Add patch to enable building on Apple Silicon

[richard-vd]

Fixes #23. See also richfelker/musl-cross-make#129.

[uwinx]

@richard-vd, any updates on this?

[richard-vd]

I don't have write access to this repository to merge this PR and update the bottle, but if you want it working now then I suggest to have a look at the README.md and the recent commit history in my fork: https://github.com/richard-vd/homebrew-musl-cross.

[FiloSottile]

Like @richfelker in richfelker/musl-cross-make#129 (comment), I suspect the patches are right, and I believe they build a Hello World fine, but I would feel more confident pulling something with a solid justification or a backport from the GCC tree. Has upstream not fixed this yet?

[richfelker]

I doubt it breaks anything at runtime, but if it's not correct it could break building the toolchain for different hosts. That's why I'd like to see an explanation.

[uwinx]

Can confirm that using formula from this PR works for me.

[richard-vd]

Updated commit to include patch for gcc-10.3.0.

[DirectorX]

Any updates? Can I help somehow?

[FiloSottile]

Have these patches made it into upstream? If not, why? I do believe that they work when tested, but I am trying to understand why we don't have an official upstream patch to backport.

[richard-vd]

Last month this was committed to gcc master: gcc-mirror/gcc@834c8749

I will update the PR to use this patch instead.

[FiloSottile]

Awesome, thank you!

[richfelker]

Thanks! Updating the PR to use the official fix will be much appreciated, and suffices to document that it's a reasonable solution.

[FiloSottile]

@richard-vd friendly ping, do you want to import the new patch or should I go ahead with it?

[richard-vd]

I redid the Apple silicon patches for gcc-6.5.0 .. gcc-10.3.0 using commits from gcc upstream.

The URL of this patch points to today's commit in richfelker/musl-cross-make#129. I hope both PRs can be merged now.

[ismail]

@FiloSottile Friendly ping… richfelker/musl-cross-make#129 looks like it will not be merged soon, could you merge this one?

[FiloSottile]

Ah, yes, thank you for syncing with upstream!

[ismail]

All the glory to @richard-vd , thanks for taking time to fix this!