re PR objc/45878 (Can't compile even a trivial ObjC program with -fexceptions -O2)

2010-10-13  Richard Guenther  <rguenther@suse.de>

	PR objc/45878
	* gimple-fold.c (gimple_fold_obj_type_ref): Leave OBJ_TYPE_REFs
	alone if there are no virtual methods.

	* objc.dg/pr45878.m: New testcase.

From-SVN: r165435

gcc/ChangeLog

+2010-10-13  Richard Guenther  <rguenther@suse.de>
+
+	PR objc/45878
+	* gimple-fold.c (gimple_fold_obj_type_ref): Leave OBJ_TYPE_REFs
+	alone if there are no virtual methods.
+
 2010-10-13  Richard Henderson  <rth@redhat.com>
 
 	* expr.c (build_personality_function): Take parameter LANG instead

gcc/gimple-fold.c

@@ -1524,9 +1524,9 @@ gimple_fold_obj_type_ref (tree ref, tree known_type)
   if (binfo)
     {
       HOST_WIDE_INT token = tree_low_cst (OBJ_TYPE_REF_TOKEN (ref), 1);
-      /* If there is no virtual methods fold this to an indirect call.  */
+      /* If there is no virtual methods leave the OBJ_TYPE_REF alone.  */
       if (!BINFO_VIRTUALS (binfo))
-	return OBJ_TYPE_REF_EXPR (ref);
+	return NULL_TREE;
       return gimple_fold_obj_type_ref_known_binfo (token, binfo);
     }
   else

gcc/testsuite/ChangeLog

+2010-10-13  Richard Guenther  <rguenther@suse.de>
+
+	PR objc/45878
+	* objc.dg/pr45878.m: New testcase.
+
 2010-10-13  Kai Tietz  <kai.tietz@onevision.com>
 
 	* gcc.dg/format/dfp-scanf-1.c: Disable for *-*-mingw* targets.

gcc/testsuite/objc.dg/pr45878.m

+/* { dg-do compile } */
+/* { dg-options "-O2 -fexceptions" } */
+
+typedef struct objc_object { Class class_pointer; } *id;
+typedef unsigned char  BOOL;
+
+@interface Object
+{
+  Class isa;
+}
+- (BOOL)isEqual:anObject;
+@end
+
+@interface NXConstantString: Object
+{
+  char *c_string;
+  unsigned int len;
+}
+@end
+
+void function (void)
+{
+  if ([@"strings" isEqual: (id)0])
+    {
+      ;
+    }
+}
+