Run clippy on cg_gcc in CI #149458

GuillaumeGomez · 2025-11-29T17:29:21Z

This is to prevent this issue: in cg_gcc repository, we run clippy on our code but not in here, which can create issues.

cc @antoyo
r? @Kobzol

rustbot · 2025-11-29T17:29:26Z

Kobzol is not on the review rotation at the moment.
They may take a while to respond.

antoyo · 2025-11-29T17:31:24Z

src/ci/docker/host-x86_64/x86_64-gnu-gcc/Dockerfile

 --set llvm.libzstd=true \
 --set 'rust.codegen-backends=[\"llvm\",\"gcc\"]'
-ENV SCRIPT python3 ../x.py \
+ENV SCRIPT python3 ../x.py --stage 2 clippy compiler/rustc_codegen_gcc && \


Does this test both with and without --no-default-features?

No it doesn't. I can add that as a follow-up in the clippy rule.

It would be nice since the above issue would only happens without the master feature.

GuillaumeGomez · 2025-11-29T22:05:34Z

Fixed bootstrap tests and CI is happy. :)

Kobzol

So, I'm a bit confused by this 😅 We have been running Clippy on cg_gcc on CI since January 2025 (#135478). So this PR probably doesn't do exactly what you expect it to.

#149425 was blocked exactly because we run Clippy on cg_gcc in this repository, otherwise it wouldn't fail.

We could ensure that cg_gcc's Clippy version and this repo's Clippy version will stay more up-to-date, or we can change the Clippy configuration in this repo, if needed. But other than that, if we run Clippy on cg_gcc, sometimes the Clippy update will break if there are new lints triggered in cg_gcc, that's just how it is. This does not happen so much for the compiler and library, because they only apply a subset of Clippy lints. While cg_gcc is configured to -Dwarnings in this repository. This was ~~prophesized~~ expected.

View changes since this review

GuillaumeGomez · 2025-12-06T20:29:20Z

I suppose it's fine if updating clippy triggers new lints in cg_gcc, no?

Kobzol · 2025-12-06T20:45:05Z

As long as it doesn't happen too often and isn't too annoying to fix, I would say that it is fine, yes. But it would be better to ask the people who do the Clippy syncs :)

GuillaumeGomez · 2025-12-06T20:50:28Z

Fair enough!

@flip1995 would it be ok if we deny clippy warnings in cg_gcc, potentially meaning that clippy syncs will involve fixing these new warnings as well?

antoyo · 2025-12-06T21:01:23Z

So, I'm a bit confused by this 😅 We have been running Clippy on cg_gcc on CI since January 2025 (#135478). So this PR probably doesn't do exactly what you expect it to.

So, what's probably missing is running clippy without the default features, then. That is what I noticed here.

flip1995 · 2025-12-08T12:57:58Z

Yes that is fine. I've already been doing this

since January 2025

(apparently). I think I had to fix something twice in cg_gcc since then. This also really helps to detect bugs in Clippy during the sync! So feel free to adjust the configuration in this repo to be as close as possible with the one in the cg_gcc repo.

The only thing I can't promise is that the fixes done with the Clippy version in this repo won't conflict with what Clippy sees in the cg_gcc repo. But I don't think there will be a lot of conflicts in this direction, as Clippy in this repo is always the newest possible version.

rustbot · 2025-12-09T11:23:38Z

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

Kobzol · 2025-12-09T11:30:01Z

src/bootstrap/src/core/build_steps/clippy.rs


    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
-        run.alias("rustc_codegen_gcc")
+        run.alias("rustc_codegen_gcc").path("compiler/rustc_codegen_gcc")


I specifically got rid of this recently, as having subpaths of the compiler directory was causing weird behavior and conflicts with x <something> compiler. Do you need it for something specific?

I was completely unable to figure out how to run clippy on cg_gcc (well until I looked at the bootstrap source code). Wouldn't it be better to fix the conflict issues instead because having to look at bootstrap source code to understand how to run a command is really bad. :-/

That would require rewriting large parts of bootstrap xD I could swear that there way a way to list all bootstrap steps for a given command 🤔 If not, it would be nice to have.

Fine fine, removing this change. But please note I'm very sad about it.

GuillaumeGomez · 2025-12-09T14:22:01Z

CI failed so all good. Sending fix for cg_gcc now. :)

rustbot · 2025-12-09T14:42:33Z

Some changes occurred in compiler/rustc_codegen_gcc

cc @antoyo, @GuillaumeGomez

antoyo · 2025-12-09T15:13:41Z

Is there some way to make it more obvious in the error message that these errors come with --no-default-features so that people understand more easily where they come from?
Would that be helpful?

GuillaumeGomez · 2025-12-09T16:12:18Z

Is there some way to make it more obvious in the error message that these errors come with --no-default-features so that people understand more easily where they come from? Would that be helpful?

Hum... Except adding a println! right before I make the call, I don't see how we can do. Sounds like something for a follow-up. :p

Kobzol · 2025-12-09T16:51:59Z

You can r=me with or without the print (I agree that a print should be enough).

GuillaumeGomez · 2025-12-09T16:53:17Z

Let's add a print then.

GuillaumeGomez · 2025-12-09T17:02:08Z

Added the print. Let's go then.

