rustuphas a mechanism for self-updating, which triggers whenever you request it to install a new toolchain. This is annoying to have happen in CI though, since it increases build time for no benefit (both the check itself, and the eventual update if rustup deems it necessary).
So let's disable this!
Since this is a behavioural change, it could be considered a breaking change, though I will argue that it isn't, people shouldn't need to update rustup itself during a build (rustup update to fetch a newer rustc/cargo still works fine).
Description
rustuphas a mechanism for self-updating, which triggers whenever you request it to install a new toolchain. This is annoying to have happen in CI though, since it increases build time for no benefit (both the check itself, and the eventual update if rustup deems it necessary).So let's disable this!
Since this is a behavioural change, it could be considered a breaking change, though I will argue that it isn't, people shouldn't need to update
rustupitself during a build (rustup updateto fetch a newerrustc/cargostill works fine).Related issue:
https://github.com/actions/runner-images/issues/246, the proposed workaround in there (
--no-self-update) wouldn't be necessary any more.Check list