Add linux_aarch64 platform

[christianbundy]

Problem

We aren't building wheels for linux_aarch64, which is a commonly used architecture. For example, when using Docker on an Apple M1 Pro:

$ docker run ubuntu uname -sm
Linux aarch64

Solution

Add aarch64 to CIBW_ARCHS_LINUX, add QEMU for emulation, and add an override to cibuildwheel.toml that runs only testcheck. This takes about 90 minutes for manylinux and 2 hours for musllinux.

---

See-also: #37

[achimnol]

@christianbundy @hauntsaninja Now we have native arm64 GitHub Actions runners for Ubuntu and Windows.
https://github.blog/2024-06-03-arm64-on-github-actions-powering-faster-more-efficient-build-systems/
This requires the large github runners setup in the repository or organization. Once done, this PR could avoid using the qemu action but use the native arm64 runner.

[komapa]

Hello, is this closer to being merged? Thank you!

[cdce8p]

Looking at the PyPI download stats, I also think it would make sense to add wheels for aarch64.

It's a bit unfortunate that the build takes so much longer than any of the other platforms. Maybe we should only build manylinux_aarch64 for now? @hauntsaninja What do you think?

When Github finally makes ARM runners available for free plans as well, we could reconsider that. github/roadmap#970

pypinfo -pc --days 28 --all --limit 20 \
    --where 'details.cpu != "None"' 'mypy==1.13.*' system cpu libc

system_name	cpu	libc_name	percent	download_count	Wheels
Linux	x86_64	glibc	89.63%	12,154,910	x
Windows	AMD64	None	3.65%	494,638	x
Linux	aarch64	glibc	2.69%	364,335	<--
Darwin	arm64	None	2.03%	275,469	x
Linux	x86_64	None	1.07%	145,756	x
Darwin	x86_64	None	0.53%	71,899	x
Linux	x86_64	musl	0.30%	41,083	x
Linux	aarch64	None	0.05%	7,371
Linux	i686	glibc	0.02%	2,045
Linux	s390x	glibc	0.01%	748
Linux	aarch64	musl	0.00%	677
Linux	ppc64le	glibc	0.00%	601

[hauntsaninja]

Thanks for the data. It does look like the musllinux aarch64 wheels are over two hours, which is much slower than even the manylinux aarch64 wheels, and benefits 0.00% of users. Pushed a commit dropping them. After that, we can merge and see. Worst case we revert and wait for Github to ship ARM runners.

[christianbundy]

Good call, thanks! Looking forward to checking out the impact here.

[cdce8p]

Good call, thanks! Looking forward to checking out the impact here.

Mypy 1.14.1 just shipped with manylinux_aarch64 wheels.
https://pypi.org/project/mypy/1.14.1/#files

[achimnol]

Finally!!!! 🎉