Produce packaging guidelines

[brson]

Summarize what we've learned into some general guidelines for packagers.

Potential topics:

• Maintaining independently-bootstrapped Rust compilers.
• Packaging Cargo libraries / applications
• Generating offline docs

re https://internals.rust-lang.org/t/perfecting-rust-packaging-the-plan/2767

[steveklabnik]

At what point are we far enough along that I should start work on this?

[steveklabnik]

@brson ping! Have we gotten far enough for me to write these docs yet, and how would I go about finding that information?

[brson]

We could probably produce some guidelines now. But it would take some investigation to figure out both what packaging-related features we're providing and what packagers are actually doing in practice, and to make sense of it. It's all pretty fuzzy to me still.

I could probably spend a day collecting notes together, then bounce them off our packagers to see if they make sense. Low priority still.

[oconnor663]

Lots of packaging discussion at https://internals.rust-lang.org/t/beta-testing-rustup-rs/3316/188

More Arch Linux specific discussion at https://aur.archlinux.org/packages/rustup/?comments=all

[cuviper]

I was just asking @brson for a judgement whether it would be kosher for distros to patch 1.15.0 with #39466, changing a public interface. He indicated discomfort. This particular point is moot if there's going to be a 1.15.1 point release, but there's a larger question here.

What would the Rust Project find acceptable for downstream builders to change? I'd expect general bug fixing to be allowable, but changing a public interface gets questionable, I agree. Do we need to say anything more than that?

Interface questions could also come up if there's ever a separate compiler implemented, say gcc-rust.

Of course, the license permits pretty much any change you like, but maybe there's some trademark muscle to flex behind this policy, if needed. Or maybe you just grumble about out-of-spec implementations.

[steveklabnik]

Triage: tagging as T-infra as well; docs team is happy to help here, but we'd need you all to get a rough draft together.

[steveklabnik]

tagging as p-low, @rust-lang/infra , let the docs team know when you want to collaborate on this