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
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`
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?
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
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
Hard-code `char::is_control`
Split off from https://github.com/rust-lang/rust/pull/145219
According to
https://www.unicode.org/policies/stability_policy.html#Property_Value, the set of codepoints in `Cc` will never change. So we can hard-code the patterns to match against instead of using a table.
This doesn't change the generated assembly, since the lookup table is small enough that[ LLVM is able to inline the whole search](https://godbolt.org/z/bG8dM37YG). But this does reduce the chance of regressions if LLVM's heuristics change in the future, and means less generated Rust code checked in to `unicode-data.rs`.
Previously, attempting to create/truncate a file without write/append access
would result in platform-specific error messages:
- Unix: "Invalid argument"
- Windows: raw OS error code 87
These error codes look like system errors, which could waste hours
of debugging for what is actually an API misuse issue.
Instead of a tuple, select the dropped value and its guard with two
separate calls to the intrinsic which makes both calls have a
pointer-valued argument that should be simpler in codegen. Use the same
condition on all (not an inverted condition) to clarify the intent of
parallel selection. This should also be a simpler value-dependency chain
if the guard is deduced unused (i.e. drop_in_place a noop for the type).
Optimize `.ilog({2,10})` to `.ilog{2,10}()`
Optimize `.ilog({2,10})` to `.ilog{2,10}()`
Inform compiler of optimizations when the base is known at compile time and there's a cheaper method available:
* `{integer}.checked_ilog(2)` -> `{integer}.checked_ilog2()`
* `{integer}.checked_ilog(10)` -> `{integer}.checked_ilog10()`
* `{integer}.ilog(2)` -> `{integer}.ilog2()`
* `{integer}.ilog(10)` -> `{integer}.ilog10()`
Implementation: `#[feature(nonpoison_condvar)]`
Tracking Issue: https://github.com/rust-lang/rust/issues/134645
This PR continues the effort made in https://github.com/rust-lang/rust/pull/144022 by adding the implementation of `nonpoison::condvar`.
Many of the changes here are similar to the changes made to implement `nonpoison::mutex`.
There are two other changes here. The first is that the `Barrier` implementation is migrated to use the `nonpoison::Condvar` instead of the `poison` variant. The second (which might be subject to some discussion) is that `WaitTimeoutResult` is moved up to `mod.rs`, as both `condvar` variants need that type (and I do not know if there is a better place to put it now).
### Related PRs
- `nonpoison_rwlock` implementation: https://github.com/rust-lang/rust/pull/144648
- `nonpoison_once` implementation: https://github.com/rust-lang/rust/pull/144653
fix(lib-std-fs): handle `usize` overflow in `read*`
I assume this is a non-breaking change, as there would be an OOM `panic` anyways. This patch ensures a fast-fail when there's not enough memory to load the file. This only changes behavior on platforms where `usize` is smaller than 64bits
Inform compiler of optimizations when the base is known at compile time
and there's a cheaper method available:
* `{integer}.checked_ilog(2)` -> `{integer}.checked_ilog2()`
* `{integer}.checked_ilog(10)` -> `{integer}.checked_ilog10()`
* `{integer}.ilog(2)` -> `{integer}.ilog2()`
* `{integer}.ilog(10)` -> `{integer}.ilog10()`
fix(std): Fix undefined reference to __my_thread_exit on QNX 8.0
When cross-compiling for the x86_64/aarch64-unknown-nto-qnx800 target (QNX SDP 8.0), the build fails during the final link stage with the error:
```
error: linking with `qcc` failed: exit status: 1
...
= note: undefined reference to `__my_thread_exit'
```
- **On QNX 7.1**: The __my_thread_exit symbol is defined and exported by the main C library (libc.a/libc.so). The std backtrace code can therefore successfully take its address at compile time.
- **On QNX 8.0**: As part of a toolchain modernization, this symbol has been refactored. It is no longer present in any of the standard system libraries (.a or .so).
This patch addresses the problem at its source by conditionally compiling the problematic code.
Fixesrust-lang/rust#142726
The current documentation is not clear whether adding `a` to a pointer overaligns (align up) or underaligns (align down).
It should say this explicitly.
`const`ify (the unstable) `str::as_str`
Tracking issue: rust-lang/rust#130366
The method was not initially marked `const` presumably because it is only useful with `Deref`. But now that const traits seem to be a thing that can actually become real, why not make it `const`?
PR `const`ifying `Deref`: rust-lang/rust#145279