Assertion violation of GC_stop_count&THREAD_RESTARTED in GC_restart_all running disclaimtest

[ivmai]

Source: master (76fd8ee)
Build: https://github.com/ivmai/bdwgc/actions/runs/7492494318/job/20396153848
How to build/test: zig build -Denable_gc_assertions -Denable_redirect_malloc -Denable_parallel_mark=false test
Zig version: 0.12.0-dev.2076+8fd15c6ca
Host: Linux/x86_64
Occurrence: rare
Violated assertion in GC_restart_all: GC_ASSERT((GC_stop_count & THREAD_RESTARTED) != 0);
Output (disclaimtest):

Assertion failure: .../bdwgc/extra/../pthread_stop_world.c:1239