Normally, changes to rustfmt go into the separate repo. But, in
this case, the bug is introduced in a local change and therefore
isn't present in the rustfmt repo.
Rollup of 5 pull requests
Successful merges:
- rust-lang/rust#145468 (dedup recip, powi, to_degrees, and to_radians float tests)
- rust-lang/rust#145643 (coverage: Build an "expansion tree" and use it to unexpand raw spans)
- rust-lang/rust#145754 (fix(lexer): Don't require frontmatters to be escaped with indented fences)
- rust-lang/rust#146060 (fixup nix dev shell again)
- rust-lang/rust#146068 (compiletest: Capture panic messages via a custom panic hook)
r? `@ghost`
`@rustbot` modify labels: rollup
compiletest: Capture panic messages via a custom panic hook
Currently, output-capture of panic messages relies on special cooperation between `#![feature(internal_output_capture)]` and the default panic hook. That's a problem if we want to perform our own output capture, because the default panic hook won't know about our custom output-capture mechanism.
We can work around that by installing a custom panic hook that prints equivalent panic messages to a buffer instead.
The custom hook is always installed, but delegates to the default panic hook unless a panic-capture buffer has been installed on the current thread. A panic-capture buffer is only installed on compiletest test threads (by the executor), and only if output-capture is enabled.
---
Right now this PR doesn't provide any particular concrete benefits. But it will be essential as part of further efforts to replace compiletest's use of `#![feature(internal_output_capture)]` with our own output-capture mechanism.
r? jieyouxu
fix(lexer): Don't require frontmatters to be escaped with indented fences
The RFC only limits hyphens at the beginning of lines and not if they are indented or embedded in other content.
Sticking to that approach was confirmed by the T-lang liason at https://github.com/rust-lang/rust/issues/141367#issuecomment-3202217544
There is a regression in error message quality which I'm leaving for someone if they feel this needs improving.
Tracking issue: rust-lang/rust#136889Fixesrust-lang/rust#141367
coverage: Build an "expansion tree" and use it to unexpand raw spans
Historically and currently, coverage instrumentation assumes that all of a function's spans are in the same file and have the same syntax context. The spans extracted directly from MIR don't satisfy that assumption, so there is an “unexpansion” step that walks up each span's expansion-call-site tree to find a suitable span in the same context as the function's body span.
(That unexpansion step is what allows us to have somewhat reasonable coverage instrumentation for macros like `println!`, and for syntax like `for` and `?` that undergo desugaring expansion.)
The current unexpansion code mostly works fine in that “flat” single-file single-context world. But it's not suitable for incremental work towards proper expansion-aware coverage instrumentation, which would allow a function's coverage spans to encompass multiple expansion contexts and multiple files.
This PR therefore replaces the current unexpansion code with a more sophisticated system that uses the raw MIR spans to reconstruct an “expansion tree”, and then uses that tree to help perform most of the unexpansion work.
Building the tree is “overkill” for current unexpansion needs (though it does give some minor edge-case improvements), but my hope is that having the explicit tree available will be a big help when taking the next steps towards proper expansion-region support.
dedup recip, powi, to_degrees, and to_radians float tests
Deduplicates recip, powi, to_degrees, and to_radians float tests.
I had to fiddle and slightly increase the tolerances for a few comparisons, so maybe not all of the tests are worth deduplicating.
Part of rust-lang/rust#141726.
Best reviewed commit-by-commit.
r? `@tgross35`
Suggest method name with maybe ty mismatch
Fixesrust-lang/rust#146008
I think it's ok to suggest method name even when the return ty mismatch, since we only reporting in `Applicability::MaybeIncorrect`, user may add `()` and continue to fix following errors.
r? ```@estebank```
Detect negative literal inferred to unsigned integer
```
error[E0277]: the trait bound `usize: Neg` is not satisfied
--> $DIR/negative-literal-infered-to-unsigned.rs:2:14
|
LL | for x in -5..5 {
| ^^ the trait `Neg` is not implemented for `usize`
|
help: consider specifying an integer type that can be negative
|
LL | for x in -5isize..5 {
| +++++
```
Applying this suggestion will always end up in another E0308 error at the point where the unsigned inference comes from, which should help with understanding what the actual problem is.
Fixrust-lang/rust#83413.
resolve: Refactor `struct ExternPreludeEntry`
Avoid impossible combinations of fields and apply the first part of https://github.com/rust-lang/rust/pull/144737 (do not resolve erroneous entries repeatedly, keep them as `PendingBinding::Ready(None)` instead).
