Change PhantomData type for `BuildHasherDefault` (and more)
Changes `PhantomData<H>` to `PhantomData<fn() -> H>` for `BuildHasherDefault`. This preserves the covariance of `H`, while it lifts the currently inferred unnecessary bounds like [`H: Send` for `BuildHasherDefault<H>: Send`](https://doc.rust-lang.org/1.57.0/std/hash/struct.BuildHasherDefault.html#impl-Send), etc.
_Edit:_ Also does a similar change for `iter::Empty` and `future::Pending`.
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`.
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
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>
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.
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>`.
Rollup of 7 pull requests
Successful merges:
- #92092 (Drop guards in slice sorting derive src pointers from &mut T, which is invalidated by interior mutation in comparison)
- #92388 (Fix a minor mistake in `String::try_reserve_exact` examples)
- #92442 (Add negative `impl` for `Ord`, `PartialOrd` on `LocalDefId`)
- #92483 (Stabilize `result_cloned` and `result_copied`)
- #92574 (Add RISC-V detection macro and more architecture instructions)
- #92575 (ast: Always keep a `NodeId` in `ast::Crate`)
- #92583 (⬆️ rust-analyzer)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Add RISC-V detection macro and more architecture instructions
This pull request includes:
- Update `stdarch` dependency to include ratified RISC-V supervisor and hypervisor instruction intrinsics which is useful in Rust kernel development
- Add macro `is_riscv_feature_detected!`
- Modify impl of `core::hint::spin_loop` to comply with latest version of `core::arch`
After this update, users may now develop RISC-V kernels and user applications more freely.
r? `@Amanieu`
Drop guards in slice sorting derive src pointers from &mut T, which is invalidated by interior mutation in comparison
I tried to run https://github.com/rust-lang/miri-test-libstd on `alloc` with `-Zmiri-track-raw-pointers`, and got a failure on the test `slice::panic_safe`. The test failure has nothing to do with panic safety, it's from how the test tests for panic safety.
I minimized the test failure into this very silly program:
```rust
use std::cell::Cell;
use std::cmp::Ordering;
#[derive(Clone)]
struct Evil(Cell<usize>);
fn main() {
let mut input = vec![Evil(Cell::new(0)); 3];
// Hits the bug pattern via CopyOnDrop in core
input.sort_unstable_by(|a, _b| {
a.0.set(0);
Ordering::Less
});
// Hits the bug pattern via InsertionHole in alloc
input.sort_by(|_a, b| {
b.0.set(0);
Ordering::Less
});
}
```
To fix this, I'm just removing the mutability/uniqueness where it wasn't required.
Rollup of 7 pull requests
Successful merges:
- #91587 (core::ops::unsize: improve docs for DispatchFromDyn)
- #91907 (Allow `_` as the length of array types and repeat expressions)
- #92515 (RustWrapper: adapt for an LLVM API change)
- #92516 (Do not use deprecated -Zsymbol-mangling-version in bootstrap)
- #92530 (Move `contains` method of Option and Result lower in docs)
- #92546 (Update books)
- #92551 (rename StackPopClean::None to Root)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Move `contains` method of Option and Result lower in docs
Follow-up to #92444 trying to get the `Option` and `Result` rustdocs in better shape.
This addresses the request in https://github.com/rust-lang/rust/issues/62358#issuecomment-645676285. The `contains` methods are previously too high up in the docs on both `Option` and `Result` — stuff like `ok` and `map` and `and_then` should all be featured higher than `contains`. All of those are more ubiquitously useful than `contains`.
- Do not `#[doc(hidden)]` the `#[derive]` macro attribute
- Add a link to the reference section to `derive`'s inherent docs
- Do the same for `#[test]` and `#[global_allocator]`
- Fix `GlobalAlloc` link (why is it on `core` and not `alloc`?)
- Try `no_inline`-ing the `std` reexports from `core`
- Revert "Try `no_inline`-ing the `std` reexports from `core`"
- Address PR review
- Also document the unstable macros
Consolidate Result's and Option's methods into fewer impl blocks
`Result`'s and `Option`'s methods have historically been separated up into `impl` blocks based on their trait bounds, with the bounds specified on type parameters of the impl block. I find this unhelpful because closely related methods, like `unwrap_or` and `unwrap_or_default`, end up disproportionately far apart in source code and rustdocs:
<pre>
impl<T> Option<T> {
pub fn unwrap_or(self, default: T) -> T {
...
}
<img alt="one eternity later" src="https://user-images.githubusercontent.com/1940490/147780325-ad4e01a4-c971-436e-bdf4-e755f2d35f15.jpg" width="750">
}
impl<T: Default> Option<T> {
pub fn unwrap_or_default(self) -> T {
...
}
}
</pre>
I'd prefer for method to be in as few impl blocks as possible, with the most logical grouping within each impl block. Any bounds needed can be written as `where` clauses on the method instead:
```rust
impl<T> Option<T> {
pub fn unwrap_or(self, default: T) -> T {
...
}
pub fn unwrap_or_default(self) -> T
where
T: Default,
{
...
}
}
```
*Warning: the end-to-end diff of this PR is computed confusingly by git / rendered confusingly by GitHub; it's practically impossible to review that way. I've broken the PR into commits that move small groups of methods for which git behaves better — these each should be easily individually reviewable.*
Track caller of slice split and swap
Improves error location for `slice.split_at*()` and `slice.swap()`.
These are generic inline functions, so the `#[track_caller]` on them is free — only changes a value of an argument already passed to panicking code.
Add `#[inline]` modifier to `TypeId::of`
It was already inlined but it happened only in 4th InlinerPass on my testcase.
With `#[inline]` modifier it happens on 2nd pass.
Closes#74362
disable test with self-referential generator on Miri
Running the libcore test suite in Miri currently fails due to the known incompatibility of self-referential generators with Miri's aliasing checks (https://github.com/rust-lang/unsafe-code-guidelines/issues/148). So let's disable that test in Miri for now.
Use panic() instead of panic!() in some places in core.
See https://github.com/rust-lang/rust/pull/92068 and https://github.com/rust-lang/rust/pull/92140.
This avoids the `panic!()` macro in a few potentially hot paths. This becomes more relevant when switching `core` to Rust 2021, as it'll avoid format_args!() and save some compilation time. (It doesn't make a huge difference, but still.) (Also the errors in const panic become slightly nicer.)
Allow reverse iteration of lowercase'd/uppercase'd chars
The PR implements `DoubleEndedIterator` trait for `ToLowercase` and `ToUppercase`.
This enables reverse iteration of lowercase/uppercase variants of character sequences.
One of use cases: determining whether a char sequence is a suffix of another one.
Example:
```rust
fn endswith_ignore_case(s1: &str, s2: &str) -> bool {
for eob in s1
.chars()
.flat_map(|c| c.to_lowercase())
.rev()
.zip_longest(s2.chars().flat_map(|c| c.to_lowercase()).rev())
{
match eob {
EitherOrBoth::Both(c1, c2) => {
if c1 != c2 {
return false;
}
}
EitherOrBoth::Left(_) => return true,
EitherOrBoth::Right(_) => return false,
}
}
true
}
```
