[gcc r13-7901] ada: Elide the copy in extended returns for nonlimited by-reference types

[gcc r13-7901] ada: Elide the copy in extended returns for nonlimited by-reference types

[Eric Botcazou]

https://gcc.gnu.org/g:2d0caa03cb6f7a5480e6540c1dfd7b0f2e267960

commit r13-7901-g2d0caa03cb6f7a5480e6540c1dfd7b0f2e267960
Author: Eric Botcazou <ebotcazou@adacore.com>
Date:   Tue Jul 11 10:59:17 2023 +0200

    ada: Elide the copy in extended returns for nonlimited by-reference types
    
    gcc/ada/
    
            * gcc-interface/trans.cc (gnat_to_gnu): Restrict previous change to
            the case where the simple return statement has got no storage pool.

Diff:
---
 gcc/ada/gcc-interface/trans.cc | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/gcc/ada/gcc-interface/trans.cc b/gcc/ada/gcc-interface/trans.cc
index c43af162309..54e0e8a7fbd 100644
--- a/gcc/ada/gcc-interface/trans.cc
+++ b/gcc/ada/gcc-interface/trans.cc
@@ -8478,8 +8478,8 @@ gnat_to_gnu (Node_Id gnat_node)
 
        5. If this is a reference to an unconstrained array which is used either
 	  as the prefix of an attribute reference that requires an lvalue or in
-	  a return statement, then return the result unmodified because we want
-	  to return the original bounds.
+	  a return statement without storage pool, return the result unmodified
+	  because we want to return the original bounds.
 
        6. Finally, if the type of the result is already correct.  */
 
@@ -8545,7 +8545,8 @@ gnat_to_gnu (Node_Id gnat_node)
 	   && Present (Parent (gnat_node))
 	   && ((Nkind (Parent (gnat_node)) == N_Attribute_Reference
 	        && lvalue_required_for_attribute_p (Parent (gnat_node)))
-	       || Nkind (Parent (gnat_node)) == N_Simple_Return_Statement))
+	       || (Nkind (Parent (gnat_node)) == N_Simple_Return_Statement
+		   && No (Storage_Pool (gnat_node)))))
     ;
 
   else if (TREE_TYPE (gnu_result) != gnu_result_type)