Add `Bound::copied`
Tracking Issue: https://github.com/rust-lang/rust/issues/145966
Some questions:
- [x] Should I update the documentation for `cloned` to actual used a `Clone` type instead of an integer?
- [x] I removed the `must_use` since this is a cheap copy, does that make sense?
Enforce in bootstrap that test must have stage at least 1 (except for compiletest)
This PR cleans up a bunch of test steps and adds metadata to them. I didn't yet touch the most complicated step (`CompileTest`), I'm leaving that for another PR.
Testing anything on stage 0 is only possible for compiletest and with `build.allow-compiletest-stage0`. Testing anything else on stage 0 will either produce a nice error or crash with a stage being subtracted below zero.
r? `@jieyouxu`
try-job: dist-x86_64-linux
try-job: aarch64-gnu
try-job: arm-android
try-job: `x86_64-gnu-llvm-20*`
try-job: `x86_64-msvc-*`
try-job: aarch64-apple
try-job: test-various
MIR dumping is a mess. There are lots of functions and entry points,
e.g. `dump_mir`, `dump_mir_with_options`, `dump_polonius_mir`,
`dump_mir_to_writer`. Also, it's crucial that `create_dump_file` is
never called without `dump_enabled` first being checked, but there is no
mechanism for ensuring this and it's hard to tell if it is satisfied on
all paths. (`dump_enabled` is checked twice on some paths, however!)
This commit introduces `MirWriter`, which controls the MIR writing, and
encapsulates the `extra_data` closure and `options`. Two existing
functions are now methods of this type. It sets reasonable defaults,
allowing the removal of many `|_, _| Ok(())` closures.
The commit also introduces `MirDumper`, which is layered on top of
`MirWriter`, and which manages the creation of the dump files,
encapsulating pass names, disambiguators, etc. Four existing functions
are now methods of this type.
- `MirDumper::new` will only succeed if dumps are enabled, and will
return `None` otherwise, which makes it impossible to dump when you
shouldn't.
- It also sets reasonable defaults for various things like
disambiguators, which means you no longer need to specify them in many
cases. When they do need to be specified, it's now done via setter
methods.
- It avoids some repetition. E.g. `dump_nll_mir` previously specifed the
pass name `"nll"` four times and the disambiguator `&0` three times;
now it specifies them just once, to put them in the `MirDumper`.
- For Polonius, the `extra_data` closure can now be specified earlier,
which avoids having to pass some arguments through some functions.
This commit exists purely to simplify reviewing: these functions will
become methods in the next commit. This commit indents them so that the
next commit is more readable.
The dynamic dispatch cost doesn't matter for MIR dumping, which is
perf-insensitive. And it's necessary for the next commit, which will
store some `extra_data` closures in a struct.
Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#144443 (Make target pointer width in target json an integer)
- rust-lang/rust#145174 (Ensure consistent drop for panicking drop in hint::select_unpredictable)
- rust-lang/rust#145592 (Fix format string grammar in docs and improve alignment error message for rust-lang/rust#144023)
- rust-lang/rust#145931 (Clarify that align_offset overaligns)
r? `@ghost`
`@rustbot` modify labels: rollup
Clarify that align_offset overaligns
The current documentation is not clear whether adding `a` to a pointer overaligns (align up) or underaligns (align down).
It should say this explicitly.
cc `@nagisa`
Fix format string grammar in docs and improve alignment error message for #144023
This PR improves error messages and documentation for format strings involving alignment and formatting traits.
Highlights:
- Clearer error messages for invalid alignment specifiers (e.g., `{0:#X>18}`), showing the expected `<`, `^`, or `>` and a working example:
println!("{0:>#18X}", value);
- Updated UI test `format-alignment-hash.rs` to reflect the improved error output.
- Documentation clarification: ensures examples correctly show how width, alignment, and traits like `x`, `X`, `#` combine.
Motivation:
Previously, using `#` with alignment and width produced confusing errors. This PR guides users on the correct syntax and provides actionable examples.
Testing:
- Built the compiler (`./x build`)
- Blessed and ran UI tests (`./x. test src/test/ui/fmt/format-alignment-hash.rs --bless`)
- Verified full test suite passes (`./x test`)
Issue: rust-lang/rust#144023
Ensure consistent drop for panicking drop in hint::select_unpredictable
There are a few alternatives to the implementation. The principal problem is that the selected value must be owned (in the sense of having a drop flag of sorts) when the unselected value is dropped, such that panic unwind goes through the drop of both. This ownership must then be passed on in return when the drop went smoothly.
