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

[Brad Johnson]

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!