diff a/src/hotspot/share/gc/shared/oopStorageSetParState.hpp b/src/hotspot/share/gc/shared/oopStorageSetParState.hpp
--- a/src/hotspot/share/gc/shared/oopStorageSetParState.hpp
+++ b/src/hotspot/share/gc/shared/oopStorageSetParState.hpp
@@ -37,10 +37,26 @@
   ParStateArray _par_states;
 
 public:
   OopStorageSetStrongParState();
 
-  template <typename Closure>
-  void oops_do(Closure* cl);
+  template <typename ClosureType>
+  void oops_do(ClosureType* cl);
+};
+
+template <bool concurrent, bool is_const>
+class OopStorageSetWeakParState {
+  typedef OopStorage::ParState<concurrent, is_const> ParStateType;
+  typedef ValueObjArray<ParStateType, OopStorageSet::weak_count> ParStateArray;
+
+  ParStateArray _par_states;
+
+public:
+  OopStorageSetWeakParState();
+
+  template <typename ClosureType>
+  void oops_do(ClosureType* cl);
+
+  void notify();
 };
 
 #endif // SHARE_GC_SHARED_OOPSTORAGESETPARSTATE_HPP