Build dist-x86_64-unknown-linux-musl releases

[andylizi]

Closes #4956.

• Artifact sample: rust-analyzer-x86_64-unknown-linux-musl.gz
• Build time: ~14m

$ ls -lh
-rwxr-xr-x    1 root     root       29.7M Feb 13 18:24 rust-analyzer-x86_64-unknown-linux-musl

$ ldd rust-analyzer-x86_64-unknown-linux-musl
        /lib/ld-musl-x86_64.so.1 (0x7f2751f13000)
        libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x7f2750a78000)
        libc.musl-x86_64.so.1 => /lib/ld-musl-x86_64.so.1 (0x7f2751f13000)

$ ./rust-analyzer-x86_64-unknown-linux-musl --version
rust-analyzer 63fcf65

I can do aarch64-unknown-linux-musl if it's also needed.

[lnicola]

Oh, I didn't realize it was so easy to mix a container and an action 😕.

[lnicola]

LGTM, thank you!

bors r+

Do you also want to add support to the Code extension? It's around here, but I'm not sure how to detect that the current distro is based on Musl (except checking /etc/os-release).

https://stackoverflow.com/a/60471114 runs ldd on a random binary, FWIW.

[bors]

Build succeeded:

• Rust (macos-latest)
• Rust (ubuntu-latest)
• Rust (windows-latest)
• TypeScript (ubuntu-latest)
• TypeScript (windows-latest)

[lnicola]

My understanding is that running Code on Alpine isn't a common thing, so I guess we can punt on the extension support.

[andylizi]

Hardly anyone would want to run VS Code itself on Alpine I suppose, but it's much more common when using Dev Container which explicitly supports x86_64 Alpine. When writing Rust applications for Docker container, OpenWRT or other musl-based environments, it's much better to develop and debug in a dev container. That way one doesn't have to go through the trouble of setting up cross compilation, nor will they find their code somehow doesn't work on musl only after having finished it on their glibc machine.

But it's also true after all that the user base for musl is much smaller than glibc. Since properly detecting musl is apparently not easy, how about we add a note or something to the user manual? That way those who have need of it can easily find the information to set it up themselves, instead of being confused by an unhelpful error message like "Cannot activate rust-analyzer: bootstrap error." (which, on that note, can be improved too)