Little improves in CString `new` when creating from slice
Old code already contain optimization for cases with `&str` and `&[u8]` args. This commit adds a specialization for `&mut[u8]` too.
Also, I added usage of old slice in search for zero bytes instead of new buffer because it produce better code for constant inputs on Windows LTO builds. For other platforms, this wouldn't cause any difference because it calls `libc` anyway.
Inlined `_new` method into spec trait to reduce amount of code generated to `CString::new` callers.
doc: guarantee call order for sort_by_cached_key
`slice::sort_by_cached_key` takes a caching function `f: impl FnMut(&T) -> K`, which means that the order that calls to the caching function are made is user-visible. This adds a clause to the documentation to promise the current behavior, which is that `f` is called on all elements of the slice from left to right, unless the slice has len < 2 in which case `f` is not called.
For example, this can be used to ensure that the following code is a correct way to involve the index of the element in the sort key:
```rust
let mut index = 0;
slice.sort_by_cached_key(|x| (my_key(index, x), index += 1).0);
```
Fix stdarch submodule pointing to commit outside tree
PR #93016 was merged with the stdarch submodule pointing to a commit in
a PR branch and not in master. This was due to a circular dependency
between the rust and stdarch changes which would cause the other to fail
to build.
cc #75109
PR #93016 was merged with the stdarch submodule pointing to a commit in
a PR branch and not in master. This was due to a circular dependency
between the rust and stdarch changes which would cause the other to fail
to build.
cc #75109
add `rustc_diagnostic_item` attribute to `AtomicBool` type
I wanted to use this in clippy and found that it didn't work. So hopefully this addition will fix it.
Use `carrying_{mul|add}` in `num::bignum`
Now that we have (unstable) methods for this, we don't need the bespoke trait methods for it in the `bignum` implementation.
cc #85532
Add `log2` and `log10` to `NonZeroU*`
This version is nice in that it doesn't need to worry about zeros, and thus doesn't have any error cases.
cc `int_log` tracking issue #70887
(I didn't add them to `NonZeroI*` despite it being on `i*` since allowing negatives bring back the error cases again.)
Remove deprecated LLVM-style inline assembly
The `llvm_asm!` was deprecated back in #87590 1.56.0, with intention to remove
it once `asm!` was stabilized, which already happened in #91728 1.59.0. Now it
is time to remove `llvm_asm!` to avoid continued maintenance cost.
Closes#70173.
Closes#92794.
Closes#87612.
Closes#82065.
cc `@rust-lang/wg-inline-asm`
r? `@Amanieu`
fix const_ptr_offset_from tracking issue
The old tracking issue #41079 was for exposing those functions at all, and got closed when they were stabilized. We had nothing tracking their `const`ness so I opened a new tracking issue: https://github.com/rust-lang/rust/issues/92980.
Copy an example to PartialOrd as well
In https://github.com/rust-lang/rust/pull/88202 I added an example for deriving PartialOrd on enums, but only later did I realize that I actually put the example on Ord.
This copies the example to PartialOrd as well, which is where I intended for it to be.
We could also delete the example on Ord, but I see there's already some highly similar examples shared between Ord and PartialOrd, so I figured we could leave it.
I also changed some type annotations in an example from `x : T` to the more common style (in Rust) of `x: T`.
Clarify explicitly that BTree{Map,Set} are ordered.
One of the main reasons one would want to use a BTree{Map,Set} rather than a Hash{Map,Set} is because they maintain their keys in sorted order; but this was never explicitly stated in the top-level docs (it was only indirectly alluded to there, and stated explicitly in the docs for `iter`, `values`, etc.)
This PR states the ordering guarantee more prominently.
Add diagnostic items for macros
For use in Clippy, it adds diagnostic items to all the stable public macros
Clippy has lints that look for almost all of these (currently by name or path), but there are a few that aren't currently part of any lint, I could remove those if it's preferred to add them as needed rather than ahead of time
Yield means something else in the context of generators, which are
sufficiently close to iterators that it's better to avoid the
terminology collision here.
Implement `panic::update_hook`
Add a new function `panic::update_hook` to allow creating panic hooks that forward the call to the previously set panic hook, without race conditions. It works by taking a closure that transforms the old panic hook into a new one, while ensuring that during the execution of the closure no other thread can modify the panic hook. This is a small function so I hope it can be discussed here without a formal RFC, however if you prefer I can write one.
Consider the following example:
```rust
let prev = panic::take_hook();
panic::set_hook(Box::new(move |info| {
println!("panic handler A");
prev(info);
}));
```
This is a common pattern in libraries that need to do something in case of panic: log panic to a file, record code coverage, send panic message to a monitoring service, print custom message with link to github to open a new issue, etc. However it is impossible to avoid race conditions with the current API, because two threads can execute in this order:
* Thread A calls `panic::take_hook()`
* Thread B calls `panic::take_hook()`
* Thread A calls `panic::set_hook()`
* Thread B calls `panic::set_hook()`
And the result is that the original panic hook has been lost, as well as the panic hook set by thread A. The resulting panic hook will be the one set by thread B, which forwards to the default panic hook. This is not considered a big issue because the panic handler setup is usually run during initialization code, probably before spawning any other threads.
