--- a/hotspot/src/share/vm/gc_implementation/g1/heapRegionSets.hpp	Wed Nov 02 08:04:23 2011 +0100
+++ b/hotspot/src/share/vm/gc_implementation/g1/heapRegionSets.hpp	Mon Nov 07 22:11:12 2011 -0500
@@ -61,6 +61,30 @@
   SecondaryFreeRegionList(const char* name) : FreeRegionList(name) { }
 };
 
+//////////////////// OldRegionSet ////////////////////
+
+class OldRegionSet : public HeapRegionSet {
+protected:
+  virtual const char* verify_region_extra(HeapRegion* hr);
+
+  virtual bool regions_humongous() { return false; }
+  virtual bool regions_empty()     { return false; }
+
+public:
+  OldRegionSet(const char* name) : HeapRegionSet(name) { }
+};
+
+//////////////////// MasterOldRegionSet ////////////////////
+
+class MasterOldRegionSet : public OldRegionSet {
+private:
+protected:
+  virtual bool check_mt_safety();
+
+public:
+  MasterOldRegionSet(const char* name) : OldRegionSet(name) { }
+};
+
 //////////////////// HumongousRegionSet ////////////////////
 
 class HumongousRegionSet : public HeapRegionSet {