--- old/src/share/vm/gc/g1/g1OopClosures.inline.hpp	2016-03-18 13:05:57.775358597 +0100
+++ new/src/share/vm/gc/g1/g1OopClosures.inline.hpp	2016-03-18 13:05:57.679355731 +0100
@@ -131,7 +131,7 @@
   if (!oopDesc::is_null(heap_oop)) {
     oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
     HeapRegion* hr = _g1h->heap_region_containing((HeapWord*) obj);
-    _cm->grayRoot(obj, obj->size(), _worker_id, hr);
+    _cm->grayRoot(obj, hr);
   }
 }
 
@@ -237,7 +237,7 @@
   assert(!_g1->heap_region_containing(obj)->in_collection_set(), "should not mark objects in the CSet");
 
   // We know that the object is not moving so it's safe to read its size.
-  _cm->grayRoot(obj, (size_t) obj->size(), _worker_id);
+  _cm->grayRoot(obj);
 }
 
 void G1ParCopyHelper::mark_forwarded_object(oop from_obj, oop to_obj) {
@@ -252,7 +252,7 @@
   // worker so we cannot trust that its to-space image is
   // well-formed. So we have to read its size from its from-space
   // image which we know should not be changing.
-  _cm->grayRoot(to_obj, (size_t) from_obj->size(), _worker_id);
+  _cm->grayRoot(to_obj);
 }
 
 template <G1Barrier barrier, G1Mark do_mark_object, bool use_ext>