borrowck diagnostics cleanup: remove an unused and a barely-used field
This removes the fields `fr_is_local` and `outlived_fr_is_local` from the struct `ErrorConstraintInfo`. `fr_is_local` was fully unused, but wasn't caught by dead-code analysis. For symmetry, and since `outlived_fr_is_local` was used only once and is easy to recompute, I've removed it too. That makes its one use a bit longer, but constructing/destructuring an `ErrorConsraintInfo` now fits on one line.
Prepare standard library for Rust 2024 migration
This includes a variety of commits preparing the standard library for migration to Rust 2024.
The actual migration is blocked on a few things, so I wanted to get this out of the way in a relatively digestable PR.
Stabilize `const_is_char_boundary` and `const_str_split_at`.
Tracking issues: #131516, #131518
Stabilized const API:
```rs
// in `core`
impl str {
// const_is_char_boundary feature
const fn is_char_boundary(&self, index: usize) -> bool;
// const_str_split_at feature, depends on const_is_char_boundary
const fn split_at(&self, mid: usize) -> (&str, &str);
const fn split_at_mut(&mut self, mid: usize) -> (&mut str, &mut str);
const fn split_at_checked(&self, mid: usize) -> Option<(&str, &str)>;
const fn split_at_mut_checked(&mut self, mid: usize) -> Option<(&mut str, &mut str)>;
}
```
This will allow safely splitting string slices during const-eval.
Closes#131516, Closes#131518
This will need FCP.
r? libs-api
IIUC these do not use any new const language features (i.e. they are implementable manually on stable 1.83.0 using `unsafe`: [playground link](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=3679632cd1041084796241b7ac8edfbd)).
Cc ``@rust-lang/wg-const-eval`` (I don't know if I have the permissions for this ping; if not, someone else please ping wg-const-eval if it is necessary)
Rollup of 9 pull requests
Successful merges:
- #135778 (account for `c_enum_min_bits` in `multiple-reprs` UI test)
- #136052 (Correct comment for FreeBSD and DragonFly BSD in unix/thread)
- #136886 (Remove the common prelude module)
- #136956 (add vendor directory to .gitignore)
- #136958 (Fix presentation of purely "additive" replacement suggestion parts)
- #136967 (Use `slice::fill` in `io::Repeat` implementation)
- #136976 (alloc boxed: docs: use MaybeUninit::write instead of as_mut_ptr)
- #137007 (Emit MIR for each bit with on `dont_reset_cast_kind_without_updating_operand`)
- #137008 (Move code into `rustc_mir_transform`)
r? `@ghost`
`@rustbot` modify labels: rollup
These functions were changed to be safe in
https://github.com/rust-lang/rust/pull/127763, but this particular UWP
version was missed. Otherwise this causes unnecessary unsafe block
warnings/errors.
Move code into `rustc_mir_transform`
I found two modules in other crates that are better placed in `rustc_mir_transform`, because that's the only crate that uses them.
r? ``@matthewjasper``
Emit MIR for each bit with on `dont_reset_cast_kind_without_updating_operand`
PR #136450 introduced a diff that includes a pointer-sized alloc. This doesn't cause any problems on the compiler test suite but it affects the test suite that ferrocene has for `aarch64-unknown-none` as the snapshot of the diff only includes a 32-bit alloc even though this should be a 64-bit alloc on `aarch64-unknown-none`.
r? ``@compiler-errors``
alloc boxed: docs: use MaybeUninit::write instead of as_mut_ptr
In the deferred initialization pattern, the docs were needlessly going through `as_mut_ptr().write()` to initialize, which is unnecessary use of a pointer, needs to be inside an `unsafe` block, and may weaken alias analysis.
Fix presentation of purely "additive" replacement suggestion parts
#127541 changes replacement suggestions to use the "diff" view always, which I think is really verbose in cases where a replacement snippet is a "superset" of the snippet that is being replaced.
Consider:
```
LL - Self::Baz: Clone,
LL + Self::Baz: Clone, T: std::clone::Clone
```
In this code, we suggest replacing `", "` with `", T: std::clone::Clone"`. This is a consequence of how the snippet is constructed. I believe that since the string that is being replaced is a subset of the replacement string, it's not providing much value to present this as a diff. Users should be able to clearly understand what's being suggested here using the `~` underline view we've been suggesting for some time now.
Given that this affects ~100 tests out of the ~1000 UI tests affected, I expect this to be a pretty meaningful improvement of the fallout of #127541.
---
In the last commit, this PR also "trims" replacement parts so that they are turned into their purely additive subset, if possible. See the diff for what this means.
---
r? estebank
Remove the common prelude module
This fixes the issues described in https://github.com/rust-lang/rust/issues/136102. Primarily, this resolves some issues with how the documentation for the prelude is generated:
- It avoids showing "unstable" for macros in the prelude that are actually stable.
- Avoids duplication of some pages due to the previous lack of `doc(no_inline)`.
- Makes the different edition preludes consistent, and sets a pattern that can be used by future editions.
We may need to rearrange these modules in the future if we decide to remove anything from the prelude again. If we do, I think we should look into a different solution that avoids the documentation problems.
Closes https://github.com/rust-lang/rust/issues/136102
Set both `nuw` and `nsw` in slice size calculation
There's an old note in the code to do this, and now that [LLVM-C has an API for it](f0b8ff1251/llvm/include/llvm-c/Core.h (L4403-L4408)), we might as well. And it's been there since what looks like LLVM 17 de9b6aa341 so doesn't even need to be conditional.
(There's other places, like `RawVecInner` or `Layout`, that might want to do things like this too, but I'll leave those for a future PR.)
Change description from compiletest to regression test
Co-authored-by: 许杰友 Jieyou Xu (Joe) <39484203+jieyouxu@users.noreply.github.com>
Improve test name, location, and description
Update tests/ui/impl-trait/impl-fn-rpit-opaque-107883.rs
Co-authored-by: waffle <waffle.lapkin@gmail.com>
