[Cython] remaining open issues for 0.17

[Robert Bradshaw]

On Fri, Aug 10, 2012 at 12:31 PM, Robert Bradshaw <robertwb at gmail.com> wrote:
> On Fri, Aug 10, 2012 at 12:10 PM, Stefan Behnel <stefan_ml at behnel.de> wrote:
>> Robert Bradshaw, 10.08.2012 20:54:
>>> OK, the problem boiled down to using 'b' or 'B' for the format string
>>> for char rather than 'c'. See, e.g.
>>> http://docs.python.org/library/array.html . I've pushed a fix at
>>> https://github.com/robertwb/cython/commit/b0539cbc32c200a09b1fbddf2d6943e92aec2f3e
>>> , but it'd be good to have another set of eyes with someone more
>>> familiar with this code to be sure I didn't miss anything. It also
>>> involved a lot of changes to the tests
>>> https://github.com/robertwb/cython/commit/6bcc8fd8419e6e4079344788023029736610d5aa
>>> so is not exactly backwards compatible, though perhaps more correct.
>>
>> That's unfortunate, but since it's a bug, it needs fixing.
>
> Actually, this fix breaks numpy_test, and I'm not sure how to fix it
> given that numpy has no notion of a "possibly signed char" (unless we
> disallow using char/char* with numpy altogether, which is much more
> extreme, or don't enforce that signs match for char, which is likely
> more invasive). Ugh.

I suppose the lack of numpy support for (no-signed) char does explain
why we were in the state we were in. I've pushed another commit that
lets unsigned char == char == signed char for the purposes of buffer
comparison (though not transitively, so unsigned char != signed char).

- Robert