--- old/src/share/vm/gc/serial/genMarkSweep.cpp	2015-06-22 11:04:42.898674852 +0200
+++ new/src/share/vm/gc/serial/genMarkSweep.cpp	2015-06-22 11:04:42.718673960 +0200
@@ -67,7 +67,7 @@
   // hook up weak ref data so it can be used during Mark-Sweep
   assert(ref_processor() == NULL, "no stomping");
   assert(rp != NULL, "should be non-NULL");
-  _ref_processor = rp;
+  set_ref_processor(rp);
   rp->setup_policy(clear_all_softrefs);
 
   GCTraceTime t1(GCCauseString("Full GC", gch->gc_cause()), PrintGC && !PrintGCDetails, true, NULL, _gc_tracer->gc_id());
@@ -136,7 +136,7 @@
   }
 
   // refs processing: clean slate
-  _ref_processor = NULL;
+  set_ref_processor(NULL);
 
   // Update heap occupancy information which is used as
   // input to soft ref clearing policy at the next gc.