Move track_caller on closures gating to attribute parsing by mejrs · Pull Request #162075 · rust-lang/rust

mejrs · 2026-08-31T17:13:26Z

I noticed this while reviewing #161958

rustbot · 2026-08-31T17:13:31Z

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_parsing

cc @jdonszelmann, @JonathanBrouwer

rustbot · 2026-08-31T17:13:33Z

r? @TaKO8Ki

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JonathanBrouwer · 2026-08-31T19:40:03Z

                }
-                if is_closure
-                    && !tcx.features().closure_track_caller()
-                    && !attr_span.allows_unstable(sym::closure_track_caller)


This does technically make the feature gate slightly stricter, since we were previously checking for attr_span.allows_unstable(sym::closure_track_caller).
I think that's fine though, I'm not expecting anyone to be relying on this, and we can add it back if anyone complains :)

View changes since the review

JonathanBrouwer · 2026-08-31T19:48:29Z

        if self.tcx.features().async_fn_track_caller()
            && let Some(attrs) = self.attrs.get(&outer_hir_id.local_id)
-            && find_attr!(*attrs, TrackCaller(_))
+            && let Some(t) = attrs.iter().find(|a| {


Kinda sad that we need to expand the find_attr! here but this code is so much better than whatever was going on before, so thanks!

View changes since the review

JonathanBrouwer

@bors r+ rollup

View changes since this review

rust-bors · 2026-08-31T19:48:55Z

📌 Commit e18a012 has been approved by JonathanBrouwer

It is now in the queue for this repository.

… r=JonathanBrouwer Move track_caller on closures gating to attribute parsing I noticed this while reviewing rust-lang#161958

…uwer Rollup of 12 pull requests Successful merges: - #162045 (`rust-analyzer` subtree update) - #162077 (compiler-builtins subtree update) - #137720 (support `#[target_feature(enable = ...)]` on `#[naked]` functions) - #160534 (stabilize smart pointer map functions) - #160551 (mir_build: Clearly distinguish or/refutable/irrefutable patterns during match lowering) - #161929 (explicitly track inherent const generic args kind) - #162063 (Switch dist-aarch64-linux to EC2 and update dist-x86_64-linux) - #161937 (A series of Polonius Alpha refactors) - #162014 (Move more `rustdoc-html` tests using `--test` into the right folder) - #162051 (`rustc_feature` cleanups) - #162055 (remove `_{style}` recovery for diagnostic structs) - #162075 (Move track_caller on closures gating to attribute parsing)

… r=JonathanBrouwer Move track_caller on closures gating to attribute parsing I noticed this while reviewing rust-lang#161958

…uwer Rollup of 16 pull requests Successful merges: - #137720 (support `#[target_feature(enable = ...)]` on `#[naked]` functions) - #160534 (stabilize smart pointer map functions) - #160551 (mir_build: Clearly distinguish or/refutable/irrefutable patterns during match lowering) - #160989 (Make sin, cos, exp, exp2, log, log2, log10 generic) - #161861 (mir_build: Clarify parts of if-condition lowering) - #161929 (explicitly track inherent const generic args kind) - #162040 (bootstrap: stage0 to cbae9b4) - #162063 (Switch dist-aarch64-linux to EC2 and update dist-x86_64-linux) - #161353 (Add test for parallel compiler reproducible build) - #161937 (A series of Polonius Alpha refactors) - #162051 (`rustc_feature` cleanups) - #162055 (remove `_{style}` recovery for diagnostic structs) - #162075 (Move track_caller on closures gating to attribute parsing) - #162079 (std: implement `File::fsync` for Hermit) - #162097 (Deduplicate `InstrumentFnAttr`) - #162115 (fix typo in feature documentation)

Rollup merge of #162075 - mejrs:track_caller_closure_gating, r=JonathanBrouwer Move track_caller on closures gating to attribute parsing I noticed this while reviewing #161958

rust-timer · 2026-09-01T19:50:07Z

Finished benchmarking commit (b4fba3d): comparison URL.

Overall result: ✅ improvements - no action needed

Benchmarking means the PR may be perf-sensitive. Consider adding rollup=never if this change is not fit for rolling up.

