Rollup of 6 pull requests

Successful merges:

 - #101889 (doc: rewrite doc for uint::{carrying_add,borrowing_sub})
 - #102507 (More slice::partition_point examples)
 - #103164 (rustdoc: remove CSS ``@media` (min-width: 701px)`)
 - #103189 (Clean up code-color and headers-color rustdoc GUI tests)
 - #103203 (Retrieve LLVM version from llvm-filecheck binary if it is not set yet)
 - #103204 (Add some more autolabels)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Clean up rustdoc startup

Startup is pretty hairy, in both rustdoc and rustc. The first commit here improves the rustdoc situation quite a bit. The remaining commits are smaller but also help.

Best reviewed one commit at a time.

r? `@jyn514`

By moving `RenderOptions` out of `Option`, because the two structs' uses
are almost entirely separate.

The only complication is that `unstable_features` is needed in both
structs, but it's a tiny `Copy` type so its duplication seems fine.

It turns out `markdown::render` is more complex than it first appears,
because it can invoke `doctest::make_test`, which requires session
globals and a thread pool.

So this commit changes it to use `interface::run_compiler`. Three of the
four paths in `main_args` now use `interface::run_compiler`.

This avoids the need for a degenerate `Lrc::get_mut` call.

It has a single call site.

It has a single call site, and removing it slightly improves the
confusing tangle of nested closures present at startup.

There is no longer any need for them to be separate.

rustc's startup has several layers, including:
- `interface::run_compiler` passes a closure, `f`, to
  `run_in_thread_pool_with_globals`, which creates a thread pool, sets
  up session globals, and passes `f` to `create_compiler_and_run`.
- `create_compiler_and_run` creates a `Session`, a `Compiler`, sets the
  source map, and calls `f`.

rustdoc is a bit different.
- `main_args` calls `main_options` via
  `run_in_thread_pool_with_globals`, which (again) creates a thread pool
  (hardcoded to a single thread!) and sets up session globals.
- `main_options` has four different paths.
  - The second one calls `interface::run_compiler`, which redoes the
    `run_in_thread_pool_with_globals`! This is bad.
  - The fourth one calls `interface::create_compiler_and_run`, which is
    reasonable.
  - The first and third ones don't do anything of note involving the
    above functions, except for some symbol interning which requires
    session globals.

In other words, rustdoc calls into `rustc_interface` at three different
levels. It's a bit confused, and feels like code where functionality has
been added by different people at different times without fully
understanding how the globally accessible stuff is set up.

This commit tidies things up. It removes the
`run_in_thread_pool_with_globals` call in `main_args`, and adjust the
four paths in `main_options` as follows.
- `markdown::test` calls `test::test_main`, which provides its own
  parallelism and so doesn't need a thread pool. It had one small use of
  symbol interning, which required session globals, but the commit
  removes this.
- `doctest::run` already calls `interface::run_compiler`, so it doesn't
  need further adjustment.
- `markdown::render` is simple but needs session globals for interning
  (which can't easily be removed), so it's now wrapped in
  `create_session_globals_then`.
- The fourth path now uses `interface::run_compiler`, which is
  equivalent to the old `run_in_thread_pool_with_globals` +
  `create_compiler_and_run` pairing.

Add some more autolabels

Retrieve LLVM version from llvm-filecheck binary if it is not set yet

In `rustc_codegen_gcc`, we run the `ASM` test suite. The problem is that, if a too recent version of the `llvm-filecheck` binary is provided, an extra argument needs to be passed and the to detect this version, it currently only expects a `--llvm-version` argument. With this, the version can be determined directly from the `llvm-filecheck` binary.

r? ``@Amanieu``

Clean up code-color and headers-color rustdoc GUI tests

r? ``@notriddle``

rustdoc: remove CSS `@media (min-width: 701px)`

The two rules within it can and should be done without the separate media query:

  * There ain't no rule saying a viewport can't be `700.5px` wide, since hardware pixels can be finer than CSS pixels.

    <details><summary>Screenshot</summary>

    ![image](https://user-images.githubusercontent.com/1593513/196283804-e946fbe3-d914-4819-ba2d-b4a6a07f190a.png)

    </details>

  * The rule for the first example-wrap child should probably apply on mobile.

    <details><summary>Screenshots</summary>

    ## Before

    ![rustdoc-before](https://user-images.githubusercontent.com/1593513/196282813-88b861c7-7b05-4de5-a421-914396f86a04.png)

    ## After

    ![rustdoc-after](https://user-images.githubusercontent.com/1593513/196282842-e57760c2-72d5-4dad-94f5-1d7175043326.png)

    </details>

  * The rule for the source sidebar is overriden by the mobile rule setting `max-width: 100vw`, so it can be merged with the rest of the styles.

