[python-win32] C++ thread cannot acquire GIL

[Brad Johnson]

Brad Johnson <Brad.Johnson <at> ballardtech.com> writes:

> 
> I am embedding a Python interpreter in a C++ app for Windows.
> 
> The main thread in my application calls PyEval_InitThreads();
> 
> At some point, the main thread creates a new thread to do some concurrent work
> using the Python interpreter.
> 
> The trouble is that in my worker thread I am never able to complete the call
> PyEval_AcquireLock(), since something else must be holding the GIL (Python gets
> stuck in the WaitForSingleObject call)
> 
> I cannot figure out what is holding the GIL, and believe me I've looked. Any
> debugging tips or glaring errors in my methodology?
> 
> Thanks!
> 

Just a follow-up, I've found a solution to this problem. Apparently, I was
running into a known bug with the Python C API reported here
http://bugs.python.org/issue1720250. The workaround is also posted here.

I hope this is helpful for posterity that may run into this in the future.