sci-libs/gsl-2.4 version bump for issue #813

[kiwifb]

I also fixed https in all ebuild to keep repoman happy. However I didn't migrate 1.16 to EAPI 6 or from autotools-multilib.

Controversial bit: the use of fma instructions leads to failures in the testsuite. So I explicitly disable them if they are available. I cannot just filter them since -march=native will enable them when available.

[heroxbd]

Could you please forward thism fma issue upstream?

[kiwifb]

I intend too, although I believe it to be fundamentally the same issue than something already opened since gsl-2.1 (IRC), it was reported for avx, which happens to enable fma where available as well. They probably can do something about the tolerance of that test. The tolerance code is incredibly nebulous to the newcomer otherwise I would have gone that way already.

[heroxbd]

Which gsl bug are you referring to? Let's point to the bug as a reference in the ebuild.

Probably this one https://savannah.gnu.org/bugs/?49697

Does that mean we should pass -mno-avx as well?

[kiwifb]

I am fairly sure it is a related issue to https://savannah.gnu.org/bugs/?49697 but I only have one discrepancy I believe. It is otherwise very similar I believe.

[kiwifb]

For -mno-avx I don't believe so. -mno-fma is more precise than -mno-avx. As in, you need avx to enable fma in the first place I think.