Support GitHub-hosted ubuntu arm64 runners

[ntkme]

https://github.blog/changelog/2025-01-16-linux-arm64-hosted-runners-now-available-for-free-in-public-repositories-public-preview/

GitHub added public arm64 runners today. Currently it fails with the following error:

Error: The current runner (ubuntu-24.04-arm64) was detected as self-hosted because the platform does not match a GitHub-hosted runner image (or that image is deprecated and no longer supported).

There are two runners available:

– ubuntu-24.04-arm
– ubuntu-22.04-arm

We need to create build on these runners with https://github.com/ruby/ruby-builder, and then add support in this repo.

Failed run:

https://github.com/sass-contrib/sass-embedded-host-ruby/actions/runs/12814387717

[ntkme]

While CRuby is missing linux-arm builds, JRuby and TruffleRuby are failing for something different:

Error: Error: versionSpec parameter is required
    at Object.find (/home/runner/work/_actions/ruby/setup-ruby/v1/dist/index.js:9042:15)
    at Module.toolCacheFind (/home/runner/work/_actions/ruby/setup-ruby/v1/dist/index.js:[6](https://github.com/sass-contrib/sass-embedded-host-ruby/actions/runs/12814387717/job/35730693868#step:6:7)30:15)
    at Module.install (/home/runner/work/_actions/ruby/setup-ruby/v1/dist/index.js:64968:26)
    at setupRuby (/home/runner/work/_actions/ruby/setup-ruby/v1/dist/index.js:65[7](https://github.com/sass-contrib/sass-embedded-host-ruby/actions/runs/12814387717/job/35730693868#step:6:8)99:38)
    at run (/home/runner/work/_actions/ruby/setup-ruby/v1/dist/index.js:65745:11)
    at /home/runner/work/_actions/ruby/setup-ruby/v1/dist/index.js:65944:40
    at /home/runner/work/_actions/ruby/setup-ruby/v1/dist/index.js:65946:3
    at Object.<anonymous> (/home/runner/work/_actions/ruby/setup-ruby/v1/dist/index.js:65949:12)
    at Module._compile (node:internal/modules/cjs/loader:1469:14)
    at Module._extensions..js (node:internal/modules/cjs/loader:154[8](https://github.com/sass-contrib/sass-embedded-host-ruby/actions/runs/12814387717/job/35730693868#step:6:9):10)

Supposedly JRuby and TruffleRuby both have linux arm64 support as of today so they should not fail.

[ntkme]

With a closer look, JRuby and TruffleRuby's problem is more or less the same as CRuby. The error was caused by incorrectly detecting GitHub hosted runner as a self-hosted runner, thus not able to get version available:

setup-ruby/index.js

Lines 61 to 68 in 868b3f0

	let version
	if (common.isSelfHostedRunner()) {
	// The list of available Rubies in the hostedtoolcache is unrelated to getAvailableVersions()
	version = parsedVersion
	} else {
	const engineVersions = installer.getAvailableVersions(platform, engine)
	version = validateRubyEngineAndVersion(platform, engineVersions, engine, parsedVersion)
	}

[eregon]

I'm usually not a fan of "duplicated" (or almost) issues but this one is well-phrased and a good summary, thanks!
I'll just close this and #577 when it's all done then.

[eregon]

Current status/self notes:

• 2.3.5 - 3.4 are built. older versions segfault or fail to build: linux-aarch64 builds ruby-builder#21
• truffleruby 23.1.0-23.1.2 fail to start due to known pagesize issue on linux-aarch64: https://github.com/ruby/ruby-builder/actions/runs/12847539239/job/35823944810

[eregon]

Done in https://github.com/ruby/setup-ruby/releases/tag/v1.213.0