bug#55848: [cuirass] workers stalled

[Maxim Cournoyer <maxim.cournoyer@gmail.com>]

Hi Mathieu!

[...]

> A few issues remain for aarch64:
>
> * grunewald and kreuzberg are not on <https://ci.guix.gnu.org/workers>.
>   Perhaps they were taken down while the substitute ratio was low to
>   avoid each worker independently recompiling expensive toolchains?
> * rust@1.39.0 (and thus all of Rust) is missing from ci and bordeaux. I
>   had expected this would have been working. I'll take a look and raise
>   a separate issue.

That's a known issue with mrustc; it only succeeds with x86_64; the
other architectures have problems.  That's a bug the mrustc author would
like to fix, so perhaps in time in will improve (especially if
interested parties can lend a hand).

There was also an attempt to cross-compile a rust/cargo bootstrap seed
for other architectures (branch: wip-cross-built-rust) but due to
complications with building rust as a static archive (it relies on
dynamic linking for its macro expand crates), the effort stalled.

Thanks,

Maxim