rustup no longer installs the active toolchain if it's not installed

[Ravencentric]

Description

rustup 1.28 just released with a breaking change in its behavior, i.e., it will no longer automatically install the active toolchain if it is not installed.

This means that the instructions in Building Rust wheels are now outdated.

Build log

https://github.com/Ravencentric/rnzb/actions/runs/13641450202/job/38132064949
https://gist.github.com/Ravencentric/aa7572e9b4a1262fbf7ada5165907aff#file-cibuildwheel-issues-2303-txt

CI config

https://github.com/Ravencentric/rnzb/blob/82921ea28f3f32fef6df875ae4cae7f483c0bd42/.github/workflows/release.yml

[Czaki]

Oh. This is why my CI was broken yesterday. So since now there is a need to manually parse the content of rust-toolchain.toml

[henryiii]

I believe this is fixed in today's 1.28.1? https://github.com/rust-lang/rustup/blob/master/CHANGELOG.md

[Ravencentric]

Yep. This issue and the related PR can be closed now.