Message 352707 - Python tracker

FYI, I'm getting a similar deadlock in a child Python process which is stuck on locking a mutex from the dl library. See attached stack. 

I'm not using concurrent.futures however, the parent Python process is a test driver that uses threading.Thread and subprocess.Popen to spawn new processes... I'm not using os.fork().

This occurred on ArchLinux with Python 3.7.4.