Auto generate list of supported targets from rustup

Question

Auto generate list of supported targets from rustup

gnzlbg opened this issue 5 years ago · comments

Manually maintaining the list of supported targets has never really properly worked. People remember to add new targets every now and then, but nobody remembers to remove old targets.

We should "somehow" use rustup to automatically generate a list of targets, and the components they support. We can then assign them tier1-3 labels manually, but should ideally get a warning / error when a target disappear or a new target each added.

Maybe rust-lang/rust could record the tier of each build artifact, and rustup could allow querying this, so that no manual effort is necessary.

Also note that this reveals the first issue, targets are toolchain dependent, and not all toolchains support all targets. People are probably also interested in both: all targets that Rust supports, and all targets that my toolchain supports.

gnzlbg commented 5 years ago

Thanks!

gnzlbg · Answer 1 · Tue Feb 12 2019 18:00:33 GMT+0800 (China Standard Time)

Maintainers of tools based on Rust, like compiler-explorer (aka godbolt), have issues because they cannot see which targets are available for which toolchains, e.g., compiler-explorer/compiler-explorer#1271 (comment).

Daniel Silverstone · Answer 2 · Mon May 27 2019 05:09:04 GMT+0800 (China Standard Time)

This would not need rustup support since the channel toml files are pretty sensible and form a stable interface.

I would be interested in helping to separate out into a vaguely supportable (though still 0.x) crate for managing manifest files if there was interest in sharing the work.

gnzlbg · Answer 3 · Mon May 27 2019 06:22:44 GMT+0800 (China Standard Time)

Are there channel toml files for each Rust toolchain release somewhere?

Daniel Silverstone · Answer 4 · Mon May 27 2019 14:37:42 GMT+0800 (China Standard Time)

Yes. I've submitted a PR which begins to document this (descriptivist not prescriptivist though, so errors are likely) -- https://static.rust-lang.org/dist/channel-rust-X.YY.Z.toml should exist for any X.YY.Z which was released. It's possible the older v2 manifests as these are called may not be present.

Daniel Silverstone · Answer 5 · Mon May 27 2019 14:38:06 GMT+0800 (China Standard Time)

For reference, the PR is here: #227

Simon Sapin · Answer 6 · Tue Aug 20 2019 06:45:33 GMT+0800 (China Standard Time)

@gnzlbg Why close this? #227 is a good step to figure out how to fix this issue, but still looks very relevant. rustc --print target-list has 135 targets in today’s Nightly, but tiers.yaml in this repository lists much fewer: #247 (comment)

gnzlbg · Answer 7 · Tue Aug 20 2019 15:06:54 GMT+0800 (China Standard Time)

@SimonSapin i closed this because my use case (installing all available targets) was resolved in the mean time (rustup target add all). If someone wants to print the list of all available targets re-opening sounds good.

Toshiki Teramura · Answer 8 · Thu Jan 02 2020 00:12:21 GMT+0800 (China Standard Time)

https://forge.rust-lang.org/release/platform-support.html

I find a duplicated line. Is this issue responsible? or should I create another issue?

XAMPPRocky · Answer 9 · Thu Jan 02 2020 00:37:19 GMT+0800 (China Standard Time)

@termoshtt It would best if you could create a PR correcting it. The file is in src/release/platform-support.md

Eric Huss · Answer 10 · Fri Oct 27 2023 01:34:04 GMT+0800 (China Standard Time)

I'm going to close this as effectively resolved. The target-tier documentation now lives in rust-lang/rust, and there is validation to ensure that the list is in sync with rustc. It doesn't validate that entries are in the correct tier, but I don't think that can be done from a practical sense (since the tier is driven by CI), though that could possibly be done with metadata in the target spec.