@rustbot label: -S-waiting-on-perf -perf-regression

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
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.4%	[-0.4%, -0.4%]	1
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (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)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-1.8%	[-2.3%, -0.9%]	4
All ❌✅ (primary)	-	-	0

Cycles

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Binary size

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Bootstrap: missing data
Artifact size: 400.59 MiB -> 400.61 MiB (0.00%)

…uwer Rollup of 16 pull requests Successful merges: - rust-lang/rust#137720 (support `#[target_feature(enable = ...)]` on `#[naked]` functions) - rust-lang/rust#160534 (stabilize smart pointer map functions) - rust-lang/rust#160551 (mir_build: Clearly distinguish or/refutable/irrefutable patterns during match lowering) - rust-lang/rust#160989 (Make sin, cos, exp, exp2, log, log2, log10 generic) - rust-lang/rust#161861 (mir_build: Clarify parts of if-condition lowering) - rust-lang/rust#161929 (explicitly track inherent const generic args kind) - rust-lang/rust#162040 (bootstrap: stage0 to cbae9b4cae2b108f6a3d18cfe6075714bb739463) - rust-lang/rust#162063 (Switch dist-aarch64-linux to EC2 and update dist-x86_64-linux) - rust-lang/rust#161353 (Add test for parallel compiler reproducible build) - rust-lang/rust#161937 (A series of Polonius Alpha refactors) - rust-lang/rust#162051 (`rustc_feature` cleanups) - rust-lang/rust#162055 (remove `_{style}` recovery for diagnostic structs) - rust-lang/rust#162075 (Move track_caller on closures gating to attribute parsing) - rust-lang/rust#162079 (std: implement `File::fsync` for Hermit) - rust-lang/rust#162097 (Deduplicate `InstrumentFnAttr`) - rust-lang/rust#162115 (fix typo in feature documentation)

Move track_caller on closures gating to attribute parsing

e18a012

rustbot added A-attributes Area: Attributes (`#[…]`, `#![…]`) S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Aug 31, 2026

rustbot assigned TaKO8Ki Aug 31, 2026

JonathanBrouwer reviewed Aug 31, 2026

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JonathanBrouwer approved these changes Aug 31, 2026

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rust-bors Bot added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Aug 31, 2026

JonathanBrouwer mentioned this pull request Aug 31, 2026

Rollup of 10 pull requests #162087

Closed

GuillaumeGomez mentioned this pull request Aug 31, 2026

Rollup of 11 pull requests #162088

Closed

JonathanBrouwer mentioned this pull request Aug 31, 2026

Rollup of 12 pull requests #162089

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jhpratt added a commit to jhpratt/rust that referenced this pull request Sep 1, 2026

Rollup merge of rust-lang#162075 - mejrs:track_caller_closure_gating,…

218fba1

… r=JonathanBrouwer Move track_caller on closures gating to attribute parsing I noticed this while reviewing rust-lang#161958

jhpratt mentioned this pull request Sep 1, 2026

Rollup of 12 pull requests #162100

Closed

jhpratt added a commit to jhpratt/rust that referenced this pull request Sep 1, 2026

Rollup merge of rust-lang#162075 - mejrs:track_caller_closure_gating,…

51260d4

… r=JonathanBrouwer Move track_caller on closures gating to attribute parsing I noticed this while reviewing rust-lang#161958

jhpratt mentioned this pull request Sep 1, 2026

Rollup of 11 pull requests #162101

Closed

JonathanBrouwer assigned JonathanBrouwer and unassigned TaKO8Ki Sep 1, 2026

JonathanBrouwer mentioned this pull request Sep 1, 2026

Rollup of 16 pull requests #162117

Merged

rust-bors Bot merged commit dbfa398 into rust-lang:main Sep 1, 2026
13 checks passed

rustbot added this to the 1.100.0 milestone Sep 1, 2026

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Move track_caller on closures gating to attribute parsing - #162075

Move track_caller on closures gating to attribute parsing#162075
rust-bors[bot] merged 1 commit into
rust-lang:mainfrom
mejrs:track_caller_closure_gating

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