ci: Add Linux Arm runner

[yutannihilation]

edit: I found it's too difficult to test Windows ARM at the moment. So, this pull request was changed to just adding a ubuntu-24.04-arm runner.

GitHub now provides Windows Arm64 runner.

https://github.blog/changelog/2025-04-14-windows-arm64-hosted-runners-now-available-in-public-preview/

I know hellorust had been ready for Arm64 from a long ago, so, I expected this pull request was just for ensuring it. However, it seems the R installation reports R.version$platform as x86_64-w64-mingw32, which makes this logic fail. So, please do not merge this for now.

hellorust/tools/rustarch.R

Lines 3 to 4 in 0f2dc03

	arch <- if(grepl("aarch", R.version$platform)){
	"aarch64-pc-windows-gnullvm"

[eitsupi]

It seems that the R on the PATH is not arm64 version.
https://github.com/r-rust/hellorust/actions/runs/14471329390/job/40585772582?pr=24#step:9:23

  shell: C:\Program Files (x86)\R\R-4.4.2\bin\x64\Rscript.EXE {0}

[eitsupi]

Doesn't this support windows-11-arm? 🤔
https://github.com/r-lib/actions/blob/bd49c52ffe281809afa6f0fecbf37483c5dd0b93/setup-r/src/installer.ts#L474-L477

[yutannihilation]

Oh, I didn't notice setup-r is ready for Rtools for ARM. But, it didn't work.

https://github.com/yutannihilation/hellorust/actions/runs/14470417956/job/40582638349

[yutannihilation]

It seems it's way too early to try to support Windows ARM. Even if I tweaked setup-r action to work, I found

• setup-r-dependencies doesn't work: there is no package called 'pak'
• rcmdcheck doesn't work: Error in get(name, envir = cache) : object 'rtools_path' not found

I'm giving up for now!

[eitsupi]

FYI: https://www.r-bloggers.com/2025/04/running-r-on-windows-on-arm-on-github-actions/

[yutannihilation]

Setting up R and Rtools isn't that difficult. You can just tweak a few lines of r-lib/actions/setup-r instead of writing that PowerShell from scratch! However,

• setup-r-dependencies and check-r-package don't work.
• Also, I'm not sure if https://www.r-project.org/nosvn/ is a place where we can use for CI.

[jeroen]

Unrelated, but the r-svn CI does build on arm64: https://github.com/r-devel/r-svn