port lint attributes by mejrs · Pull Request #162811 · rust-lang/rust

mejrs · 2026-09-15T13:17:22Z

Ports the lint attributes. I've kept this as small as possible, but there is a decent amount of clean up/refactoring that can be done afterwards,

r? @JonathanBrouwer @jdonszelmann
cc @Bryntet

rustbot · 2026-09-15T13:17:25Z

Some changes occurred in compiler/rustc_passes/src/check_attr.rs

cc @jdonszelmann, @JonathanBrouwer

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

Some changes occurred in compiler/rustc_attr_ir

cc @jdonszelmann, @JonathanBrouwer

Some changes occurred in compiler/rustc_attr_parsing

cc @jdonszelmann, @JonathanBrouwer

clippy is developed in its own repository. If possible, consider making this change to rust-lang/rust-clippy instead.

cc @rust-lang/clippy

mejrs · 2026-09-15T13:21:15Z

+LL |     let y: u32 = (x?).try_into().unwrap();
+   |                  +  +++++++++++++++++++++


Uh yeah I don't know what's happening here

View changes since the review

JonathanBrouwer · 2026-09-15T13:23:07Z

I'll take a look at this on Friday! Thanks for doing this!

Bryntet · 2026-09-15T13:27:28Z

Thanks for picking this up ❤️

JonathanBrouwer · 2026-09-15T13:34:09Z

cc @cjgillot @petrochenkov in case you'd like to take a look (as reviewers of the original pr #155691)

mejrs · 2026-09-15T13:34:44Z

I'll take a look at this on Friday! Thanks for doing this!

I'll go ahead and cherrypick some changes from this PR then, some things can be split off.

mejrs · 2026-09-15T13:48:32Z

-        #[allow()]
-        { }
-    }
+    fn expr_block() { { } unsafe { } 'a: { } { } { } }


We drop these empty lint attributes, this is nice because when we query for the attribute we know it's non-empty and we can do things like lints.first().unwrap()

View changes since the review

JonathanBrouwer · 2026-09-15T14:10:12Z

Blocked on #162813

mejrs · 2026-09-15T15:58:16Z

@bors try @rust-timer queue

port lint attributes

rust-bors · 2026-09-15T16:59:49Z

☀️ Try build successful (CI)
Build commit: 837b948 (837b9481206c510936be02f4b200f8db8aae1286)
Base parent: 1936d44 (1936d44457352da43b2d740672b940ebc715ac38)

rust-timer · 2026-09-15T17:47:26Z

Finished benchmarking commit (837b948): comparison URL.

Overall result: ❌✅ regressions and improvements - BENCHMARK(S) FAILED

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@bors rollup=never rustc-perf
@rustbot label: -S-waiting-on-perf +perf-regression

❗ ❗ ❗ ❗ ❗
Warning ⚠️: The following benchmark(s) failed to build:

image-0.25.6
Job failure

❗ ❗ ❗ ❗ ❗

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	0.6%	[0.2%, 3.5%]	197
Regressions ❌ (secondary)	0.9%	[0.1%, 5.8%]	170
Improvements ✅ (primary)	-36.2%	[-77.2%, -10.4%]	4
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.1%	[-77.2%, 3.5%]	201

Max RSS (memory usage)

Results (primary -7.1%, secondary -1.8%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	1.6%	[0.6%, 3.1%]	3
Regressions ❌ (secondary)	3.5%	[2.4%, 4.1%]	3
Improvements ✅ (primary)	-20.2%	[-22.6%, -17.8%]	2
Improvements ✅ (secondary)	-7.1%	[-9.4%, -3.6%]	3
All ❌✅ (primary)	-7.1%	[-22.6%, 3.1%]	5

Cycles

Results (primary -7.6%, secondary 2.7%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	3.0%	[1.3%, 4.3%]	11
Regressions ❌ (secondary)	3.1%	[2.0%, 5.2%]	16
Improvements ✅ (primary)	-36.8%	[-77.7%, -10.0%]	4
Improvements ✅ (secondary)	-4.5%	[-4.5%, -4.5%]	1
All ❌✅ (primary)	-7.6%	[-77.7%, 4.3%]	15

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 495.925s -> 496.275s (0.07%)
Artifact size: 406.90 MiB -> 407.07 MiB (0.04%)

mejrs · 2026-09-15T18:33:02Z

@bors try @rust-timer queue

port lint attributes

blyxyas · 2026-09-15T19:28:50Z

Does this still filter allow-ed lints? I'm not sure if we have tests for lint filtering.

