[Bug fortran/82143] add a -fdefault-real-16 flag

[dominiq at lps dot ens.fr]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82143

--- Comment #9 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
> And to repeat it: Yes, I think there is an issue here to be fixed.
> Essentially what I'm looking for is an equivalent to ifort's "-real-size 128"
> option. I don't think that exists at the moment.

I don't know what fort is doing, but what is wrong with -freal-4-real-16?