[Python-Dev] Issue 20891 - PyGILState_Ensure on non-Python thread causes fatal error

[Steve Dower]

Hi python-dev

Just wanted to draw some attention to http://bugs.python.org/issue20891, which I just created. (I hope I got the right people on the nosy list, but going broad just to be safe.)

Details and the discussion can go on there, but the basic gist is that C threads can't safely call PyGILState_Ensure() any more unless PyEval_InitThreads() has been called from an existing Python thread - you get a fatal error because there is no current thread state. Since PyGILState_Ensure is supposed to create this thread state, I believe this is a serious regression and would really like to see it fixed before 3.4 is released.

Cheers,
Steve