The basic way of achieving this is by extracting the selected value first, at the cost of relying on the optimizer a little more for detecting the copy as constructing the return value despite having a place in the body. Unfortunately, that causes LLVM to discard the !unpredictable annotation (for some reason that is beyond my comprehension of LLVM).
<details>
<summary>Extract from the build log showing an unannotated select being used</summary>
```
2025-08-09T16:51:06.8790764Z 39: define noundef i64 `@test_int2(i1` noundef zeroext %p, i64 noundef %a, i64 noundef %b) unnamed_addr #0 personality ptr `@rust_eh_personality` {
2025-08-09T16:51:06.8791368Z check:47'0 X~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ error: no match found
2025-08-09T16:51:06.8791700Z 40: start:
2025-08-09T16:51:06.8791858Z check:47'0 ~~~~~~~
2025-08-09T16:51:06.8792043Z 41: %ret.i = select i1 %p, i64 %a, i64 %b
2025-08-09T16:51:06.8792293Z check:47'0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2025-08-09T16:51:06.8792686Z check:47'1 ? possible intended match
2025-08-09T16:51:06.8792946Z 42: ret i64 %ret.i
2025-08-09T16:51:06.8793127Z check:47'0 ~~~~~~~~~~~~~~~~
```
</details>
So instead, this PR includes a guard to drop the selected `MaybeUnit<T>` which is active only for the section where the unselected value is dropped. That leaves the code for selecting the result intact leading to the expected ir. That complicates the 'unselection' process a little bit since we require _both_ values as a result of that intrinsic call. Since the arguments alias, this portion as well as the drop guard uses raw pointers.
Closes: rust-lang/rust#145148
Prior: rust-lang/rust#139977
Use absolute path to llvm-bolt, merge-fdata rather than PATH
This unconditionally uses the provided LLVM toolchain's BOLT. I'm not sure that makes sense, but since we don't build BOLT as part of Rust's build of LLVM today, it's probably the right option for now.
This avoids breaking the build on not being able to find the llvm-bolt executable.
Detect missing `if let` or `let-else`
During `let` binding parse error and encountering a block, detect if there is a likely missing `if` or `else`:
```
error: expected one of `.`, `;`, `?`, `else`, or an operator, found `{`
--> $DIR/missing-if-let-or-let-else.rs:14:25
|
LL | let Some(x) = foo() {
| ^ expected one of `.`, `;`, `?`, `else`, or an operator
|
help: you might have meant to use `if let`
|
LL | if let Some(x) = foo() {
| ++
help: alternatively, you might have meant to use `let else`
|
LL | let Some(x) = foo() else {
| ++++
```
Fixrust-lang/rust#107806.
Update `browser-ui-test` version to `0.21.3`
I cannot test it locally because of this bug:
```
error: couldn't generate documentation: failed to read column from disk: data consumer error: missing field `unknown number` at line 1 column 8
|
= note: failed to create or modify "build/x86_64-unknown-linux-gnu/test/rustdoc-gui/doc/search.index/entry/": failed to read column from disk: data consumer error: missing field `unknown number` at line 1 column 8
```
So I'll iterate through CI checks I guess.
r? ghost
Fix `sys::process::windows::tests::test_thread_handle` spurious failure
Instead of sleeping, wait for the process to finish so that we can be sure it's done. We use a timeout because otherwise this test can be stuck indefinitely if it fails (unfortunately std doesn't currently have a way to wait with a timeout so a manual OS API call is necessary).
I also changed the test to run `whoami` and pipe the output to null so that it doesn't clutter up the test output.
Fixesrust-lang/rust#146024
```
error[E0277]: the trait bound `usize: Neg` is not satisfied
--> $DIR/negative-literal-infered-to-unsigned.rs:2:14
|
LL | for x in -5..5 {
| ^^ the trait `Neg` is not implemented for `usize`
|
help: consider specifying an integer type that can be negative
|
LL | for x in -5isize..5 {
| +++++
```
This unconditionally uses the provided LLVM toolchain's BOLT. I'm not
sure that makes sense, but since we don't build BOLT as part of Rust's
build of LLVM today, it's probably the right option for now.
This avoids breaking the build on not being able to find the llvm-bolt
executable.
With a patch applied to count the number of unifications,
and running the query `Option<T>, (T -> U) -> Option<U>`
before: performed unifyFunctionType on 17484 functions
after: performed unifyFunctionType on 3055 functions