How to set default gfortran specs option?

[Ian Lance Taylor]

xunxun <xunxun1982@gmail.com> writes:

> But now I only want to change default gfortran specs option.
>
> I try to use
>
> *f951:
> -march=native
>
> or
>
> *f951_options:
> -march=native
>
> These are all invalid.

As far as I know there is no spec f951, and there is no way to use the
specs file to change the options passed to the Fortran compiler.  The
Fortran frontend doesn't use any named specs that you can change; the
specs are compiled into the driver program directly, from the source
file gcc/fortran/lang-specs.h.

Ian