--- a/hotspot/src/share/vm/memory/genOopClosures.hpp	Mon May 02 18:53:37 2011 -0700
+++ b/hotspot/src/share/vm/memory/genOopClosures.hpp	Wed May 04 00:41:48 2011 -0700
@@ -175,7 +175,7 @@
  protected:
   template <class T> inline void do_oop_work(T* p) {
     oop obj = oopDesc::load_decode_heap_oop(p);
-    guarantee(obj->is_oop_or_null(), err_msg("invalid oop: " INTPTR_FORMAT, obj));
+    guarantee(obj->is_oop_or_null(), err_msg("invalid oop: " INTPTR_FORMAT, (oopDesc*) obj));
   }
  public:
   virtual void do_oop(oop* p);