Easy change.

@rustbot label: +llvm-main

Tweak variable names in the deadlock example to remove any potential
confusion that the behavior is somehow shadowing-related.

…piler-errors

match lowering: build the `Place` instead of keeping a `PlaceBuilder` around

Outside of `MatchPair::new` we don't construct new places, so we don't need to keep a `PlaceBuilder` around.

A bit annoyingly we have to store an `Option<Place>` even though it's never `None` after simplification, but the alternative would be to re-entangle `MatchPair` construction and simplification and I'd rather not do that.

…kingjubilee

Unix: Support more platforms with `preadv` and `pwritev`

- `aix`, `dragonfly` and `openbsd` with direct call
- `watchos` with weak linkage

cc rust-lang#89517

…bilee

std library thread.rs: fix NetBSD code for ILP32 CPUs.

…ingjubilee

`UnixStream`: override `read_buf`

Split from rust-lang#122441

r? ``@workingjubilee``

…gjubilee

RustWrapper: update call for llvm/llvm-project@44d037cc258dcf179d2c48…

…c93996bb406ecd0fae

Easy change.

`@rustbot` label: +llvm-main

Implement `Vec::pop_if`

This PR adds `Vec::pop_if` to the public API, behind the `vec_pop_if` feature.

```rust
impl<T> Vec<T> {
    pub fn pop_if<F>(&mut self, f: F) -> Option<T>
        where F: FnOnce(&mut T) -> bool;
}
```

Tracking issue: rust-lang#122741

## Open questions

- [ ] Should the first unit test be split up?
- [ ] I don't see any guidance on ordering of methods in impl blocks, should I move the method elsewhere?

…ilee

Update `RwLock` deadlock example to not use shadowing

Tweak variable names in the deadlock example to remove any potential confusion that the behavior is somehow shadowing-related.