rust/library/core/src, branch master

Rollup merge of #147204 - camsteffen:array-windows-ref, r=joboet

2025-10-01T16:42:36+00:00

Refactor ArrayWindows to use a slice [Tracking issue](https://github.com/rust-lang/rust/issues/75027)

Change ArrayWindows to use a slice

2025-10-01T13:03:19+00:00

Rollup merge of #146979 - npmccallum:nanosecs, r=Mark-Simulacrum

2025-09-29T01:56:42+00:00

constify Default on Nanoseconds

Rollup merge of #146675 - Jules-Bertholet:sync-nonexclusive, r=Mark-Simulacrum

2025-09-28T16:13:12+00:00

Allow shared access to `Exclusive` when `T: Sync` Addresses libs-api request in https://github.com/rust-lang/rust/issues/98407#issuecomment-3299348713. Adds the following trait impls to `Exclusive`, all bounded on `T: Sync`: - `AsRef` - `Clone` - `Copy` - `PartialEq` - `StructuralPartialEq` - `Eq` - `Hash` - `PartialOrd` - `Ord` - `Fn` ``@rustbot`` label T-libs-api

Rollup merge of #147095 - fmease:libprivrepr, r=dtolnay

2025-09-28T07:15:29+00:00

Library: Remove remaining private `#[repr]` workarounds With https://github.com/rust-lang/rust/pull/116882 finally merged, gating these `repr`s behind cfg `not(doc)` is no longer necessary to achieve a private repr. Follow up to https://github.com/rust-lang/rust/pull/128046 (that was enabled via https://github.com/rust-lang/rust/pull/115439). With that, https://github.com/rust-lang/rust/pull/116743 is now fully realized at long last. cc ``@dtolnay``

Rollup merge of #147082 - danielverkamp:fmt-alternate-octal-binary-mixup, r=Noratrieb

2025-09-28T07:15:27+00:00

formatting_options: fix alternate docs 0b/0o mixup The descriptions of the alternate forms of Octal and Binary were swapped in the doc comment for FormattingOptions::alternate().

Rollup merge of #147076 - joshuarayton:more-float-constants-issue, r=tgross35

2025-09-27T19:26:00+00:00

update issue number for more_float_constants Update issue number from https://github.com/rust-lang/rust/issues/103883 to https://github.com/rust-lang/rust/issues/146939 r? ``@tgross35``

Rollup merge of #146037 - aapoalas:reborrow-lang-experiment, r=tmandry

2025-09-27T19:25:56+00:00

Introduce CoerceShared lang item and trait, and basic Reborrow tests Part of rust-lang/rust#145612: This introduces the `CoerceShared` trait which is the `Reborrow` equivalent of a `&mut T` -> `&T` coercion. The trait has a `Target` GAT which makes this (currently) unique in the `core/src/marker.rs`; I'm not sure if this can be considered problematic. Maybe this is not the way such things should be done at the marker trait level? Or maybe it is fine. Improtantly, this PR introduces a battery of basic `Reborrow` and `CoerceShared` tests. These test the very basics of the feature; custom marker types intended to have exclusive semantics (`Custom<'a>(PhantomData<&'a mut ()>)`), custom exclusive reference wrappers, and standard library exclusive reference wrappers (`Pin<&mut T>` and `Option<&mut T>`). None of these of course work since the implementation for `Reborrow` and `CoerceShared` is entirely missing, but this is the first step towards making these work. Future PRs will introduce more tests, such as "recursive" reborrowing (ie. reborrowing structs that contain multiple reborrowable fields) and checks around the lifetime semantics of reborrowing ie. that a reborrow produces a new type with the same lifetime as the original.

Library: Remove remaining private `#[repr]` workarounds

2025-09-27T15:09:01+00:00

Co-authored-by: David Tolnay

Remove `cfg(bootstrap)` for `doc_cfg` feature following #141925

2025-09-27T09:29:49+00:00