Using the new `panic::update_hook` function, this race condition is impossible, and the result will be either `A, B, original` or `B, A, original`.
```rust
panic::update_hook(|prev| {
Box::new(move |info| {
println!("panic handler A");
prev(info);
})
});
```
I found one real world use case here: 988cf403e7/src/detection.rs (L32) the workaround is to detect the race condition and panic in that case.
The pattern of `take_hook` + `set_hook` is very common, you can see some examples in this pull request, so I think it's natural to have a function that combines them both. Also using `update_hook` instead of `take_hook` + `set_hook` reduces the number of calls to `HOOK_LOCK.write()` from 2 to 1, but I don't expect this to make any difference in performance.
### Unresolved questions:
* `panic::update_hook` takes a closure, if that closure panics the error message is "panicked while processing panic" which is not nice. This is a consequence of holding the `HOOK_LOCK` while executing the closure. Could be avoided using `catch_unwind`?
* Reimplement `panic::set_hook` as `panic::update_hook(|_prev| hook)`?
Remove `&mut` from `io::read_to_string` signature
``@m-ou-se`` [realized][1] that because `Read` is implemented for `&mut impl
Read`, there's no need to take `&mut` in `io::read_to_string`.
Removing the `&mut` from the signature allows users to remove the `&mut`
from their calls (and thus pass an owned reader) if they don't use the
reader later.
r? `@m-ou-se`
[1]: https://github.com/rust-lang/rust/issues/80218#issuecomment-874322129
Inline std::os::unix::ffi::OsStringExt methods
Those methods essentially do nothing at assembly level. On Unix systems, `OsString` is represented as a `Vec` without performing any transformations.
Simplification of BigNum::bit_length
As indicated in the comment, the BigNum::bit_length function could be
optimized by using CLZ, which is often a single instruction instead a
loop.
I think the code is also simpler now without the loop.
I added some additional tests for Big8x3 and Big32x40 to ensure that
there were no regressions.
Extend const_convert to rest of blanket core::convert impls
This adds constness to all the blanket impls in `core::convert` under the existing `const_convert` feature, tracked by #88674.
Existing impls under that feature:
```rust
impl<T> const From<T> for T;
impl<T, U> const Into<U> for T where U: ~const From<T>;
impl<T> const ops::Try for Option<T>;
impl<T> const ops::FromResidual for Option<T>;
impl<T, E> const ops::Try for Result<T, E>;
impl<T, E, F> const ops::FromResidual<Result<convert::Infallible, E>> for Result<T, F> where F: ~const From<E>;
```
Additional impls:
```rust
impl<T: ?Sized, U: ?Sized> const AsRef<U> for &T where T: ~const AsRef<U>;
impl<T: ?Sized, U: ?Sized> const AsRef<U> for &mut T where T: ~const AsRef<U>;
impl<T: ?Sized, U: ?Sized> const AsMut<U> for &mut T where T: ~const AsMut<U>;
impl<T, U> const TryInto<U> for T where U: ~const TryFrom<T>;
impl<T, U> const TryFrom<U> for T where U: ~const Into<T>;
```
Partially stabilize `maybe_uninit_extra`
This covers:
```rust
impl<T> MaybeUninit<T> {
pub unsafe fn assume_init_read(&self) -> T { ... }
pub unsafe fn assume_init_drop(&mut self) { ... }
}
```
It does not cover the const-ness of `write` under `const_maybe_uninit_write` nor the const-ness of `assume_init_read` (this commit adds `const_maybe_uninit_assume_init_read` for that).
FCP: https://github.com/rust-lang/rust/issues/63567#issuecomment-958590287.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
`@m-ou-se` [realized][1] that because `Read` is implemented for `&mut impl
Read`, there's no need to take `&mut` in `io::read_to_string`.
Removing the `&mut` from the signature allows users to remove the `&mut`
from their calls (and thus pass an owned reader) if they don't use the
reader later.
[1]: https://github.com/rust-lang/rust/issues/80218#issuecomment-874322129
Add `std::error::Report` type
This is a continuation of https://github.com/rust-lang/rust/pull/90174, split into a separate PR since I cannot push to ```````@seanchen1991``````` 's fork
Simpilfy thread::JoinInner.
`JoinInner`'s `native` field was an `Option`, but that's unnecessary.
Also, thanks to `Arc::get_mut`, there's no unsafety needed in `JoinInner::join()`.
`WSADuplicateSocketW` returns 0 on success, which differs from
handle-oriented functions which return 0 on error. Use `sys::net::cvt`
to handle its return value, which handles the socket convention of
returning 0 on success, rather than `sys::cvt`, which handles the
handle-oriented convention of returning 0 on failure.
