--- a/src/share/vm/gc_implementation/parallelScavenge/psCompactionManager.inline.hpp	Wed Jun 30 11:52:10 2010 -0400
+++ b/src/share/vm/gc_implementation/parallelScavenge/psCompactionManager.inline.hpp	Thu Jul 01 21:40:45 2010 -0700
@@ -26,7 +26,16 @@
 {
   ObjArrayTask task(obj, index);
   assert(task.is_valid(), "bad ObjArrayTask");
-  if (!_objarray_queue.push(task)) {
-    _objarray_overflow_stack->push(task);
-  }
+  _objarray_stack.push(task);
 }
+
+void ParCompactionManager::push_region(size_t index)
+{
+#ifdef ASSERT
+  const ParallelCompactData& sd = PSParallelCompact::summary_data();
+  ParallelCompactData::RegionData* const region_ptr = sd.region(index);
+  assert(region_ptr->claimed(), "must be claimed");
+  assert(region_ptr->_pushed++ == 0, "should only be pushed once");
+#endif
+  region_stack()->push(index);
+}