More slice::partition_point examples

After seeing the discussion of `binary_search` vs `partition_point` in #101999, I thought some more example code could be helpful.

doc: rewrite doc for uint::{carrying_add,borrowing_sub}

Reword the documentation for bigint helper methods `uint::{carrying_add,borrowing_sub}` (#85532).

The examples were also rewritten to demonstrate how the methods can be used in bignum arithmetic. No loops are used in the examples, but the variable names were chosen to include indices so that it is clear how this can be used in a loop if required.

Also, previously `carrying_add` had an example to say that if the input carry is false, the method is equivalent to `overflowing_add`. While the note was kept, the example was removed and an extra note was added to make sure this equivalence is not assumed for signed integers as well.

The illumos linker does not support --strip-debug

When building and testing rust 1.64.0 on illumos, we saw a large number of failing tests associated with:

```
   = note: ld: fatal: unrecognized option '--strip-debug'
           ld: fatal: use the -z help option for usage information
           collect2: error: ld returned 1 exit status
```

The illumos linker does not support the `--strip-debug` option (although it does support `--strip-all`).

Rollup of 6 pull requests

Successful merges:

 - #103023 (Adding `fuchsia-ignore` and `needs-unwind` to compiler test cases)
 - #103142 (Make diagnostic for unsatisfied `Termination` bounds more precise)
 - #103154 (Fix typo in `ReverseSearcher` docs)
 - #103159 (Remove the redundant `Some(try_opt!(..))` in `checked_pow`)
 - #103163 (Remove all uses of array_assume_init)
 - #103168 (Stabilize asm_sym)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

Stabilize asm_sym

Tracking issue #93333

Reference PR: https://github.com/rust-lang/reference/pull/1270

Remove all uses of array_assume_init

See https://github.com/rust-lang/rust/pull/103134#discussion_r997462733

r? `@scottmcm`

Remove the redundant `Some(try_opt!(..))` in `checked_pow`

The final return value doesn't need to be tried at all -- we can just
return the checked option directly. The optimizer can probably figure
this out anyway, but there's no need to make it work here.

Fix typo in `ReverseSearcher` docs

Make diagnostic for unsatisfied `Termination` bounds more precise

Don't blindly emit a diagnostic claiming that “*`main` has an invalid return type*” if we encounter a type that should but doesn't implement `std::process::Termination` and isn't actually the return type of the program entry `main`.

Fixes #103052.

``@rustbot`` label A-diagnostics T-compiler T-libs
r? diagnostics

Adding `fuchsia-ignore` and `needs-unwind` to compiler test cases

Final tests covering missing privileges

r? ``@tmandry``

cc. ``@djkoloski``

Support DirEntry metadata calls in miri

This should work as it uses lstat64 which is supported here: ~https://github.com/rust-lang/miri/blob/d9ad25ee4bbd9364c498959cdc82b5fa6c41e63c/src/shims/unix/macos/foreign_items.rs#L42~ just noticed that's macos, linux would be using statx: https://github.com/rust-lang/miri/blob/86f0e63b21721fe2c14608644f467b9cb21945eb/src/shims/unix/linux/foreign_items.rs#L112

The failing syscall is `dirfd`, so maybe that should actually be added to the shims?

⬆ rust-analyzer

r? `@ghost`

Remove `RunCompiler::emitter`.

It's no longer used.

r? `@bjorn3`

Since it's possible to have a 700.5px viewport width, the JS needs to not
switch to mobile mode in such a setup.

The two rules within it can and should be done without the separate
media query:

  * There ain't no rule saying a viewport can't be `700.5px` wide, since
    hardware pixels can be finer than CSS pixels.

  * The rule for the first example-wrap child should probably apply
    on mobile.

  * The rule for the source sidebar is overriden by the mobile rule
    setting `max-width: 100vw`, so it can be merged with the rest
    of the styles.

Remove "execute" bit from lock file permissions

Previously, flock would set the "execute" bit on Rust lock files. That makes no sense.

This patch clears the "execute" bit on Rust lock files.

See issue #102531.

Rollup of 4 pull requests

Successful merges:

 - #103152 (Use named arguments to make GUI test more clear)
 - #103160 (rustdoc: factor JS mobile scroll lock into its own function)
 - #103161 (rustdoc: remove redundant CSS on `#copy-path`)
 - #103162 (rustdoc: remove redundant CSS `#crate-search { border-radius }`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

It's no longer used.

rustdoc: remove redundant CSS `#crate-search { border-radius }`

This is the same border-radius that's always set on that ID:

https://github.com/rust-lang/rust/blob/a9d1cafa878ecc04a4aa7aaa7df0414a29a2bd0b/src/librustdoc/html/static/css/rustdoc.css#L825-L836

rustdoc: remove redundant CSS on `#copy-path`

The border and background were removed in 5d004c1e, but not all the CSS was.