rustc 1.76 required by firefox 127

[Rico Tzschichholz]

Firefox 127+ requires rustc 1.76 to build¹².

The beta phase for Firefox 127.0 begins on 2024-05-13 and release candidates will be available from 2024-06-11.

Eventually Thunderbird will need an updated rust toolchain as well.

We will need these in all supported releases of Ubuntu: focal, jammy, mantic, noble.

¹ https://bugzilla.mozilla.org/show_bug.cgi?id=1890935
² https://phabricator.services.mozilla.com/D207239

Rust toolchain upgrades are usually relatively safe from a FTBFS point of view, since new releases are subjected to a crater run, crater being a tool that compiles the entirety of the crates.io packages.

[Zixing Liu (liushuyu-011)]

The rustc toolchain update is currently experiencing a delay due to LP: #2052985 and LP: #2054748.
Unfortunately, they failed to make it to Noble and are now targeting Oracular.

Due to how the backport process works in the Rust toolchain packages, Rust 1.76 in F, J, M and N will be available after the upload to Oracular.

[Rico Tzschichholz (ricotz)]

Thanks! I see that rustc-1.76 is available in oracular now. Is there an ETA for the backported packages?

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.