Remove more BuiltinLintDiag variants - part 4 by GuillaumeGomez · Pull Request #154376 · rust-lang/rust

GuillaumeGomez · 2026-03-25T16:37:51Z

View all comments

Part of #153099.

I wonder if there will be any impact on perf by doing this code all the time. Gonna check.

r? @JonathanBrouwer

rustbot · 2026-03-25T16:37:57Z

JonathanBrouwer is currently at their maximum review capacity.
They may take a while to respond.

GuillaumeGomez · 2026-03-25T16:38:17Z

@bors try @rust-timer queue

Remove more BuiltinLintDiag variants - part 4

JonathanBrouwer

r=me if perf doesn't regress

View changes since this review

rust-bors · 2026-03-25T18:49:07Z

☀️ Try build successful (CI)
Build commit: 15fe654 (15fe654f48f70513a93a7c83747adc01baf1d6af, parent: 8a703520e80d87d4423c01f9d4fbc9e5f6533a02)

rust-timer · 2026-03-25T19:29:22Z

Finished benchmarking commit (15fe654): comparison URL.

Overall result: ❌ regressions - please read the text below

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@bors rollup=never
@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)	2.0%	[0.5%, 3.3%]	13
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary -2.4%, secondary 2.2%)

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)	4.5%	[1.3%, 6.8%]	6
Improvements ✅ (primary)	-2.4%	[-2.4%, -2.4%]	2
Improvements ✅ (secondary)	-4.8%	[-5.1%, -4.4%]	2
All ❌✅ (primary)	-2.4%	[-2.4%, -2.4%]	2

Cycles

Results (primary 2.8%, secondary 5.1%)

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

	mean	range	count
Regressions ❌ (primary)	2.8%	[2.8%, 2.8%]	1
Regressions ❌ (secondary)	5.1%	[2.5%, 7.7%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.8%	[2.8%, 2.8%]	1

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 482.838s -> 482.192s (-0.13%)
Artifact size: 394.91 MiB -> 394.90 MiB (-0.00%)

GuillaumeGomez · 2026-03-25T22:26:56Z

Seems like we're forced to handle the computation only on need, so changed DecorateDiagCompat::Dynamic to make it provide a Session when needed. Let's see if perf is back to normal!

@bors try @rust-timer queue

Remove more BuiltinLintDiag variants - part 4

rust-bors · 2026-03-26T00:38:23Z

☀️ Try build successful (CI)
Build commit: 710c3a7 (710c3a78cc2b99a56947b72d4ff0e45a5e37ad7b, parent: 212ef7770dfad656782207fda799bdae28fc5b7b)

rust-timer · 2026-03-26T01:18:52Z

Finished benchmarking commit (710c3a7): comparison URL.

Overall result: ❌ regressions - please read the text below

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please do so in sufficient writing along with @rustbot label: +perf-regression-triaged. If not, please fix the regressions and do another perf run. If its results are neutral or positive, the label will be automatically removed.

@bors rollup=never
@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)	0.2%	[0.1%, 0.4%]	12
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
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)	3.0%	[2.6%, 3.3%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-5.0%	[-6.9%, -2.5%]	3
All ❌✅ (primary)	-	-	0

Cycles

Results (secondary 5.3%)

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)	5.3%	[2.2%, 9.4%]	3
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 484.064s -> 483.536s (-0.11%)
Artifact size: 396.84 MiB -> 394.94 MiB (-0.48%)

GuillaumeGomez · 2026-03-31T14:42:06Z

Perf regression is smaller now. Good enough @JonathanBrouwer ?

JonathanBrouwer · 2026-04-03T13:52:26Z

@bors r+ rollup=iffy
Rollup=iffy because of the small performance effect, tho should be easy to isolate in a rollup since it's one specific test

rust-bors · 2026-04-03T13:52:29Z

📌 Commit 9dc438e has been approved by JonathanBrouwer

It is now in the queue for this repository.

…o downcast to `Session`

rustbot · 2026-04-03T19:48:34Z

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.

GuillaumeGomez · 2026-04-03T19:49:06Z

@bors r=JonathanBrouwer rollup=iffy

rust-bors · 2026-04-03T19:49:09Z

📌 Commit df848e7 has been approved by JonathanBrouwer

It is now in the queue for this repository.

@JonathanBrouwer

…athanBrouwer Remove more BuiltinLintDiag variants - part 4 Part of rust-lang#153099. I wonder if there will be any impact on perf by doing this code all the time. Gonna check. r? @JonathanBrouwer

Rollup of 10 pull requests Successful merges: - #154376 (Remove more BuiltinLintDiag variants - part 4) - #127534 (feat(core): impl Step for NonZero<u*>) - #153286 (various fixes for scalable vectors) - #153592 (Add `min_adt_const_params` gate) - #154675 (Improve shadowed private field diagnostics) - #154703 (Fix trailing comma in lifetime suggestion for empty angle brackets) - #154653 (Remove rustc_on_unimplemented's append_const_msg) - #154743 (Remove an unused `StableHash` impl.) - #154752 (Add comment to borrow-checker) - #154764 (Add tests for three ICEs that have already been fixed)

Rollup of 5 pull requests Successful merges: - #154376 (Remove more BuiltinLintDiag variants - part 4) - #154731 (llvm: Fix array ABI test to not check equality implementation) - #127534 (feat(core): impl Step for NonZero<u*>) - #154703 (Fix trailing comma in lifetime suggestion for empty angle brackets) - #154776 (Fix ICE in read_discriminant for enums with non-contiguous discriminants)

@JonathanBrouwer

Rollup merge of #154376 - GuillaumeGomez:migrate-diag, r=JonathanBrouwer Remove more BuiltinLintDiag variants - part 4 Part of #153099. I wonder if there will be any impact on perf by doing this code all the time. Gonna check. r? @JonathanBrouwer

Mark-Simulacrum · 2026-04-06T12:10:38Z

Regression in rollup (#154802 (comment)) almost certainly due to this PR. Marking as triaged as I don't think we need to dig further at this time.

rustbot assigned JonathanBrouwer Mar 25, 2026

rustbot added 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 Mar 25, 2026