feat: Add support for ubuntu-24.04-arm GHA runner

[mayeut]

Run all tests on GitHub Actions Ubuntu 24.04 aarch64 runner.

The emulation tests are kept for now.

We could also run armv7l tests on those same runners but it's not part of auto arch because:
1: not all aarch64 systems can run aarch32 binaries (we need EL0 aarch32 support - mac Mx SoC or Cavium ThunderX do not provide this for exemple).
2: part of the armv7l images are still experimental

If we want to run armv7l, we can probably amend the tests on GHA to request both aarch64 & armv7l architectures.

Fix #2131

[joerick]

---

Examples test run

Branch: example-config-test---gha-arm-2025-01-20T09-04-55

Service	Config	Status
github	examples/github-minimal.yml

Generated by bin/run_example_ci_config.py

---

---

Examples test run

Branch: example-config-test---gha-arm-2025-01-20T09-05-21

Service	Config	Status
github	examples/github-with-qemu.yml

Generated by bin/run_example_ci_config.py

---

[joerick]

Assuming the above goes green (✅), this looks good to me!

[joerick]

Suggested change

	# configure cibuildwheel to build native archs ('auto'), and some
	# emulated ones
	# configure cibuildwheel on Linux to build native archs ('auto'),
	# and to split the remaining architectures between the x86_64 and
	# ARM runners

I don't love this way of doing ternary expressions, but it's all we have in GHA workflows, so I think adding a comment is nice.

[mayeut]

I included your proposal and extended a bit on the auto armv7l peculiarity. That might be a bit too verbose but that's strange enough to deserve a also comment (it's "native" in some circumstances hence not in auto).

[joerick]

This change looks good to me. Question for another PR, but it makes me wonder if we could detect armv7l support and include that in auto on machines where that's possible.

[mayeut]

if we could detect armv7l support and include that in auto on machines where that's possible.

That might be possible:

• don't allow on platform other that Linux
• try to run a small statically linked Linux exe & check if it works.

[henryiii]

Not sure this is a feature. Current cibuildwheel works fine with native ARM, already using it in several projects. :)

[joerick]

Adding it to the example config upgrades it to a ✨ feature in my book :) - similar to if there was a CI platform that happened to work, as soon as we add it to the test matrix and document that it's supported by cibuildwheel, I think it would count as a feature.

But yeah, there were no code changes required - previous versions of cibuildwheel work on native ARM perfectly :)

[webknjaz]

Should the actual ¹ text be dropped below as well?

[joerick]

That footnote still applies to Gitlab, who don't yet offer ARM runners.