Calling python from C with OpenMP

[Sturla Molden]

<oysteijo at gmail.com> wrote:

> Second and most important question: When I run this code it sometimes
> segementation faults, and sometimes some threads run normal and some
> other threads says "Cannot call 'do_multiply'". Sometimes I get the
> message: Fatal Python error: GC object already tracked. And some times it
> even runs normally...
> I understand there is some kind of race condition here, where python
> tries to refer to some memory that has been already released. But how can
> I avoid this? What am I doing wrong? (or, less likely, is this a bug?)


You must own the GIL before you can safely use the Python C API, object
creation and refcounting in particular. Use the "Simplified GIL API" to
grab the GIL and release it when you are done.