diff --git a/gcc/ada/ChangeLog b/gcc/ada/ChangeLog
index 89f5cad29866e2cb9ab42987b555195d45ca271d..09469ac839bd65cceb8544aa60c339129331a85f 100644
--- a/gcc/ada/ChangeLog
+++ b/gcc/ada/ChangeLog
@@ -1,3 +1,8 @@
+2010-04-07  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gcc-interface/decl.c (gnat_to_gnu_entity) <E_Procedure>: Set default
+	alignment on the RETURN type built for the Copy-In Copy-Out mechanism.
+
 2010-04-07  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gcc-interface/trans.c (call_to_gnu): In the return-by-target-ptr case
diff --git a/gcc/ada/gcc-interface/decl.c b/gcc/ada/gcc-interface/decl.c
index 0effe88cd9fa167b8851405b3f4ed901b8442269..0b620a0c0b4fd66306c66663573d543741c6721f 100644
--- a/gcc/ada/gcc-interface/decl.c
+++ b/gcc/ada/gcc-interface/decl.c
@@ -4062,6 +4062,9 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, int definition)
 		    gcc_assert (TREE_CODE (gnu_return_type) == VOID_TYPE);
 		    gnu_return_type = make_node (RECORD_TYPE);
 		    TYPE_NAME (gnu_return_type) = get_identifier ("RETURN");
+		    /* Set a default alignment to speed up accesses.  */
+		    TYPE_ALIGN (gnu_return_type)
+		      = get_mode_alignment (ptr_mode);
 		    has_copy_in_out = true;
 		  }