--- old/src/share/vm/gc_implementation/g1/concurrentMarkThread.hpp	2010-11-16 18:11:10.000000000 +0100
+++ new/src/share/vm/gc_implementation/g1/concurrentMarkThread.hpp	2010-11-16 18:11:10.000000000 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -22,6 +22,11 @@
  *
  */
 
+#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARKTHREAD_HPP
+#define SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARKTHREAD_HPP
+
+#include "gc_implementation/shared/concurrentGCThread.hpp"
+
 // The Concurrent Mark GC Thread (could be several in the future).
 // This is copied from the Concurrent Mark Sweep GC Thread
 // Still under construction.
@@ -93,3 +98,5 @@
   // shutdown
   void stop();
 };
+
+#endif // SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARKTHREAD_HPP