re PR debug/39485 (-O0 -g still puts whole object to a register)

	PR debug/39485
	* function.c (use_register_for_decl): When not optimizing, disregard
	register keyword for variables with types containing methods.

From-SVN: r144939

gcc/ChangeLog

@@ -12,6 +12,10 @@
 	* function.c (struct temp_slot): Likewise.
 	* cfgloop.h (struct loop): Likewise.
 
+	PR debug/39485
+	* function.c (use_register_for_decl): When not optimizing, disregard
+	register keyword for variables with types containing methods.
+
 2009-03-18  Sebastian Pop  <sebastian.pop@amd.com>
 
 	PR middle-end/39447

gcc/function.c

@@ -1942,7 +1942,28 @@ use_register_for_decl (const_tree decl)
   if (DECL_IGNORED_P (decl))
     return true;
 
-  return (optimize || DECL_REGISTER (decl));
+  if (optimize)
+    return true;
+
+  if (!DECL_REGISTER (decl))
+    return false;
+
+  switch (TREE_CODE (TREE_TYPE (decl)))
+    {
+    case RECORD_TYPE:
+    case UNION_TYPE:
+    case QUAL_UNION_TYPE:
+      /* When not optimizing, disregard register keyword for variables with
+	 types containing methods, otherwise the methods won't be callable
+	 from the debugger.  */
+      if (TYPE_METHODS (TREE_TYPE (decl)))
+	return false;
+      break;
+    default:
+      break;
+    }
+
+  return true;
 }
 
 /* Return true if TYPE should be passed by invisible reference.  */