Rust: `miri` no longer builds after rust-lang/rust#63015

[rust-highfive]

Hello, this is your friendly neighborhood mergebot.
After merging PR rust-lang/rust#63015, I observed that the tool miri no longer builds.
A follow-up PR to the repository https://github.com/rust-lang/miri is needed to fix the fallout.

cc @Centril, do you think you would have time to do the follow-up work?
If so, that would be great!

cc @Centril, the PR reviewer, and @rust-lang/compiler -- nominating for prioritization.

[RalfJung]

Miri-side fix: https://github.com/rust-lang/miri/pull/860

[JohnTitor]

Could we resolve this by updating Miri?

[RalfJung]

Right now, no, because something broke Miri on macOS and I am not sure what.

[JohnTitor]

Hmm, the build passes now? Oh, I missed https://github.com/rust-lang/miri/pull/862.

[RalfJung]

Breakage is likely caused by https://github.com/rust-lang/rust/pull/62982.

[RalfJung]

Submitted fix: https://github.com/rust-lang/rust/pull/63076

[JohnTitor]

The fixes landed?

[RalfJung]

It did, yes. There are some PRs under review on the rustc side that would break Miri again, but if you want you can update Miri so we'll get one or two nightlies with newer versions.

Btw, for using Miri on CI or so, I recommend a snippet such as:

MIRI_NIGHTLY=nightly-$(curl -s https://rust-lang.github.io/rustup-components-history/x86_64-unknown-linux-gnu/miri)
echo "Installing latest nightly with Miri: $MIRI_NIGHTLY"
rustup default "$MIRI_NIGHTLY"

This way you'll get a working Miri even if the latest nightly does not have one.

[RalfJung]

(In case you open a PR, please Cc/r? me. I won't see it otherwise.)