--- old/src/share/vm/gc/g1/g1RemSet.cpp 2017-08-20 02:08:32.175396349 -0400 +++ new/src/share/vm/gc/g1/g1RemSet.cpp 2017-08-20 02:08:32.059390398 -0400 @@ -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; } }