--- old/src/share/vm/gc/g1/g1RemSet.cpp	2017-08-22 15:36:30.217167628 +0200
+++ new/src/share/vm/gc/g1/g1RemSet.cpp	2017-08-22 15:36:30.053167634 +0200
@@ -243,7 +243,7 @@
 
     bool marked_as_dirty = Atomic::cmpxchg(Dirty, &_in_dirty_region_buffer[region], Clean) == Clean;
     if (marked_as_dirty) {
-      size_t allocated = Atomic::add(1, &_cur_dirty_region) - 1;
+      size_t allocated = Atomic::add(1u, &_cur_dirty_region) - 1;
       _dirty_region_buffer[allocated] = region;
     }
   }