The panic_abort crate must be compiled with panic=abort, but cargo
doesn't allow setting the panic strategy for a single crate the usual
way using panic="abort", but luckily per-package rustflags do allow
this. Bootstrap previously handled this in its rustc wrapper, but for
example the build systems of cg_clif and cg_gcc don't use the rustc
wrapper, so they would either need to add one, patch the standard
library or be unable to build a sysroot suitable for both panic=abort
and panic=unwind (as is currently the case).
~~I've added a `min_divisor` configuration option, default to 4, to not
trigger on smaller divisibility operations. I would prefer not to lint
`if a & 1 == 0` as `if a.is_multiple_of(2)` by default because the
former is very idiomatic in systems (and embedded) programming.~~
~~A `min_and_mask_size` option, defaulting to 3, sets the default bits
to be and-masked before this lint triggers; that would be `n` in `v &
((1 << n) - 1) == 0`. The form `v % 10 == 0` is always linted.~~
~~This PR will stay in draft mode until the next rustup which will mark
`unsigned_is_multiple_of` stable for Rust 1.87.0, and the feature flags
will be removed.~~
What should its category be? I've used "complexity", but "pedantic"
might be suitable as well.
Closerust-lang/rust-clippy#14289
changelog: [`manual_is_multiple_of`]: new lint
r? ghost
Update books
## rust-lang/book
1 commits in 4433c9f0cad8460bee05ede040587f8a1fa3f1de..8a6d44e45b7b564eeb6bae30507e1fbac439d72d
2025-06-18 17:06:36 UTC to 2025-06-18 17:06:36 UTC
- Chapter 12 from tech review (rust-lang/book#4410)
## rust-lang/reference
6 commits in d4c66b346f4b72d29e70390a3fa3ea7d4e064db1..50fc1628f36563958399123829c73755fa7a8421
2025-06-19 02:02:39 UTC to 2025-06-17 21:18:46 UTC
- Document inferred const args (`feature(generic_arg_infer)`) (rust-lang/reference#1835)
- const_eval: we allow references to statics and promoteds (rust-lang/reference#1858)
- Fix missing rule on destructors (rust-lang/reference#1861)
- Fix inconsistent heading depth (rust-lang/reference#1860)
- Fix recursive root-accessible grammar check (rust-lang/reference#1852)
- Fix grammar links (rust-lang/reference#1851)
## rust-lang/rust-by-example
1 commits in 9baa9e863116cb9524a177d5a5c475baac18928a..05c7d8bae65f23a1837430c5a19be129d414f5ec
2025-06-18 13:15:17 UTC to 2025-06-18 13:15:17 UTC
- Revert "introduce new ````@media```` query to set a higher content width on ultra wide screens" (rust-lang/rust-by-example#1939)
Reduce uses of `hir_crate`.
I tried rebasing my old incremental-HIR branch. This is a by-product, which is required if we want to get rid of `hir_crate` entirely.
The second commit is a drive-by cleanup. It can be pulled into its own PR.
r? ````@oli-obk````
Implement send_signal for unix child processes
Tracking issue: rust-lang/rust#141975
There are two main differences between my implementation and the Public API section of the tracking issue. ~First, `send_signal` requires a mutable reference, like `Child::kill`.~ Second, `ChildExt` has `Sealed` as a supertrait, bringing it more in line with other extension traits like `CommandExt`.
try-job: `dist-various*`
try-job: `test-various*`
Extract some shared code from codegen backend target feature handling
There's a bunch of code duplication between the GCC and LLVM backends in target feature handling. This moves that into new shared helper functions in `rustc_codegen_ssa`.
The first two commits should be purely refactoring. I am fairly sure the LLVM-side behavior stays the same; if the GCC side deliberately diverges from this then I may have missed that. I did account for one divergence, which I do not know is deliberate or not: GCC does not seem to use the `-Ctarget-feature` flag to populate `cfg(target_feature)`. That seems odd, since the `-Ctarget-feature` flag is used to populate the return value of `global_gcc_features` which controls the target features actually used by GCC. ``@GuillaumeGomez`` ``@antoyo`` is there a reason `target_config` ignores `-Ctarget-feature` but `global_gcc_features` does not? The second commit also cleans up a bunch of unneeded complexity added in https://github.com/rust-lang/rust/pull/135927.
The third commit extracts some shared logic out of the functions that populate `cfg(target_feature)` and the backend target feature set, respectively. This one actually has some slight functional changes:
- Before, with `-Ctarget-feature=-feat`, if there is some other feature `x` that implies `feat` we would *not* add `-x` to the backend target feature set. Now, we do. This fixesrust-lang/rust#134792.
