SIGSEGV crash in ObjectMonitor::enter with latest Shenandoah JDK8

[Alexander Yakushev]

Hello Roman,

Sorry, I didn't have a chance to continue the investigation. We've reverted
to Shenandoah 1.0 since then and researched what it takes to move this
particular service to JDK11 (which is a good idea anyway).

I've noticed on Twitter that you managed to trigger a similar problem with
Netty in the same method (ScheduleFutureTask.cancel). Did it lead anywhere?