface/decl.cc (gnat_to_gnu_entity) <E_Constant>: Revert
            latest change.
            * gcc-interface/trans.cc (gnat_to_gnu) <N_Object_Declaration>:
            Tweak latest change.

Diff:
---
 gcc/ada/gcc-interface/decl.cc  | 11 -----------
 gcc/ada/gcc-interface/trans.cc | 11 ++++++++---
 2 files changed, 8 insertions(+), 14 deletions(-)

diff --git a/gcc/ada/gcc-interface/decl.cc b/gcc/ada/gcc-interface/decl.cc
index e25ce498f2c..c383f9b218a 100644
--- a/gcc/ada/gcc-interface/decl.cc
+++ b/gcc/ada/gcc-interface/decl.cc
@@ -637,17 +637,6 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition)
       break;
 
     case E_Constant:
-      /* If this is a constant related to a return in a function returning by
-	 invisible reference without expression, get the return object.  */
-      if (Is_Related_To_Func_Return (gnat_entity)
-	  && current_function_decl
-	  && TREE_ADDRESSABLE (TREE_TYPE (current_function_decl))
-	  && !gnu_expr)
-	{
-	  gnu_decl = DECL_RESULT (current_function_decl);
-	  break;
-	}
-
       /* Ignore constant definitions already marked with the error node.  See
 	 the N_Object_Declaration case of gnat_to_gnu for the rationale.  */
       if (definition
diff --git a/gcc/ada/gcc-interface/trans.cc b/gcc/ada/gcc-interface/trans.cc
index d0ff741585e..1cd621a9377 100644
--- a/gcc/ada/gcc-interface/trans.cc
+++ b/gcc/ada/gcc-interface/trans.cc
@@ -6482,9 +6482,10 @@ gnat_to_gnu (Node_Id gnat_node)
 
 	 then elide the temporary by forwarding the return object to Func:
 
+	   result_type *Rnn = (result_type *) <retval>;
 	   *<retval> = Func (); [return slot optimization]
 	   [...]
-	   return <retval>;
+	   return Rnn;
 
 	 That's necessary if the result type needs finalization because the
 	 temporary would never be adjusted as Expand_Simple_Function_Return
@@ -6496,8 +6497,12 @@ gnat_to_gnu (Node_Id gnat_node)
 	  && current_function_decl
 	  && TREE_ADDRESSABLE (TREE_TYPE (current_function_decl)))
 	{
-	  gnu_result = gnat_to_gnu_entity (gnat_temp, NULL_TREE, true);
-	  gnu_result = build_unary_op (INDIRECT_REF, NULL_TREE, gnu_result);
+	  gnat_to_gnu_entity (gnat_temp,
+			      DECL_RESULT (current_function_decl),
+			      true);
+	  gnu_result
+	    = build_unary_op (INDIRECT_REF, NULL_TREE,
+			      DECL_RESULT (current_function_decl));
 	  gnu_result
 	    = Call_to_gnu (Prefix (Expression (gnat_node)),
 			   &gnu_result_type, gnu_result,