Enable -march=native through a special option for selected ports

[Vincent Habchi]

On 30 juin 2013, at 08:38, Blair Zajac <blair at orcaware.com> wrote:

> My only comment is that +native is ambiguous, maybe name it +arch-native or +march-native?

Agreed. I chose the name as a mere example. Note that this will prove more tricky than a simple flag replacement. For instance, ‘-march=native’ cannot be used with gcc/gfortran, because this leads to the emission of AVX instructions that are unknown to the antiquated as(1) utility gccXX relies on. It will only work with clang/clang-mp-3.3 and above.

Vincent