bpo-45274: Fix Thread._wait_for_tstate_lock() race condition (GH-28532) (GH-28580)

Fix a race condition in the Thread.join() method of the threading
module. If the function is interrupted by a signal and the signal
handler raises an exception, make sure that the thread remains in a
consistent state to prevent a deadlock.
(cherry picked from commit a22be4943c119fecf5433d999227ff78fc2e5741)

Co-authored-by: Victor Stinner <vstinner@python.org>
2 files changed