Test runtime/Monitor/SyncOnValueBasedClassTest.java recently triggered a SIGSEGV.

# SIGSEGV (0xb) at pc=0x00007f3e69094755, pid=61220, tid=61293
# V [libjvm.so+0xc35755] LightweightSynchronizer::inflate_and_enter(oopDesc*, BasicLock*, ObjectSynchronizer::InflateCause, JavaThread*, JavaThread*)+0x85

Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0xc35755] LightweightSynchronizer::inflate_and_enter(oopDesc*, BasicLock*, ObjectSynchronizer::InflateCause, JavaThread*, JavaThread*)+0x85 (atomic_linux_x86.hpp:48)
V [libjvm.so+0xc381fc] LightweightSynchronizer::enter(Handle, BasicLock*, JavaThread*)+0x64c (lightweightSynchronizer.cpp:693)
V [libjvm.so+0xe93527] SharedRuntime::monitor_enter_helper(oopDesc*, BasicLock*, JavaThread*)+0xc7 (synchronizer.inline.hpp:49)
V [libjvm.so+0x5c995b] Runtime1::monitorenter(JavaThread*, oopDesc*, BasicObjectLock*)+0x2b (c1_Runtime1.cpp:768)
v ~RuntimeStub::C1 Runtime monitorenter_nofpu_blob 0x00007f3e57ee27e3
J 462 c1 SyncOnValueBasedClassTest$LogTest.run()V (40 bytes) @ 0x00007f3e57f92a00 [0x00007f3e57f92880+0x0000000000000180]
J 461 c1 java.lang.Thread.run()V java.base@25-internal (23 bytes) @ 0x00007f3e57f9261c [0x00007f3e57f92580+0x000000000000009c]
v ~StubRoutines::call_stub 0x00007f3e57dd7ca6
V [libjvm.so+0x9a98b0] JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, JavaThread*)+0x2b0 (javaCalls.cpp:415)
V [libjvm.so+0x9ab21f] JavaCalls::call_virtual(JavaValue*, Handle, Klass*, Symbol*, Symbol*, JavaThread*)+0x1df (javaCalls.cpp:323)
V [libjvm.so+0xa847dc] thread_entry(JavaThread*, JavaThread*)+0x8c (jvm.cpp:2748)
V [libjvm.so+0x9c0468] JavaThread::thread_main_inner() [clone .part.0]+0xb8 (javaThread.cpp:772)
V [libjvm.so+0xfbb20f] Thread::call_run()+0x9f (thread.cpp:231)
V [libjvm.so+0xdc3e66] thread_native_entry(Thread*)+0xd6 (os_linux.cpp:877)
Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
v ~RuntimeStub::C1 Runtime monitorenter_nofpu_blob 0x00007f3e57ee27e3
J 462 c1 SyncOnValueBasedClassTest$LogTest.run()V (40 bytes) @ 0x00007f3e57f92a00 [0x00007f3e57f92880+0x0000000000000180]
J 461 c1 java.lang.Thread.run()V java.base@25-internal (23 bytes) @ 0x00007f3e57f9261c [0x00007f3e57f92580+0x000000000000009c]
v ~StubRoutines::call_stub 0x00007f3e57dd7ca6

siginfo: si_signo: 11 (SIGSEGV), si_code: 2 (SEGV_ACCERR), si_addr: 0x00007f3e69e55834

Machine info is
Host: Intel(R) Xeon(R) Platinum 8260M CPU @ 2.40GHz, 8 cores, 23G, SUSE Linux Enterprise Server 15 SP3
Time: Thu Apr 10 19:41:16 2025 CEST elapsed time: 0.334267 seconds (0d 0h 0m 0s)

Maybe important - UseCompactObjectHeaders was set on this build to test compat object headers.