Add aarch64 support

[myhro]

Discussed in #212.

Still trying to figure why tests are failing with multiple errors. It's not clear which file or directory wasn't found.

Was able to reproduce it locally with cross test --target aarch64-unknown-linux-gnu. Interestingly enough, switching to aarch64-unknown-linux-musl works.

Edit: fixed switching to the expected aarch64-unknown-linux-musl.

[ducaale]

This happens because we are invoking the xh binary with the value of CARGO_TARGET_*_RUNNER. But for some reason, this value happens to be /linux-runner aarch64 in aarch64-unknown-linux-gnu rather than the usual qemu-*. To work around this issue, you can update the find_runner() function in tests/cli.rs to be like this:

fn find_runner() -> Option<String> {
    for (key, value) in std::env::vars() {
        if key.starts_with("CARGO_TARGET_") && key.ends_with("_RUNNER") && value.contains("qemu") {
            return Some(value);
        }
    }
    None
}

However, I am still in favor of adding aarch64-unknown-linux-musl and not aarch64-unknown-linux-gnu which doesn't work in termux.

[myhro]

This happens because we are invoking the xh binary with the value of CARGO_TARGET_*_RUNNER. But for some reason, this value happens to be /linux-runner aarch64 in aarch64-unknown-linux-gnu rather than the usual qemu-*.

Thanks for the explanation. Looking at the rustembedded/cross images, I've noticed that their CARGO_TARGET_*_RUNNER environment variables are quite different. In Dockerfile.aarch64-unknown-linux-gnu it's "/linux-runner aarch64" and on Dockerfile.aarch64-unknown-linux-musl it's just qemu-aarch64. That explains why tests ran fine on the latter.

However, I am still in favor of adding aarch64-unknown-linux-musl and not aarch64-unknown-linux-gnu which doesn't work in termux.

Sorry, I misread your suggestion in this comment (and also in the other one before). I've been mentioning the -gnu variant for aarch64 so many times in the discussion that I didn't notice you were suggesting the -musl one. I'm all in for the musl statically-linked option, like we are already doing with the x86_64 release.

I've updated the PR to make use of the aarch64-unknown-linux-musl one. Thanks for the clarification.

[ducaale]

Looks good, thanks!

[nicolasdanelon]

what about apple silicon 😭

[ducaale]

@nicolasdanelon can you open an issue for it? Thanks

[nicolasdanelon]

@ducaale sure.

[nicolasdanelon]

@ducaale it's working now man! 😮