--- old/src/share/vm/gc_implementation/g1/g1RemSet.hpp	2010-11-16 18:11:29.000000000 +0100
+++ new/src/share/vm/gc_implementation/g1/g1RemSet.hpp	2010-11-16 18:11:28.000000000 +0100
@@ -22,6 +22,9 @@
  *
  */
 
+#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP
+#define SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP
+
 // A G1RemSet provides ways of iterating over pointers into a selected
 // collection set.
 
@@ -215,3 +218,5 @@
   virtual void do_oop(narrowOop* p) { do_oop_work(p); }
   virtual void do_oop(      oop* p) { do_oop_work(p); }
 };
+
+#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1REMSET_HPP