[SciPy-Dev] Use vecLibFort instead of Accelerate?

[Matthew Brett]

Hi,

On Sat, Oct 11, 2014 at 12:17 PM, Sturla Molden <sturla.molden at gmail.com> wrote:
> Matthew Brett <matthew.brett at gmail.com> wrote:
>
>> Is that correct - that using vecLibFort will _not_ fix this issue of
>> segfaults for float32 with numpy.dot? :
>>
>> https://github.com/numpy/numpy/issues/4007
>>
>> That would make it much less attractive...
>
> It fixes sgemv but not cblas_sgemv.

OK - thanks - I am starting to understand.

To state clearly for my own benefit:

* sgemv is the Fortran API call;
* cblas_sgemv is the C API call, used by numpy.dot

vecLibFort would fix any calls from scipy Fortran code to buggy
Accelerate sgemv, but would not affect the numpy.dot calls.

Do we (scipy) call sgemv at any point?   If not, how likely is it we
will save a user from hitting the sgemv Accelerate bug by including
the vecLibFort fix?

> A similar dlload/dlsym hack could be used for NumPy to replace cblas_sgemv
> in the same way.

Sturla - I know you worked on this before; would you consider putting
in a numpy PR to add this fix?  I will try to review with my limited
competence.

Cheers,

Matthew