NMethod sweeping triggered by WhiteBox crashed:

# SIGSEGV (0xb) at pc=0xf43c007d, pid=866, tid=3939502960
#
# JRE version: Java(TM) SE Runtime Environment (9.0) (build 1.9.0-internal-fastdebug-20150313150524.iignatye.8026047-b00)
# Java VM: Java HotSpot(TM) Client VM (1.9.0-internal-fastdebug-20150313150524.iignatye.8026047-b00 mixed mode linux-x86 )
# Problematic frame:
# j java.lang.ThreadGroup.add(Ljava/lang/Thread;)V+4

Stack trace:
j java.lang.ThreadGroup.add(Ljava/lang/Thread;)V+4
v ~StubRoutines::call_stub
V [libjvm.so+0x5933f4] JavaCalls::call_helper(JavaValue*, methodHandle*, JavaCallArguments*, Thread*)+0x13e4;; JavaCalls::call_helper(JavaValue*, methodHandle*, JavaCallArguments*, Thread*)+0x13e4
V [libjvm.so+0x8aa624] os::os_exception_wrapper(void (*)(JavaValue*, methodHandle*, JavaCallArguments*, Thread*), JavaValue*, methodHandle*, JavaCallArguments*, Thread*)+0x24;; os::os_exception_wrapper(void (*)(JavaValue*, methodHandle*, JavaCallArguments*, Thread*), JavaValue*, methodHandle*, JavaCallArguments*, Thread*)+0x24
V [libjvm.so+0x590c4e] JavaCalls::call_special(JavaValue*, KlassHandle, Symbol*, Symbol*, JavaCallArguments*, Thread*)+0x32e;; JavaCalls::call_special(JavaValue*, KlassHandle, Symbol*, Symbol*, JavaCallArguments*, Thread*)+0x32e
V [libjvm.so+0x591115] JavaCalls::call_special(JavaValue*, Handle, KlassHandle, Symbol*, Symbol*, Handle, Thread*)+0xd5;; JavaCalls::call_special(JavaValue*, Handle, KlassHandle, Symbol*, Symbol*, Handle, Thread*)+0xd5
V [libjvm.so+0xa1eafa] JavaThread::allocate_threadObj(Handle, char const*, bool, Thread*)+0x41a;; JavaThread::allocate_threadObj(Handle, char const*, bool, Thread*)+0x41a
V [libjvm.so+0xac8259] WhiteBox::create_sweeper_thread(Thread*)+0x129;; WhiteBox::create_sweeper_thread(Thread*)+0x129
V [libjvm.so+0xad340e] WB_ForceNMethodSweep+0x10e;; WB_ForceNMethodSweep+0x10e
j sun.hotspot.WhiteBox.forceNMethodSweep0()Ljava/lang/Thread;+0
j sun.hotspot.WhiteBox.forceNMethodSweep()V+1
j AllocationCodeBlobTest$$Lambda$8.run()V+4
j com.oracle.java.testlibrary.InfiniteLoop.run()V+4


Maybe related to JDK-8072377?