Eliminate "boxed" wording in `std::error::Error` documentation
In commit 29403ee, documentation for the methods on `std::any::Any` was
modified so that they referred to the concrete value behind the trait
object as the "inner" value. This is a more accurate wording than
"boxed": while putting trait objects inside boxes is arguably the most
common use, they can also be placed behind other pointer types like
`&mut` or `std::sync::Arc`.
This commit does the same documentation changes for `std::error::Error`.
Improve documentation for File::options to give a more likely example
`File::options().read(true).open(...)` is equivalent to just
`File::open`. Change the example to set the `append` flag instead, and
then change the filename to something more likely to be written in
append mode.
This covers:
impl<T> MaybeUninit<T> {
pub unsafe fn assume_init_read(&self) -> T { ... }
pub unsafe fn assume_init_drop(&mut self) { ... }
}
It does not cover the const-ness of `write` under
`const_maybe_uninit_write` nor the const-ness of
`assume_init_read` (this commit adds
`const_maybe_uninit_assume_init_read` for that).
FCP: https://github.com/rust-lang/rust/issues/63567#issuecomment-958590287.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Replace usages of vec![].into_iter with [].into_iter
`[].into_iter` is idiomatic over `vec![].into_iter` because its simpler and faster (unless the vec is optimized away in which case it would be the same)
So we should change all the implementation, documentation and tests to use it.
I skipped:
* `src/tools` - Those are copied in from upstream
* `src/test/ui` - Hard to tell if `vec![].into_iter` was used intentionally or not here and not much benefit to changing it.
* any case where `vec![].into_iter` was used because we specifically needed a `Vec::IntoIter<T>`
* any case where it looked like we were intentionally using `vec![].into_iter` to test it.
`File::options().read(true).open(...)` is equivalent to just
`File::open`. Change the example to set the `append` flag instead, and
then change the filename to something more likely to be written in
append mode.
In commit 29403ee, documentation for the methods on `std::any::Any` was
modified so that they referred to the concrete value behind the trait
object as the "inner" value. This is a more accurate wording than
"boxed": while putting trait objects inside boxes is arguably the most
common use, they can also be placed behind other pointer types like
`&mut` or `std::sync::Arc`.
This commit does the same documentation changes for `std::error::Error`.
As indicated in the comment, the BigNum::bit_length function could be
optimized by using CLZ, which is often a single instruction instead a
loop.
I think the code is also simpler now without the loop.
I added some additional tests for Big8x3 and Big32x40 to ensure that
there were no regressions.
Mak DefId to AccessLevel map in resolve for export
hir_id to accesslevel in resolve and applied in privacy
using local def id
removing tracing probes
making function not recursive and adding comments
Move most of Exported/Public res to rustc_resolve
moving public/export res to resolve
fix missing stability attributes in core, std and alloc
move code to access_levels.rs
return for some kinds instead of going through them
Export correctness, macro changes, comments
add comment for import binding
add comment for import binding
renmae to access level visitor, remove comments, move fn as closure, remove new_key
fmt
fix rebase
fix rebase
fmt
fmt
fix: move macro def to rustc_resolve
fix: reachable AccessLevel for enum variants
fmt
fix: missing stability attributes for other architectures
allow unreachable pub in rustfmt
fix: missing impl access level + renaming export to reexport
Missing impl access level was found thanks to a test in clippy
Make `Atomic*::from_mut` return `&mut Atomic*`
```rust
impl Atomic* {
pub fn from_mut(v: &mut bool) -> &mut Self;
// ^^^^---- previously was just a &
}
```
This PR makes `from_mut` atomic methods tracked in #76314 return unique references to atomic types, instead of shared ones. This makes `from_mut` and `get_mut` inverses of each other, allowing to undo either of them by the other.
r? `@RalfJung`
(as Ralf was [concerned](https://github.com/rust-lang/rust/issues/76314#issuecomment-955062593) about this)
Implemented const casts of raw pointers
This adds `as_mut()` method for `*const T` and `as_const()` for `*mut T`
which are intended to make casting of consts safer. This was discussed
in the [internals discussion][discussion].
Given that this is a simple change and multiple people agreed to it including `@RalfJung` I decided to go ahead and open the PR.
[discussion]: https://internals.rust-lang.org/t/casting-constness-can-be-risky-heres-a-simple-fix/15933
Add some missing `#[must_use]` to some `f{32,64}` operations
This PR adds `#[must_use]` to the following methods:
- `f32::recip`
- `f32::max`
- `f32::min`
- `f32::maximum`
- `f32::minimum`
and their equivalents in `f64`.
These methods all produce a new value without modifying the original and so are pointless to call without using the result.
Add note about non_exhaustive to variant_count
Since `variant_count` isn't returning something opaque, I thought it makes sense to explicitly call out that its return value may change for some enums.
cc #73662
Previously suggested in https://github.com/rust-lang/rfcs/issues/2854.
It makes sense to have this since `char` implements `From<u8>`. Likewise
`u32`, `u64`, and `u128` (since #79502) implement `From<char>`.
