add FCW to invalid `#[should_panic]` and `#[ignore]` #150416

Bryntet · 2025-12-27T00:29:42Z

this fixes #143799

rustbot · 2025-12-27T00:29:46Z

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

rustbot · 2025-12-27T00:29:48Z

rustbot has assigned @jackh726.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

Bryntet · 2025-12-27T00:29:59Z

r? @JonathanBrouwer

JonathanBrouwer · 2025-12-27T06:31:29Z

@rustbot author
This approach may not work because the test attribute has already expanded at this stage

rustbot · 2025-12-27T06:31:34Z

Reminder, once the PR becomes ready for a review, use @rustbot ready.

rustbot · 2025-12-31T15:53:09Z

Some changes occurred in compiler/rustc_hir/src/attrs

cc @jdonszelmann

Some changes occurred in compiler/rustc_attr_parsing

cc @jdonszelmann

JonathanBrouwer · 2026-01-01T13:57:23Z

@bors try @rust-timer queue

add FCW to `#[should_panic]` on fn without `#[test]` attribute

compiler/rustc_attr_parsing/src/attributes/codegen_attrs.rs

compiler/rustc_attr_parsing/src/attributes/rustc_internal.rs

compiler/rustc_builtin_macros/src/test.rs

JonathanBrouwer · 2026-01-01T14:04:47Z

compiler/rustc_passes/src/errors.rs

+    #[primary_span]
+    pub attr_span: Span,
+    #[warning]
+    pub warning: bool,


Is there a reason #[warning] is configurable here?
I think this can just always be a warning

(you can do this by applying #[warning] to the struct)

this is what all the other FCW in rustc_passes/messages.ftl do AFAICT

Afaik you should just be able to put #[warning] on the struct for the same effect

compiler/rustc_passes/src/errors.rs

rust-bors · 2026-01-01T16:24:36Z

☀️ Try build successful (CI)
Build commit: bcd914a (bcd914a802a15c7ff31dde1b27ac69f61014233e, parent: b49c7d784e96216e1cb709824629f5d53bc73201)

rust-timer · 2026-01-01T17:05:36Z

Finished benchmarking commit (bcd914a): comparison URL.

Overall result: ❌✅ regressions and improvements - 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)	0.3%	[0.1%, 0.5%]	8
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.0%	[-0.0%, -0.0%]	1
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary -1.9%, secondary 3.8%)

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)	3.8%	[3.8%, 3.8%]	1
Improvements ✅ (primary)	-1.9%	[-1.9%, -1.9%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-1.9%	[-1.9%, -1.9%]	1

Cycles

Results (primary -8.5%, secondary -15.1%)

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)	5.8%	[5.8%, 5.8%]	1
Improvements ✅ (primary)	-8.5%	[-13.0%, -2.6%]	10
Improvements ✅ (secondary)	-17.0%	[-27.5%, -3.0%]	11
All ❌✅ (primary)	-8.5%	[-13.0%, -2.6%]	10

Binary size

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

Bootstrap: 476.873s -> 475.466s (-0.30%)
Artifact size: 390.81 MiB -> 390.85 MiB (0.01%)

JonathanBrouwer · 2026-01-08T13:38:24Z

@bors try @rust-timer queue

add FCW to invalid `#[should_panic]` and `#[ignore]`

rust-bors · 2026-01-08T16:00:24Z

☀️ Try build successful (CI)
Build commit: cb3537c (cb3537c51779b496b81be46d14459b1e56e59c21, parent: bca37a20bd376ce3fd138e7cdee7fe704e0f8814)

rust-timer · 2026-01-08T16:42:04Z

Finished benchmarking commit (cb3537c): comparison URL.

Overall result: no relevant changes - no action needed

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.

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

Instruction count

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

Max RSS (memory usage)

Results (primary 1.9%, secondary -2.4%)

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

	mean	range	count
Regressions ❌ (primary)	1.9%	[1.3%, 2.8%]	3
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-2.4%	[-5.1%, -0.9%]	6
All ❌✅ (primary)	1.9%	[1.3%, 2.8%]	3

Cycles

Results (secondary -2.1%)

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)	-2.1%	[-2.1%, -2.1%]	1
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 475.924s -> 474.267s (-0.35%)
Artifact size: 390.87 MiB -> 390.86 MiB (-0.00%)

JonathanBrouwer · 2026-01-08T18:44:17Z

...mir-opt/pre-codegen/drop_boxed_slice.generic_in_place.PreCodegen.after.64bit.panic-abort.mir

                        }
                    }
                    scope 18 (inlined <std::alloc::Global as Allocator>::deallocate) {
-                        let mut _9: *mut u8;


Why did these mir-opt tests change?

JonathanBrouwer · 2026-01-10T12:20:22Z

compiler/rustc_builtin_macros/src/test.rs

+    // Add a trace to the originating test function, so that we can
+    // check if attributes that have `#[test]` or `#[bench]` as a requirement
+    // actually are annotated with said attributes
+    item.attrs.push(cx.attr_word(sym::test_trace, cx.with_def_site_ctxt(attr_sp)));


The crater run in #150727 (comment) had a bunch of failures (such as https://crater-reports.s3.amazonaws.com/pr-150727/try%2366388cc165a6c4ac98c074dc9f0281ff23528c55/gh/0958436455sarayut.master/log.txt) because this creates an attribute without a TokenStream. Can you look into this and make a regression test if easily possible?

JonathanBrouwer · 2026-01-10T12:47:03Z

@rustbot author

rust-bors · 2026-01-11T15:49:39Z

☔ The latest upstream changes (presumably #150957) made this pull request unmergeable. Please resolve the merge conflicts.

…h]` fn

rustbot · 2026-01-18T18:03:23Z

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.

rust-bors · 2026-01-18T21:44:21Z

☔ The latest upstream changes (presumably #151325) made this pull request unmergeable. Please resolve the merge conflicts.

JonathanBrouwer · 2026-01-19T19:05:44Z

Crater results of #150727 (comment)

Sadly quite a few real regressions.
A lot of regressions look like this, with various attribute macros:

#[test]
#[ignore]
#[serial_test::serial]
fn test_invalid_authentication() { ... }

Where the test macro rewrites the test function, which removes the trace attribute. This is quite unfortunate and I don't feel good about merging this, but I don't see a good way to fix this either. This can be fixed neither by the caller (because it does not control the macro) nor by the macro author (because it can't see the test trace attr, so it can't preserve it)

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 Dec 27, 2025

rustbot assigned jackh726 Dec 27, 2025

rustbot assigned JonathanBrouwer and unassigned jackh726 Dec 27, 2025