--- old/src/share/vm/gc/shared/genCollectedHeap.hpp	2016-09-12 15:41:12.642114758 +0200
+++ new/src/share/vm/gc/shared/genCollectedHeap.hpp	2016-09-12 15:41:12.534114754 +0200
@@ -184,7 +184,7 @@
   // We may support a shared contiguous allocation area, if the youngest
   // generation does.
   bool supports_inline_contig_alloc() const;
-  HeapWord** top_addr() const;
+  HeapWord* volatile* top_addr() const;
   HeapWord** end_addr() const;
 
   // Perform a full collection of the heap; intended for use in implementing