Fix typo in ManuallyDrop's documentation
```diff
- /// A wrapper to inhibit compiler from automatically calling `T`’s destructor.
+ /// A wrapper to inhibit the compiler from automatically calling `T`’s destructor.
```
from_str_radix: outline only the panic function
In the `{integer}::from_str_radix` function, the radix check is labeled as `cold` and `inline(never)`, along with its corresponding panic. It probably was intended to apply these attributes only to the panic function.
Display walltime benchmarks with subnanosecond precision
With modern CPUs running at more than one cycle per nanosecond the current precision is insufficient to resolve differences worth several cycles per iteration.
Granted, walltime benchmarks often are noisy but occasionally, especially when no allocations are involved, the difference really is just a few cycles.
example results when benchmarking 1-4 serialized ADD instructions and an empty bench body
```
running 4 tests
test add ... bench: 0.24 ns/iter (+/- 0.00)
test add2 ... bench: 0.48 ns/iter (+/- 0.01)
test add3 ... bench: 0.72 ns/iter (+/- 0.01)
test add4 ... bench: 0.96 ns/iter (+/- 0.01)
test empty ... bench: 0.24 ns/iter (+/- 0.00)
```
Add benchmarks for `impl Debug for str`
In order to inform future perf improvements and prevent regressions, lets add some benchmarks that stress `impl Debug for str`.
---
As I am currently working on improving the perf in https://github.com/rust-lang/rust/pull/121150, its nice to have these benchmarks.
Writing them, I also saw that escapes are written out one char at a time, even though other parts of the code are already optimizing that via `as_str`, which I intend to do as well as a followup improvement.
r? ``@cuviper``
☝🏻 as you were also assigned to https://github.com/rust-lang/rust/pull/121150, CC ``@the8472`` if you want to steal the review :-)
fix#124714 str.to_lowercase sigma handling
Hello,
This PR fixes issue #124714 about 'Σ' handling in `str.to_lowercase()`.
The fix consists in considering the full original string during 'Σ' handling instead of considering just the substring left after the optimized ascii handling.
A new test is added to avoid regression.
Thanks!
Implement `as_chunks` with `split_at_unchecked`
We were discussing various ways to do [this on Discord](https://discord.com/channels/273534239310479360/273541522815713281/1236946363120619521), and in the process I noticed that <https://rust.godbolt.org/z/1P16P37Go> is emitting a panic path inside `as_chunks`. It optimizes out in release, but we could just not do that in the first place.
We're already doing unsafe code that depends on this value being calculated correctly, so might as well call `split_at_unchecked` instead of `split_at`.
Rollup of 8 pull requests
Successful merges:
- #123344 (Remove braces when fixing a nested use tree into a single item)
- #124587 (Generic `NonZero` post-stabilization changes.)
- #124775 (crashes: add lastest batch of crash tests)
- #124869 (Make sure we don't deny macro vars w keyword names)
- #124876 (Simplify `use crate::rustc_foo::bar` occurrences.)
- #124892 (Update cc crate to v1.0.97)
- #124903 (Ignore empty RUSTC_WRAPPER in bootstrap)
- #124909 (Reapply the part of #124548 that bors forgot)
r? `@ghost`
`@rustbot` modify labels: rollup
Avoid a cast in `ptr::slice_from_raw_parts(_mut)`
Casting to `*const ()` or `*mut ()` is no longer needed after https://github.com/rust-lang/rust/pull/123840 so let's make the MIR smaller (and more inline-able, as seen in the tests).
If [ACP#362](https://github.com/rust-lang/libs-team/issues/362) goes through we can keep calling `ptr::from_raw_parts(_mut)` in these also without the cast, but that hasn't had any libs-api attention yet, so I'm not waiting on it.
Convert instances of `target_os = "macos"` to `target_vendor = "apple"`
https://github.com/rust-lang/rust/pull/124491 migrated towards using `target_vendor = "apple"` more, as there's very little difference between iOS, tvOS, watchOS and visionOS. In that PR, I only did the changes where the standard library already had fixes for iOS, that I could confidently apply to the other targets.
However, there's actually also not that big of a gap between macOS and the aforementioned platforms - so in this PR, I've gone through a few of the instances of `target_os = "macos"` and replaced it with `target_vendor = "apple"` to improve support on those platforms, see the commits for details.
r? workingjubilee
CC `@thomcc` `@simlay` (do tell me if I should stop pinging you on these Apple PRs)
`@rustbot` label O-apple
Correct the const stabilization of `last_chunk` for slices
`<[T]>::last_chunk` should have become const stable as part of <https://github.com/rust-lang/rust/pull/117561>. Update the const stability gate to reflect this.
