Changed because it's not obvious how to get from the previously used URL to the documentation-specific content.

This is partly because the original URL was previously changed to point to different content:

 * https://github.com/rust-lang/rust/pull/74037/files#diff-242481015141f373dcb178e93cffa850L88

 * rust-lang@3f6928f#diff-6a3371457528722a734f3c51d9238c13L12

…er of UTF8 bytes.

Fixed it by inlining it in the two places where the count is used and simplified the logic there.

A few architectures in `os::linux::raw` import `libc::stat`, rather than
defining that type directly. However, that also imports the _function_
called `stat`, which makes this doc link ambiguous:

    error: `crate::os::linux::raw::stat` is both a struct and a function
      --> library/std/src/os/linux/fs.rs:21:19
       |
    21 |     /// [`stat`]: crate::os::linux::raw::stat
       |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^ ambiguous link
       |
       = note: `-D broken-intra-doc-links` implied by `-D warnings`
    help: to link to the struct, prefix with the item type
       |
    21 |     /// [`stat`]: struct@crate::os::linux::raw::stat
       |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    help: to link to the function, add parentheses
       |
    21 |     /// [`stat`]: crate::os::linux::raw::stat()
       |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

We want the `struct`, so it's now prefixed accordingly.

s/abitrary/arbitrary/

This got out of sync when the version was bumped last time.

Long-term we may want to find an easier way to maintain this that
doesn't require bumping the version in three different places. Off the
top of my head I can't think of anything, though.

Co-authored-by: Joshua Nelson <joshua@yottadb.com>

They should take boolean values and the current placeholders are confusing, at least for me.

Link to documentation-specific guidelines.

Changed contribution information URL because it's not obvious how to get from the current URL to the documentation-specific content.

The current URL points to this "Getting Started" page, which contains nothing specific about documentation[*] and instead launches into how to *build* `rustc` which is not a strict prerequisite for contributing documentation fixes:

 * https://rustc-dev-guide.rust-lang.org/getting-started.html

[*] The most specific content is a "Writing documentation" bullet point which is not itself a link to anything (I guess a patch for that might be helpful too).

### Why?

Making this change will make it easier for people who wish to make small "drive by" documentation fixes (and read contribution guidelines ;) ) which I find are often how I start contributing to a project. (Exhibit A: rust-lang#77050 :) )

### Background

My impression is the change of content linked is an unintentional change due to a couple of other changes:

 * Originally, the link pointed to  `contributing.md` which started with a "table of contents" linking to each section. But the content in `contributing.md` was removed and replaced with a link to the "Getting Started" section here:

    * rust-lang@3f6928f#diff-6a3371457528722a734f3c51d9238c13L1

   But the changed link doesn't actually point to the equivalent content, which is now located here:

    * https://rustc-dev-guide.rust-lang.org/contributing.html

   (If the "Guide to Rustc Development" is now considered the canonical location of "How to Contribute" content it might be a good idea to merge some of the "Contributing" Introduction section into the "Getting Started" section.)

 * This was then compounded by changing the link from `contributing.md` to  `contributing.html` here:

     * https://github.com/rust-lang/rust/pull/74037/files#diff-242481015141f373dcb178e93cffa850L88

    In order to even find the new location of the previous `contributing.md` content I ended up needing to do a GitHub search of the `rust-lang` org for the phrase "Documentation improvements are very welcome". :D

…rError, r=varkor

Cleanup of `eat_while()` in lexer

The size of a lexer Token was inflated by the largest `TokenKind` variants `LiteralKind::RawStr` and `RawByteStr`, because
* it used `usize` although `u32` is sufficient in rustc, since crates must be smaller than 4GB,
* and it stored the 20 bytes big `RawStrError` enum for error reporting.

If a raw string is invalid, it now needs to be reparsed to get the `RawStrError` data, but that is a very cold code path.

Technically this breaks other tools that depend on rustc_lexer because they are now also restricted to a max file size of 4GB. But this shouldn't matter in practice, and rustc_lexer isn't stable anyway.

Can I also get a perf run?

Edit: This makes no difference in performance. The PR now only contains a small cleanup.

Link Vec leak doc to Box

…t, r=Amanieu

fix __rust_alloc_error_handler comment

`__rust_alloc_error_handler` was added in the same `extern` block as the allocator functions, but the comment there was not actually correct for `__rust_alloc_error_handler`. So move it down to the rest of the default allocator handling with a fixed comment. At least the comment reflects my understanding of what happens, please check carefully. :)

r? @Amanieu Cc @haraldh

…henkov

Dead code cleanup in windows-gnu std

Closes rust-lang#77622

This is the only leftover I could find.

…matthewjasper

Add TraitDef::find_map_relevant_impl

This PR adds a method to `TraitDef`. While `for_each_relevant_impl` covers the general use case, sometimes it's not necessary to scan through all the relevant implementations, so this PR introduces a new method, `find_map_relevant_impl`. I've also replaced the `for_each_relevant_impl` calls where possible.

I'm hoping for a tiny bit of efficiency gain here and there.

Clarify the debug-related values should take boolean

rust-lang#76588 tweaked their placeholders but these values should take boolean and the current placeholders are confusing, at least for me.

doc: disambiguate stat in MetadataExt::as_raw_stat

A few architectures in `os::linux::raw` import `libc::stat`, rather than
defining that type directly. However, that also imports the _function_
called `stat`, which makes this doc link ambiguous:

    error: `crate::os::linux::raw::stat` is both a struct and a function
      --> library/std/src/os/linux/fs.rs:21:19
       |
    21 |     /// [`stat`]: crate::os::linux::raw::stat
       |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^ ambiguous link
       |
       = note: `-D broken-intra-doc-links` implied by `-D warnings`
    help: to link to the struct, prefix with the item type
       |
    21 |     /// [`stat`]: struct@crate::os::linux::raw::stat
       |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    help: to link to the function, add parentheses
       |
    21 |     /// [`stat`]: crate::os::linux::raw::stat()
       |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

We want the `struct`, so it's now prefixed accordingly.

Fix typo in error code description

s/abitrary/arbitrary/

…orino

Update `changelog-seen` in config.toml.example

This got out of sync when the version was bumped last time in rust-lang#77133

Long-term we may want to find an easier way to maintain this that
doesn't require bumping the version in three different places. Off the
top of my head I can't think of anything, though. It _is_ documented in src/bootstrap/README.md, although I don't know how many people read that.

r? @Mark-Simulacrum
cc @spastorino