--- old/src/share/vm/gc/parallel/psScavenge.cpp	2015-05-21 16:16:21.104770294 +0200
+++ new/src/share/vm/gc/parallel/psScavenge.cpp	2015-05-21 16:16:20.936764664 +0200
@@ -845,9 +845,9 @@
   _ref_processor =
     new ReferenceProcessor(mr,                         // span
                            ParallelRefProcEnabled && (ParallelGCThreads > 1), // mt processing
-                           (int) ParallelGCThreads,    // mt processing degree
+                           (uint) ParallelGCThreads,   // mt processing degree
                            true,                       // mt discovery
-                           (int) ParallelGCThreads,    // mt discovery degree
+                           (uint) ParallelGCThreads,   // mt discovery degree
                            true,                       // atomic_discovery
                            NULL);                      // header provides liveness info