> There's "no reason" why the rustc build should depend on cargo,

rustc is a Rust project. Cargo is a build system for Rust projects.

> this makes it way harder than it should be to keep rustc support up-to-date in any distro

I am not aware of distro maintainers complaining about this, or at least, not any time in the last few years. Do you have some context to share? We want distros to have a good experience.

Debian unstable (IIRC) updated Firefox a couple weeks late because cargo got a couple of new dependencies and nobody added them to the Debian repos. This is because they forbid static linking, so there are hundreds of packages of popular Rust crates compiled as shared libraries. Even worse, some of them have multiple variants, for various combinations of features.

Sure. This is one instance of this happening, and it was fixed, it just took some work. Nobody even filed an upstream bug. This isn’t something exclusive to Rust. It’s almost arguably more due to the way that browsers are treated as an exemption from distro packaging policies (which I appreciate, personally.)

That’s a Debian issue. They’re trying to foist a dependency management strategy intended for C on a different language with a different strategy