--- a/src/hotspot/share/gc/parallel/psParallelCompact.hpp	Thu Apr 26 12:54:53 2018 +0200
+++ b/src/hotspot/share/gc/parallel/psParallelCompact.hpp	Thu May 03 14:09:00 2018 +0200
@@ -968,6 +968,7 @@
   static SpaceInfo            _space_info[last_space_id];
 
   // Reference processing (used in ...follow_contents)
+  static SpanSubjectToDiscoveryClosure  _span_based_discoverer;
   static ReferenceProcessor*  _ref_processor;
 
   // Values computed at initialization and used by dead_wood_limiter().