New submission from Stan <hexorgs...@gmail.com>:
Checking if thread.is_alive() while thread is checking on Process.is_alive() seemingly causes undefined behavior. The attached POC is expected to print "ThreadN.data == 1999" for N in range(0, 20) with some repeats. However the integers are spread all over the place. Moreover sometimes one or more of the threads never terminate resulting in technically infinite amount of "ThreadN.data == ###" prints. In python2.7.15 I never observed a thread lock (only early terminations), but in python3.4.8 I did. You may have to adjust max_count variable to have higher success rate of thread locking. I got about 40% chance of `python3 bug_test.py` never finishing on an Intel(R) Core(TM) i7-4610M CPU @ 3.00GHz ---------- files: bug_test.py messages: 331106 nosy: Hexorg priority: normal severity: normal status: open title: Thread.is_alive while running Process.is_alive causes either premature termination or never-terminating. type: behavior versions: Python 2.7, Python 3.4 Added file: https://bugs.python.org/file47975/bug_test.py _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue35419> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