Rollup of 4 pull requests
Successful merges:
- #124520 (Document that `create_dir_all` calls `mkdir`/`CreateDirW` multiple times)
- #124724 (Prefer lower vtable candidates in select in new solver)
- #124771 (Don't consider candidates with no failing where clauses when refining obligation causes in new solver)
- #124808 (Use `super_fold` in `RegionsToStatic` visitor)
r? `@ghost`
`@rustbot` modify labels: rollup
Add constants for f16 and f128
- Commit 1 adds associated constants for `f16`, excluding NaN and infinities as these are implemented using arithmetic for `f32` and `f64`.
- Commit 2 adds associated constants for `f128`, excluding NaN and infinities.
- Commit 3 adds constants in `std::f16::consts`.
- Commit 4 adds constants in `std::f128::consts`.
Casting to `*const ()` or `*mut ()` just bloats the MIR, so let's not.
If ACP#362 goes through we can keep calling `ptr::from_raw_parts(_mut)` in these also without the cast, but that hasn't had any libs-api attention yet, so I'm not waiting on it.
This uses `libc::fcntl`, which, while not explicitly marked as available
in the headers, is already used by `File::sync_all` and `File::sync_data`
on these platforms, so should be fine to use here as well.
Tested in the iOS simulator with something like:
```
let mut buf = vec![0; c_int::MAX as usize - 1 + 2];
let read_bytes = f.read(&mut buf).unwrap();
```
Document That `f16` And `f128` Hardware Support is Limited (v2)
This PR is identical to #123892, which was approved and merged but then removed from master by a force-push due to a [CI bug](https://rust-lang.zulipchat.com/#narrow/stream/242791-t-infra/topic/ci.20broken.3F).
r? ghost
Original PR description:
---
This adds a small paragraph to the recently added f16 and f128 types explaining that hardware support may be limited, and that performance may suffer as a result of that.
I mainly wrote this because I felt it may be useful to express in some form; as a launchpoint for readers of the documentation if they have issues with performance.
I tried to word the documentation in a way that doesn't create false assumptions (that f16/f128 is too slow to use, for instance), removing the software implementation part could mislead people to thinking that f16/f128 is only available on some platforms, not all, so I believe it is important to keep in.\
"not all *major* platforms" is specifically said so as to not be redundant, because not all platforms implement many things, but the average rustacean is probably going to be using x86_64 or aarch64 derived ISA's, which is who this documentation is targeted towards.
I'm not sure of the best way to word the documentation, or if it should even be added, but I feel like it may be useful to have (potentially in a reworded way, I'm not very confident in the current wording and cannot decide if that is because it is too vague to be useful or too specific to be generally correct).
The code is written in a way to support 32-bit iOS and tvOS ARM devices,
for future compatibility even though we currently only have a target for
32-bit iOS ARM.
Co-authored-by: Jubilee <46493976+workingjubilee@users.noreply.github.com>
Update library/core/src/primitive_docs.rs
Remove orphaned doc link and clean up grammar a bit
Update library/core/src/primitive_docs.rs
Co-authored-by: Jubilee <46493976+workingjubilee@users.noreply.github.com>
Update library/core/src/primitive_docs.rs
Rewrite f16 and f128 hw support comments to match PR feedback
I wrote RISC-V allcaps in all cases, and wrote amd64 lowercase in all
cases, im not sure if either is the more correct way for either
platform, thats just how I normally write them, if theres a precedent
elsewhere it should probably be changed to match though.
Update library/core/src/primitive_docs.rs
Co-authored-by: Jubilee <46493976+workingjubilee@users.noreply.github.com>
Update library/core/src/primitive_docs.rs
Co-authored-by: Jubilee <46493976+workingjubilee@users.noreply.github.com>
Update library/core/src/primitive_docs.rs
library/std: Fix build for NetBSD targets with 32-bit `c_long`
This fixes building `std` for targets like `mipsel-unknown-netbsd`.
If `c_long` is an `i64`, this conversion works with `Into`. But if it's an `i32`, this failed to convert a `u32` to an `i32`.
This fixes building `std` for targets like `mipsel-unknown-netbsd`.
If `c_long` is an `i64`, this conversion works with `Into`. But if it's
an `i32`, this failed to convert a `u32` to an `i32`.
