Python crashes when plotting with matplotlib in module importing swig generated wrapper

Question

I have a python module that imports a module generated with swig. When I try to call the show() function of matplotlib later in that module, python crashes without any hint, what went wrong. When I comment the import statement with the swig generated module out, everything works fine. Does anybody have a clue to what could be the reason for this behaviour? I'm aware that this is a very unspecific formulation of the problem. But, I don't expect a solution to my problem, just a hint to where I could look at to find the problem. Thanks.

Answer 1

I'd start with running the script under gdb and looking at the stack trace. Recent versions of gdb have built in support for python debugging.

$ gdb python
(gdb) run /path/to/script.py
# wait for crash #
(gdb) bt
# stack trace here #

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