diff -r 74cd10898bea -r 842b840e67db src/share/vm/gc_implementation/g1/g1OopClosures.hpp
--- a/src/share/vm/gc_implementation/g1/g1OopClosures.hpp	Mon Jun 13 13:48:18 2011 +0200
+++ b/src/share/vm/gc_implementation/g1/g1OopClosures.hpp	Tue Jun 14 10:33:43 2011 -0400
@@ -33,6 +33,7 @@
 class CMBitMap;
 class CMMarkStack;
 class G1ParScanThreadState;
+class CMTask;
 
 // A class that scans oops in a given heap region (much as OopsInGenClosure
 // scans oops in a generation.)
@@ -176,4 +177,16 @@
   int out_of_region() { return _out_of_region; }
 };
 
+// Closure for iterating over object fields during concurrent marking
+class G1CMOopClosure : public OopClosure {
+  G1CollectedHeap*   _g1h;
+  ConcurrentMark*    _cm;
+  CMTask*            _task;
+public:
+  G1CMOopClosure(G1CollectedHeap* g1h, ConcurrentMark* cm, CMTask* task);
+  template <class T> void do_oop_nv(T* p);
+  virtual void do_oop(      oop* p) { do_oop_nv(p); }
+  virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
+};
+
 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_HPP