--- old/src/hotspot/share/gc/shared/memAllocator.cpp	2019-03-11 14:25:53.978355324 +0100
+++ new/src/hotspot/share/gc/shared/memAllocator.cpp	2019-03-11 14:25:53.770355327 +0100
@@ -376,12 +376,7 @@
 
 oop MemAllocator::finish(HeapWord* mem) const {
   assert(mem != NULL, "NULL object pointer");
-  if (UseBiasedLocking) {
-    oopDesc::set_mark_raw(mem, _klass->prototype_header());
-  } else {
-    // May be bootstrapping
-    oopDesc::set_mark_raw(mem, markOopDesc::prototype());
-  }
+  oopDesc::set_mark_raw(mem, Klass::default_prototype_header(_klass));
   // Need a release store to ensure array/class length, mark word, and
   // object zeroing are visible before setting the klass non-NULL, for
   // concurrent collectors.