bug#62064: Why is only rust-1.60 exported when 1.65 is defined?

[Jonas Møller]

Hi Guix! The rust.scm file says

;;; Note: Only the latest versions of Rust are supported and tested.  The
;;; intermediate rusts are built for bootstrapping purposes and should not
;;; be relied upon.  This is to ease maintenance and reduce the time
;;; required to build the full Rust bootstrap chain.
;;;
;;; Here we take the latest included Rust, make it public, and re-enable tests
;;; and extra components such as rustfmt.

And then proceeds to define-public rust as rust-1.60, and I was wondering if there's any particular reason why a year-old version is used rather than the 1.65 version. This seems like a mistake, given that the comment claims that the "latest included Rust" should be made public.

This is especially troublesome for Rust on Guix because of both how fast its ecosystem moves onto new language/tooling features, and because using rustup (the solution for this on other slow-moving distros) relies on pre-built executables that don't work out-of-the-box on Guix.

— Mvh Jonas Møller