rust-bors · 2026-09-15T19:38:58Z

☀️ Try build successful (CI)
Build commit: 963f3c5 (963f3c572f18e6b9322ac395768e693238957bad)
Base parent: 1936d44 (1936d44457352da43b2d740672b940ebc715ac38)

mejrs · 2026-09-15T21:01:53Z

The job test-aarch64-gnu-llvm-21-1 failed! Check out the build log: (web) (plain enhanced) (plain)

when I was working on lint attrs, I remember also running into this target having errors

I did not bless pretty tests (they don't matter here, the second commit is just for benchmarking)

@JonathanBrouwer

…nBrouwer,petrochenkov Pre lint port cleanups Some minor changes split off from rust-lang#162811, to make that a bit easier to review. cc @JonathanBrouwer

rust-timer · 2026-09-15T21:45:26Z

Finished benchmarking commit (963f3c5): comparison URL.

Overall result: ❌✅ regressions and improvements - BENCHMARK(S) FAILED

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@bors rollup=never rustc-perf
@rustbot label: -S-waiting-on-perf +perf-regression

❗ ❗ ❗ ❗ ❗
Warning ⚠️: The following benchmark(s) failed to build:

image-0.25.6
Job failure

❗ ❗ ❗ ❗ ❗

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	0.5%	[0.1%, 2.8%]	170
Regressions ❌ (secondary)	0.8%	[0.1%, 4.7%]	155
Improvements ✅ (primary)	-36.3%	[-77.2%, -10.6%]	4
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-0.3%	[-77.2%, 2.8%]	174

Max RSS (memory usage)

Results (primary -9.2%, secondary -1.6%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	1.8%	[0.6%, 3.0%]	2
Regressions ❌ (secondary)	4.0%	[2.5%, 4.9%]	3
Improvements ✅ (primary)	-20.2%	[-22.6%, -17.8%]	2
Improvements ✅ (secondary)	-7.2%	[-9.5%, -3.7%]	3
All ❌✅ (primary)	-9.2%	[-22.6%, 3.0%]	4

Cycles

Results (primary -10.3%, secondary 3.0%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	2.9%	[2.0%, 4.1%]	8
Regressions ❌ (secondary)	3.3%	[1.8%, 5.2%]	18
Improvements ✅ (primary)	-36.8%	[-77.7%, -10.1%]	4
Improvements ✅ (secondary)	-3.4%	[-3.4%, -3.4%]	1
All ❌✅ (primary)	-10.3%	[-77.7%, 4.1%]	12

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 495.925s -> 499.736s (0.77%)
Artifact size: 406.90 MiB -> 407.72 MiB (0.20%)

mejrs · 2026-09-15T22:07:10Z

Does this still filter allow-ed lints? I'm not sure if we have tests for lint filtering.

What do you mean?

mejrs · 2026-09-15T22:11:45Z

woops, here we go again

    thread 'rustc' (290057) panicked at /rustc-dev/963f3c572f18e6b9322ac395768e693238957bad/compiler/rustc_middle/src/query/on_disk_cache.rs:662:9:
    cannot decode `AttrId` with `CacheDecoder`

@JonathanBrouwer

Rollup merge of #162813 - mejrs:pre_lint_cleanups, r=JonathanBrouwer,petrochenkov Pre lint port cleanups Some minor changes split off from #162811, to make that a bit easier to review. cc @JonathanBrouwer

blyxyas · 2026-09-16T09:03:13Z

What do you mean?

I mean, is the output from the skippable_lints query still faithful to the lint attributes?

Bryntet · 2026-09-16T09:40:28Z

What do you mean?

I mean, is the output from the skippable_lints query still faithful to the lint attributes?

That query uses
tcx.shallow_lint_levels_on(hir::CRATE_OWNER_ID); to know about lints

which means that as long as shallow_lint_levels_on is consistent, it shouldn't break.

And we have plenty of testing for that

rustbot · 2026-09-16T10:35:31Z

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.

rustbot assigned JonathanBrouwer Sep 15, 2026

mejrs commented Sep 15, 2026

View reviewed changes

mejrs force-pushed the port_lint_check branch from 5f087e2 to c90513f Compare September 15, 2026 13:33

JonathanBrouwer mentioned this pull request Sep 15, 2026

Re-port lint attributes to attribute parsers #155691

Closed

petrochenkov self-assigned this Sep 15, 2026

mejrs commented Sep 15, 2026

View reviewed changes

mejrs mentioned this pull request Sep 15, 2026

Pre lint port cleanups #162813

Merged

JonathanBrouwer added the S-blocked Status: Blocked on something else such as an RFC or other implementation work. label Sep 15, 2026