These structs have misleading names.  An ExitStatus[Error] is actually
a Unix wait status; an ExitCode is actually an exit status.

The Display impls are fixed, but the Debug impls are still misleading,
as reported in rust-lang#74832.

Fix this by pretending that these internal structs are called
`unix_exit_status` and `unix_wait_status` as applicable.  (We can't
actually rename the structs because of the way that the cross-platform
machinery works: the names are cross-platform.)

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

This also makes `<[T; N]>::as_slice` const due to its trivial nature.

namely `Vec::extend_from_within`

fix: move test that require mut to another

Adding TODOs for Option::take and Option::copied

TODO to FIXME + moving const stability under normal

Moving const stability attr under normal stab attr

move more rustc stability attributes

- Make clear that the `Pointer` trait is related to formatting
- Make clear that `&T` (shared reference) implements `Send` (if `T: Send + Sync`)

Co-authored-by: fmease <liehr.exchange@gmx.net>

Refs: rust-lang#85223

For some reason unboxed_closures supresses the feature gate for
min_specialization when implementing TrustedStep. min_specialization is
the true feature that is used.

On MinGW toolchains the various features (such as function sections)
necessary to eliminate dead function references are disabled due to
various bugs. This means that the windows sockets library will most
likely remain linked to any mingw toolchain built program that also
utilizes libstd.

That said, I made an attempt to also enable `function-sections` and
`--gc-sections` during my experiments, but the symbol references
remained, sadly.

This is cleaner and removes an unstable feature usage

Fixes rust-lang#55825

…plett

Add `Ipv6Addr::is_benchmarking`

This PR adds the unstable method `Ipv6Addr::is_benchmarking`. This method is added for parity with `Ipv4Addr::is_benchmarking`, and I intend to use it in a future rework of `Ipv6Addr::is_global` (edit: rust-lang#86634) to more accurately follow the [IANA Special Address Registry](https://www.iana.org/assignments/iana-ipv6-special-registry/iana-ipv6-special-registry.xhtml) (like is done in `Ipv4Addr::is_global`).

With `Ipv6Addr::is_benchmarking` and `Ipv4Addr::is_benchmarking` now both existing, `IpAddr::is_benchmarking` is also added.

…-replace, r=joshtriplett

const fn for option copied, take & replace

Tracking issue: [rust-lang#67441](rust-lang#67441)

Adding const fn for the copied, take and replace method of Option. Also adding necessary unit test.

It's my first contribution so I am pretty sure I don't know what I'm doing but there's a first for everything!

BTree: refine some comments

…metics_as_const, r=joshtriplett

Mark unsafe methods NonZero*::unchecked_(add|mul) as const.

Now that rust-lang/rfcs#3016 has landed, these two unstable `std` function can be marked `const`, according to this detail of rust-lang#84186.

…block-std, r=dtolnay

Remove unnecessary unsafe block in `process_unix`

Because it's nested under this unsafe fn!

This block isn't detected as unnecessary because of a bug in the compiler: rust-lang#88260.

Manual Debug for Unix ExitCode ExitStatus ExitStatusError

These structs have misleading names.  An ExitStatus[Error] is actually a Unix wait status; an ExitCode is actually an exit status.  These misleading names appear in the `Debug` output.

The `Display` impls on Unix have been improved, but the `Debug` impls are still misleading, as reported in rust-lang#74832.

Fix this by pretending that these internal structs are called `unix_exit_status` and `unix_wait_status` as applicable.  (We can't actually rename the structs because of the way that the cross-platform machinery works: the names are cross-platform.)

After this change, this program
```
#![feature(exit_status_error)]
fn main(){
    let x = std::process::Command::new("false").status().unwrap();
    dbg!(x.exit_ok());
    eprintln!("x={:?}",x);
}
```
produces this output
```
[src/main.rs:4] x.exit_ok() = Err(
    ExitStatusError(
        unix_wait_status(
            256,
        ),
    ),
)
x=ExitStatus(unix_wait_status(256))
```

Closes rust-lang#74832

…oshtriplett

Partially stabilize `array_methods`

This stabilizes `<[T; N]>::as_slice` and `<[T; N]>::as_mut_slice`, which is forms part of the `array_methods` feature: rust-lang#76118.

This also makes `<[T; N]>::as_slice` const due to its trivial nature.

Makes docs for references a little less confusing

- Make clear that the `Pointer` trait is related to formatting
- Make clear that the `Pointer` trait is implemented for references (previously it was confusing to first see that it's implemented and then see it in "expect")
- Make clear that `&T` (shared reference) implements `Send` (if `T: Send + Sync`)

Add missing `# Panics` section to `Vec` method

namely `Vec::extend_from_within`

…llot

Remove some feature gates

The first commit removes various feature gates that are unused. The second commit replaces some `Fn` implementations with `Iterator` implementations, which is much cleaner IMO. The third commit replaces an unboxed_closures feature gate with min_specialization. For some reason the unboxed_closures feature gate suppresses the min_specialization feature gate from triggering on an `TrustedStep` impl. The last comment just turns a regular comment into a doc comment as drive by cleanup. I can move it to a separate PR if preferred.

Fix link in Ipv6Addr::to_ipv4 docs

Fix typos in rustdoc/lints

This PR merely fixes a few typos in a recently introduced change :)

Refs: rust-lang#85223

Only register `WSACleanup` if `WSAStartup` is actually ever called

See rust-lang#85595

Fixes rust-lang#85441

…mulacrum

Add regression test for spurious const error with NLL

Fixes rust-lang#55825