Derives `Copy` for `ffi::FromBytesUntilNulError`
[`ffi::FromBytesWithNulError` derives `Copy` since Rust 1.93](https://github.com/rust-lang/rust/commit/2f5a3d4b06a0a9e8749c2e361758ec517df0c96a) while `ffi::FromBytesUntilNulError` doesn't.
This Pr fixes that by deriving `Copy` for `ffi::FromBytesUntilNulError`.
I encountered this issue while I was working in a const context.
Note: I couldn't find any documentation about what kind of PR is allowed. As this one is very small, I guess it is ok to submit it directly without opening an issue first?
Remove `UncheckedIterator`
The only remaining usage of `UncheckedIterator` was in `array::{try_,}from_trusted_iterator`. So, replace `array::repeat` and array's `Clone` impl with a manual `from_fn` call rather than going through unnecessary abstractions, and remove the `UncheckedIterator` trait.
Implement `OsStr::split_at`
See rust-lang/rust#156199
This allows splitting only on valid UTF-8 boundaries, regardless of the platform, which avoids cross-platform landmines.
change `other uses of const` to `raw pointers` in const keyword docs
this section only talks about how `const` is used in raw pointers and doesn't give any other uses, so in my opinion it would be a bit clearer if the section was named `raw pointers` or something similar.
Fix typo in `format_into` docs: signed -> unsigned
The documentation for the `format_into` methods on unsigned integers
still said "in signed decimal format". Change them to say "unsigned".
Change division to multiplication in floating-point midpoint
Multiplication is faster than division on most (all?) platforms. While the optimizer will handle this, there is really no point in relying on that. Using multiplication directly will not have any drawbacks and are numerically identical (in this case since 1.0 / 2.0 == 0.5)
Consider the examples at https://godbolt.org/z/oMvb9vobG where it is clear that the non-optimized version uses division, while the optimized version uses multiplication.
library: Fix std compilation for espidf target in unix::process
Fixes a regression on the riscv32imac-esp-espidf target caused by commit 7bf5fe7bf8 (linked issue rust-lang/rust#156537) . The unix_kill_process_group feature attempts to use libc::SIGKILL, which is not supported on the espidf target.
Discussed in `esp-idf-sys` issue: https://github.com/esp-rs/esp-idf-sys/issues/419
remove/update various cfg(miri)
I went over all `cfg(miri)` in `library/`. Most of the things I noticed have become separate PRs; these here are the few remaining scattered little fixes in various places.
This is the only remaining place that uses `UncheckedIterator`. So,
replace `array::repeat` and array's `Clone` impl with a manual `from_fn`
call rather than going through unnecessary abstractions.
Removal of `UncheckedIterator` will be done in a later commit.
actually run the temp_dir doctest
No idea why this currently doesn't get run.
That said, this might fail in Miri, so we may have to wait for https://github.com/rust-lang/miri/pull/5029.
Move `std::io::util` to `core::io`
ACP: https://github.com/rust-lang/libs-team/issues/755
Tracking issue: https://github.com/rust-lang/rust/issues/154046
Subset of: https://github.com/rust-lang/rust/pull/154684
## Description
Moves utility types and functions from `std::io::util` and `std::io` to `core::io`, leaving any IO trait implementations behind. They will be moved along with the traits themselves. Certain documentation links had to be amended.
- `Chain`
- `Empty`
- `Repeat`
- `Sink`
- `Take`
- `empty`
- `repeat`
- `sink`
---
## Notes
* This can be reviewed independently of the other PRs tracked in rust-lang/rust#154046.
* `Chain` and `Take` were previously in the main `mod.rs` file for `std::io`, but I've chosen to move them into the `util.rs` file in `core::io` instead. I think they make more sense in that file, but I'm happy to move them into `mod.rs` if that's a controversial decision.
* No AI tooling of any kind was used during the creation of this PR.
Move `std::io::Cursor` to `core::io`
ACP: https://github.com/rust-lang/libs-team/issues/755
Tracking issue: https://github.com/rust-lang/rust/issues/154046
Subset of: https://github.com/rust-lang/rust/pull/154684
## Description
Moves `std::io::Cursor` to `core::io`, leaving the IO trait implementations behind. They will be moved along with the traits themselves. Certain documentation links had to be amended, and a private/unstable `into_parts_mut` method was added to allow the internals to remain private.
---
## Notes
* This can be reviewed independently of the other PRs tracked in rust-lang/rust#154046.
* No AI tooling of any kind was used during the creation of this PR.
Jonathan Brouwer