--- old/src/share/vm/gc/cms/concurrentMarkSweepGeneration.hpp	2016-09-20 11:59:16.082110760 +0200
+++ new/src/share/vm/gc/cms/concurrentMarkSweepGeneration.hpp	2016-09-20 11:59:15.978110756 +0200
@@ -540,7 +540,7 @@
 
   // Overflow list of grey objects, threaded through mark-word
   // Manipulated with CAS in the parallel/multi-threaded case.
-  oop _overflow_list;
+  oopDesc* volatile _overflow_list;
   // The following array-pair keeps track of mark words
   // displaced for accommodating overflow list above.
   // This code will likely be revisited under RFE#4922830.
--- old/src/share/vm/gc/cms/parNewGeneration.hpp	2016-09-20 11:59:16.742110790 +0200
+++ new/src/share/vm/gc/cms/parNewGeneration.hpp	2016-09-20 11:59:16.642110785 +0200
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2016, 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
@@ -323,7 +323,7 @@
   // A list of from-space images of to-be-scanned objects, threaded through
   // klass-pointers (klass information already copied to the forwarded
   // image.)  Manipulated with CAS.
-  oop _overflow_list;
+  oopDesc* volatile _overflow_list;
   NOT_PRODUCT(ssize_t _num_par_pushes;)
 
   // This closure is used by the reference processor to filter out
@@ -383,7 +383,7 @@
   NOT_PRODUCT(bool should_simulate_overflow();)
 
   // Accessor for overflow list
-  oop overflow_list() { return _overflow_list; }
+  oop overflow_list() { return oop(_overflow_list); }
 
   // Push the given (from-space) object on the global overflow list.
   void push_on_overflow_list(oop from_space_obj, ParScanThreadState* par_scan_state);