Lib/threading.py gets into infinite recursion while testing (or using)
it with verbose set. This didn't happen before because Thread.__started
didn't use to be an Event, but now it is.

Typical situation:
_DummyThread calls _Thread__started.set, which calls
__started.__cond.notify_all(), which calls __cond.notify(). If there are
no waiters, it calls _Verbose._note, which calls currentThread, but if
there is no current thread _DummyThread is called, which calls
_Thread__started.set ...