The ClearResponsibleAtSTW enum value in src/hotspot/share/runtime/synchronizer.cpp is set to 0 and only used in a single place:
if (ClearResponsibleAtSTW) mid->_Responsible = NULL;
Since the value is 0/false that code is effectively dead. The enum and the dead code should be removed.
if (ClearResponsibleAtSTW) mid->_Responsible = NULL;
Since the value is 0/false that code is effectively dead. The enum and the dead code should be removed.