Implement indexing slices with pairs of core::ops::Bound<usize>
Closes#49976.
I am not sure about code duplication between `check_range` and `into_maybe_range`. Should be former implemented in terms of the latter? Also this PR doesn't address code duplication between `impl SliceIndex for Range*`.
Format `Struct { .. }` on one line even with `{:#?}`.
The result of `debug_struct("A").finish_non_exhaustive()` before this change:
```
A {
..
}
```
And after this change:
```
A { .. }
```
If there's any fields, the result stays unchanged:
```
A {
field: value,
..
}
fix 'const-stable since' for NonZeroU*::new_unchecked
For the unsigned `NonZero` types, `new_unchecked` was const-stable from the start with https://github.com/rust-lang/rust/pull/50808. Fix the docs to accurately reflect that.
I think this `since` is also incorrect:
```rust
#[stable(feature = "from_nonzero", since = "1.31.0")]
impl From<$Ty> for $Int {
```
The signed nonzero types were only stabilized in 1.34, so that `From` impl certainly didn't exist before. But I had enough of digging through git histories after I figured out when `new_unchecked` became const-stable...^^
Replace all `fmt.pad` with `debug_struct`
This replaces any occurrence of:
- `f.pad("X")` with `f.debug_struct("X").finish()`
- `f.pad("X { .. }")` with `f.debug_struct("X").finish_non_exhaustive()`
This is in line with existing formatting code such as
1255053067/library/std/src/sync/mpsc/mod.rs (L1470-L1475)
Deprecate the core::raw / std::raw module
It only contains the `TraitObject` struct which exposes components of wide pointer. Pointer metadata APIs are designed to replace this: https://github.com/rust-lang/rust/issues/81513
Add some #[inline(always)] to arithmetic methods of integers
I tried to add it only to methods which return results of intrinsics and don't have any branching.
Branching could made performance of debug builds (`-Copt-level=0`) worse.
Main goal of changes is allowing wider optimizations in `-Copt-level=1`.
Closes: https://github.com/rust-lang/rust/issues/75598
r? `@nagisa`
No compiler changes as part of this -- just new unstable traits and impls thereof.
The goal here is to add the things that aren't going to break anything, to keep the feature implementation simpler in the next PR.
add lint deref_nullptr detecting when a null ptr is dereferenced
fixes#83856
changelog: add lint that detect code like
```rust
unsafe {
&*core::ptr::null::<i32>()
};
unsafe {
addr_of!(std::ptr::null::<i32>())
};
let x: i32 = unsafe {*core::ptr::null()};
let x: i32 = unsafe {*core::ptr::null_mut()};
unsafe {*(0 as *const i32)};
unsafe {*(core::ptr::null() as *const i32)};
```
```
warning: Dereferencing a null pointer causes undefined behavior
--> src\main.rs:5:26
|
5 | let x: i32 = unsafe {*core::ptr::null()};
| ^^^^^^^^^^^^^^^^^^
| |
| a null pointer is dereferenced
| this code causes undefined behavior when executed
|
= note: `#[warn(deref_nullptr)]` on by default
```
Limitation:
It does not detect code like
```rust
const ZERO: usize = 0;
unsafe {*(ZERO as *const i32)};
```
or code where `0` is not directly a literal
I tried to add it only to methods which return results of intrinsics and don't have any branching.
Branching could made performance of debug builds (`-Copt-level=0`) worse.
Main goal of changes is allowing wider optimizations in `-Copt-level=1`.
Closes: https://github.com/rust-lang/rust/issues/75598
Add note about reverting a workaround in the future
The root cause was fixed upstream in LLVM main. This adds a reminder to revert the workaround once the LLVM rustc depends on is new enough. Since I'm not sure how such optimizations get routed to LLVM releases, I used the conservative assumption that it will only show up with LLVM 13.