Co-authored-by: 许杰友 Jieyou Xu (Joe) <[email protected]>

rust-lang#150129 reworked this field to use `bool` instead of `usize`, which is awesome!
But the field's comment has a leftover note in it which is no longer true, and that needs to be removed.

…akcheck

…r=clubby789

Fix alias path for rustdoc

I ran this command:

```console
x build --stage 1  --skip rustdoc
Building bootstrap
   Compiling bootstrap v0.0.0 (/Users/yukang/rust/src/bootstrap)
    Finished `dev` profile [unoptimized] target(s) in 1.08s
/Users/yukang/rust/build/aarch64-apple-darwin/ci-llvm/bin/llvm-strip does not exist; skipping copy
Building stage1 compiler artifacts (stage0 -> stage1, aarch64-apple-darwin)
    Finished `release` profile [optimized + debuginfo] target(s) in 0.45s
Creating a sysroot for stage1 compiler (use `rustup toolchain link 'name' build/host/stage1`)
Building stage1 library artifacts{alloc, compiler_builtins, core, panic_abort, panic_unwind, proc_macro, rustc-std-workspace-core, std, std_detect, sysroot, test, unwind} (stage1 -> stage1, aarch64-apple-darwin)
    Finished `dist` profile [optimized + debuginfo] target(s) in 0.10s
Skipping Set({build::src/tools/rustdoc}) because it is excluded
Building stage1 rustdoc_tool_binary (stage0 -> stage1, aarch64-apple-darwin)
    Finished `release` profile [optimized + debuginfo] target(s) in 0.19s
```

expect all `rustdoc` related compiling phase will be exlcuded, but from the log we can see `rustdoc_tool_binary` is still compiled.

`src/tools/rustdoc` and `src/librustdoc` are documented as aliases in path set here:
https://github.com/rust-lang/rust/blob/a25435bcf7cfc9b953d356eda3a51db8da9e3386/src/bootstrap/src/core/builder/mod.rs#L355-L360

we can also see here two paths are treated as alias:
https://github.com/rust-lang/rust/blob/a25435bcf7cfc9b953d356eda3a51db8da9e3386/src/bootstrap/src/core/build_steps/check.rs#L818-L822

but bootstrap registered them as two different sets with `.path(..).path(...)`:
https://github.com/rust-lang/rust/blob/a25435bcf7cfc9b953d356eda3a51db8da9e3386/src/bootstrap/src/core/build_steps/tool.rs#L691-L693

That meant commands like `x build --skip rustdoc`, `--skip src/tools/rustdoc`, or `--skip src/librustdoc` only excluded one side.

`-Znext-solver` Ignore region constraints from the nested goals in leakcheck

Fixes rust-lang/trait-system-refactor-initiative#251
Fixes rust-lang#140577
Fixes rust-lang#153596

…pratt

`bufreader::Buffer`: Remove leftover note about `initialized` field

Just a boring little doc fix! : v)

rust-lang#150129 reworked the `initialized` field to be a `bool` instead of a `usize`.
And then rust-lang#155314 reworked this field's comment (among other things).
But, there's still a leftover note in the comment, which no longer makes sense:
``Note that while this often the same as `filled`, it doesn't need to be.``
This is referencing that back when `initialized` was a `usize`, it was common for it to have the same value as `filled`.

----

Fun fact: there's a typo in the note too! It's missing an "is" before or after "often".

…r=joshtriplett

Map `WSAESHUTDOWN` to `io::ErrorKind::BrokenPipe`

As discussed in [#t-libs > WSAESHUTDOWN error on Windows](https://rust-lang.zulipchat.com/#narrow/channel/219381-t-libs/topic/WSAESHUTDOWN.20error.20on.20Windows/with/591883531), this adds the mapping for `WSAESHUTDOWN` on Windows to `io::ErrorKind::BrokenPipe`.

r? RalfJung