[Numpy-discussion] Simplifying compiler optimization flags logic (fortran compilers)

[Michael Abshoff]

Jarrod Millman wrote:
> On Sat, Nov 1, 2008 at 1:07 AM, Robert Kern <robert.kern at gmail.com> wrote:

Hi,

>> On Fri, Oct 31, 2008 at 05:25, David Cournapeau
>> <david at ar.media.kyoto-u.ac.jp> wrote:
>>>    I was wondering whether it was really worth having a lot of magic
>>> going on in fcompilers for flags like -msse2 and co (everything done in
>>> get_flags_arch, for example). It is quite fragile (we had several
>>> problems wrt buggy compilers, buggy CPU detection), and I am not sure it
>>> buys us much anyway. Did some people notice a difference between
>>> gfortran -O3 -msse2 and gfortran -O3 ?
>> You're probably right.

we removed setting the various SSE flags in Sage's numpy install because 
they caused segfaults when using gfortran. I don't think that there is a 
significant performance difference with SSE for that code because we use 
Lapack and ATLAS build with SSE when it is available.

> I think it is probably best to take out some of the magic in fcompilers as well.
> 


Cheers,

Michael