[Cython] SIGSEGV in __Pyx_CyFunction_traverse

[J Robert Ray]

I was getting a crash during module init of a cython module if a garbage
collection happens between a call to __Pyx_CyFunction_InitDefaults and the
code to populate the defaults.

The attached patch fixes the crash. This bug affects at least Cython 0.18
and 0.17.1.

__Pyx_CyFunction_InitDefaults was not completely zeroing the newly
allocated 'defaults' buffer.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/cython-devel/attachments/20130205/14123f5e/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: cython.patch
Type: application/octet-stream
Size: 539 bytes
Desc: not available
URL: <http://mail.python.org/pipermail/cython-devel/attachments/20130205/14123f5e/attachment.obj>