Victor,

Thanks for the updated patch.

I think you need to do a PyErr_Clear after the 'return PyLong_FromSize_t' line.

To be safe, you should probably check the exception type first, and either 
do a PyErr_Clear and continue if it's an OverflowError, or just return 
NULL if it's some other exception.  It's true that _PyLong_NumBits can't 
raise anything other than OverflowError at the moment, but you never know 
when that might change. :)

I'm also getting a 'malformed table' warning when building the 
documentation.