--- a/src/hotspot/share/runtime/basicLock.hpp	Fri Aug 16 09:18:41 2019 +0200
+++ b/src/hotspot/share/runtime/basicLock.hpp	Tue Aug 06 10:48:21 2019 +0200
@@ -26,16 +26,22 @@
 #define SHARE_RUNTIME_BASICLOCK_HPP
 
 #include "oops/markOop.hpp"
+#include "runtime/atomic.hpp"
 #include "runtime/handles.hpp"
 
 class BasicLock {
   friend class VMStructs;
   friend class JVMCIVMStructs;
  private:
-  volatile markOop _displaced_header;
+  volatile markWord _displaced_header;
  public:
-  markOop      displaced_header() const               { return _displaced_header; }
-  void         set_displaced_header(markOop header)   { _displaced_header = header; }
+  markWord displaced_header() const {
+    return Atomic::load(&_displaced_header);
+  }
+
+  void set_displaced_header(markWord header) {
+    Atomic::store(header, &_displaced_header);
+  }
 
   void print_on(outputStream* st) const;