@bors r=kobzol rollup

bors · 2025-12-09T17:02:11Z

📌 Commit 06500aa has been approved by kobzol

It is now in the queue for this repository.

rust-log-analyzer · 2025-12-09T17:13:15Z

The job aarch64-gnu-llvm-20-2 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

   Compiling rustc_parse v0.0.0 (/checkout/compiler/rustc_parse)
[RUSTC-TIMING] rustc_session test:false 24.082
   Compiling rustc_next_trait_solver v0.0.0 (/checkout/compiler/rustc_next_trait_solver)

Session terminated, killing shell...::group::Clock drift check
  local time: Tue Dec  9 17:13:03 UTC 2025
##[error]The runner has received a shutdown signal. This can happen when the runner service is stopped, or a manually started runner is canceled.
  network time: Tue, 09 Dec 2025 17:13:03 GMT
##[endgroup]
 ...killed.

…bzol Run clippy on cg_gcc in CI This is to prevent [this issue](rust-lang#149449 (comment)): in cg_gcc repository, we run clippy on our code but not in here, which can create issues. cc `@antoyo` r? `@Kobzol`

Rollup of 6 pull requests Successful merges: - #147602 (Deduplicate higher-ranked lifetime capture errors in impl Trait) - #147725 (Remove -Zoom=panic) - #148491 ( Correctly provide suggestions when encountering `async fn` with a `dyn Trait` return type) - #148717 (Point at span within local macros even when error happens in nested external macro) - #149458 (Run clippy on cg_gcc in CI) - #149816 (Make typo in field and name suggestions verbose) r? `@ghost` `@rustbot` modify labels: rollup

…bzol Run clippy on cg_gcc in CI This is to prevent [this issue](rust-lang#149449 (comment)): in cg_gcc repository, we run clippy on our code but not in here, which can create issues. cc ``@antoyo`` r? ``@Kobzol``

…bzol Run clippy on cg_gcc in CI This is to prevent [this issue](rust-lang#149449 (comment)): in cg_gcc repository, we run clippy on our code but not in here, which can create issues. cc ```@antoyo``` r? ```@Kobzol```

Rollup of 12 pull requests Successful merges: - #147602 (Deduplicate higher-ranked lifetime capture errors in impl Trait) - #147725 (Remove -Zoom=panic) - #148294 (callconv: fix mips64 aggregate argument passing for C FFI) - #148491 ( Correctly provide suggestions when encountering `async fn` with a `dyn Trait` return type) - #149417 (tidy: Detect outdated workspaces in workspace list) - #149458 (Run clippy on cg_gcc in CI) - #149679 (Restrict spe_acc to PowerPC SPE targets) - #149781 (Don't suggest wrapping attr in unsafe if it may come from proc macro) - #149795 (Use `let`...`else` instead of `match foo { ... _ => return };` and `if let ... else return` in std) - #149816 (Make typo in field and name suggestions verbose) - #149824 (Add a regression test for issue 145748) - #149826 (compiletest: tidy up `adb_path`/`adb_test_dir` handling) r? `@ghost` `@rustbot` modify labels: rollup

Rollup of 10 pull requests Successful merges: - #147725 (Remove -Zoom=panic) - #148294 (callconv: fix mips64 aggregate argument passing for C FFI) - #148491 ( Correctly provide suggestions when encountering `async fn` with a `dyn Trait` return type) - #149458 (Run clippy on cg_gcc in CI) - #149679 (Restrict spe_acc to PowerPC SPE targets) - #149781 (Don't suggest wrapping attr in unsafe if it may come from proc macro) - #149795 (Use `let`...`else` instead of `match foo { ... _ => return };` and `if let ... else return` in std) - #149816 (Make typo in field and name suggestions verbose) - #149824 (Add a regression test for issue 145748) - #149826 (compiletest: tidy up `adb_path`/`adb_test_dir` handling) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of #149458 - GuillaumeGomez:clippy-cg_gcc, r=kobzol Run clippy on cg_gcc in CI This is to prevent [this issue](#149449 (comment)): in cg_gcc repository, we run clippy on our code but not in here, which can create issues. cc ````@antoyo```` r? ````@Kobzol````

Rollup of 10 pull requests Successful merges: - rust-lang/rust#147725 (Remove -Zoom=panic) - rust-lang/rust#148294 (callconv: fix mips64 aggregate argument passing for C FFI) - rust-lang/rust#148491 ( Correctly provide suggestions when encountering `async fn` with a `dyn Trait` return type) - rust-lang/rust#149458 (Run clippy on cg_gcc in CI) - rust-lang/rust#149679 (Restrict spe_acc to PowerPC SPE targets) - rust-lang/rust#149781 (Don't suggest wrapping attr in unsafe if it may come from proc macro) - rust-lang/rust#149795 (Use `let`...`else` instead of `match foo { ... _ => return };` and `if let ... else return` in std) - rust-lang/rust#149816 (Make typo in field and name suggestions verbose) - rust-lang/rust#149824 (Add a regression test for issue 145748) - rust-lang/rust#149826 (compiletest: tidy up `adb_path`/`adb_test_dir` handling) r? `@ghost` `@rustbot` modify labels: rollup

rustbot assigned Kobzol Nov 29, 2025

antoyo reviewed Nov 29, 2025

View reviewed changes