- The logic that removes `x` from `cfg(target_feature)` in this case also changed a bit, avoiding a large number of calls to the (uncached) `sess.target.implied_target_features` (if there were a large number of positive features listed before a negative feature) but instead constructing a full inverse implication map when encountering the first negative feature. Ideally this would be done with queries but the backend target feature logic runs before `tcx` so we can't use that...
- Previously, if feature "a" implied "b" and "b" was unstable, then using `-Ctarget-feature=+a` would also emit a warning about `b`. I had to remove this since when accounting for negative implications, this emits a ton of warnings in a bunch of existing tests... I assume this was unintentional anyway.
The fourth commit increases consistency of the GCC backend with the LLVM backend.
The last commit does some further cleanup:
- Get rid of RUSTC_SPECIAL_FEATURES. It was only needed for s390x "backchain", but since LLVM 19 that is always a regular target feature so we don't need this hack any more. The hack also has various unintended side-effects so we don't want to keep it. Fixes https://github.com/rust-lang/rust/issues/142412.
- Move RUSTC_SPECIFIC_FEATURES handling into the shared parse_rust_feature_flag helper so all consumers of `-Ctarget-feature` that only care about actual target features (and not "crt-static") have it. Previously, we actually set `cfg(target_feature = "crt-static")` twice: once in the backend target feature logic, and once specifically for that one feature. IIUC, some targets are meant to ignore `-Ctarget-feature=+crt-static`, it seems like before this PR that flag still incorrectly enabled `cfg(target_feature = "crt-static")` (but I didn't test this).
- Move fixed_x18 handling together with retpoline handling.
- Forbid setting fixed_x18 as a regular target feature, even unstably. It must be set via the `-Z` flag.
``@bjorn3`` I did not touch the cranelift backend here, since AFAIK it doesn't really support target features. But if you ever do, please use the new helpers. :)
Cc ``@workingjubilee``
rewrite `optimize` attribute to use new attribute parsing infrastructure
r? ```@oli-obk```
I'm afraid we'll get quite a few of these PRs in the future. If we get a lot of trivial changes I'll start merging multiple into one PR. They should be easy to review :)
Waiting on #138165 first
Use jemalloc for Clippy
The tool macros are annoying, we should IMO just get rid of them, create separate steps for each tool and (re)use some builders in them to share the build code.
r? `@ghost`
Use jemalloc for Clippy
The tool macros are annoying, we should IMO just get rid of them, create separate steps for each tool and (re)use some builders in them to share the build code.
r? `@ghost`
For things that only change the valid ranges, we can just skip the `LLVMBuildBitCast` call.
I tried to tweak this a bit more and broke stuff, so I also added some extra tests for that as we apparently didn't have coverage.
- `Ident::from_str_and_span` -> `Ident::new` when the string is
pre-interned.
- `Ident::from_str` -> `Ident::with_dummy_span` when the string is
pre-interned.
- `_d` and `_e` are unused.
- `Ident::from_str_and_span` -> `Ident::new` when the string is
pre-interned.
- `Ident::from_str` -> `Ident::with_dummy_span` when the string is
pre-interned.
- `_d` and `_e` are unused.
`{{root}}` is supposed to be an internal-only name but it shows up in
the output.
(I'm working towards a more general fix -- a universal "joiner" function
that can be used all over the place -- but I'm not there yet, so let's
fix this one in-place for now.)
Use a distinct `ToString` implementation for `u128` and `i128`
Part of https://github.com/rust-lang/rust/issues/135543.
Follow-up of rust-lang/rust#136264.
When working on https://github.com/rust-lang/rust/pull/142098, I realized that `i128` and `u128` could also benefit from a distinct `ToString` implementation so here it.
The last commit is just me realizing that I forgot to add the format tests for `usize` and `isize`.
Here is the bench comparison:
| bench name | last nightly | with this PR | diff |
|-|-|-|-|
| bench_i128 | 29.25 ns/iter (+/- 0.66) | 17.52 ns/iter (+/- 0.7) | -40.1% |
| bench_u128 | 34.06 ns/iter (+/- 0.21) | 16.1 ns/iter (+/- 0.6) | -52.7% |
I used this code to test:
```rust
#![feature(test)]
extern crate test;
use test::{Bencher, black_box};
#[inline(always)]
fn convert_to_string<T: ToString>(n: T) -> String {
n.to_string()
}
macro_rules! decl_benches {
($($name:ident: $ty:ident,)+) => {
$(
#[bench]
fn $name(c: &mut Bencher) {
c.iter(|| convert_to_string(black_box({ let nb: $ty = 20; nb })));
}
)+
}
}
decl_benches! {
bench_u128: u128,
bench_i128: i128,
}
```
