diff -r 7504e7937183 -r 31b0e90ddbf0 src/hotspot/share/gc/z/zMark.cpp
--- a/src/hotspot/share/gc/z/zMark.cpp	Thu Aug 09 11:24:30 2018 +0200
+++ b/src/hotspot/share/gc/z/zMark.cpp	Thu Aug 09 11:24:30 2018 +0200
@@ -70,6 +70,10 @@
     _ncontinue(0),
     _nworkers(0) {}
 
+bool ZMark::is_initialized() const {
+  return _allocator.is_initialized();
+}
+
 size_t ZMark::calculate_nstripes(uint nworkers) const {
   // Calculate the number of stripes from the number of workers we use,
   // where the number of stripes must be a power of two and we want to