diff -r 6821d0a573c3 -r f1adc8069935 hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp
--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp	Wed Sep 11 10:14:32 2013 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.cpp	Wed Sep 11 10:19:16 2013 +0200
@@ -481,9 +481,8 @@
 
 ConcurrentMark::ConcurrentMark(G1CollectedHeap* g1h, ReservedSpace heap_rs) :
   _g1h(g1h),
-  _markBitMap1(MinObjAlignment - 1),
-  _markBitMap2(MinObjAlignment - 1),
-
+  _markBitMap1(log2_intptr(MinObjAlignment)),
+  _markBitMap2(log2_intptr(MinObjAlignment)),
   _parallel_marking_threads(0),
   _max_parallel_marking_threads(0),
   _sleep_factor(0.0),