I haven't looked at Shenandoah and my GC experience is a bit stale, but to determine if something is weakly referenced, you need to determine whether or not som

I haven't looked at Shenandoah and my GC experience is a bit stale, but to determine if something is weakly referenced, you need to determine whether or not something is universally weakly referenced. A strong reference anywhere means it isn't weakly referenced at all, and as I recall it's been thought (for now) that while this may not require stopping the world to sweep the full set of references, it's a safer and more correct option.