Signed-off-by: xizheyin <[email protected]>

Currently the code continues, using an empty path, but it doesn't need
to.

`resolve_ident_in_lexical_scope` checks for an empty name. Why is this
necessary? Because `parse_item_impl` can produce an `impl` block with an
empty trait name in some cases. This is pretty gross and very
non-obvious.

This commit avoids the use of the empty trait name. In one case the
trait name is instead pulled from `TyKind::ImplTrait`, which prevents
the output for `tests/ui/impl-trait/extra-impl-in-trait-impl.rs` from
changing. In the other case we just fail the parse and don't try to
recover. I think losing error recovery in this obscure case is worth
the code cleanup.

This change affects `tests/ui/parser/impl-parsing.rs`, which is split in
two, and the obsolete `..` syntax cases are removed (they are tested
elsewhere).

Signed-off-by: xizheyin <[email protected]>

We should enable these to avoid misinterpreting uses of the extended
syntax as code blocks. This happens in practice with multi-paragraph
footnotes, as discovered in rust-lang#139064.

In `swap_nonoverlapping_short` there's a new `debug_assert!`, and if that's enabled then the `alloca`s don't optimize out.

Inspired by some of the communication issues around the stabilization of
`let`-chains, give more fine-grained information about the status of
updating style for any new syntax.

This does not change the process or blockers in any way; it only
*documents* the current state in the tracking issue. For instance, in
the case of `let`-chains, we would have checked the boxes for "Style
team decision" and "(non-blocking) Formatting has been implemented", and
not checked the box for the style guide. That would have then provided
better supporting information for any decisions.

Includes the following changes:

* Avoid OOB access in `memcpy` and `memmove` [1]
* Enable intrinsics on AVR [2]
* `libm` updates to avoid using `core::arch` vector intrinsics [3]

[1]: rust-lang/compiler-builtins#799
[2]: rust-lang/compiler-builtins#791
[3]: rust-lang/compiler-builtins#814

Ensure `swap_nonoverlapping` is really always untyped

This replaces rust-lang#134954, which was arguably overcomplicated.

## Fixes rust-lang#134713

Actually using the type passed to `ptr::swap_nonoverlapping` for anything other than its size + align turns out to not work, so this goes back to always erasing the types down to just bytes.

(Except in `const`, which keeps doing the same thing as before to preserve ``@RalfJung's`` fix from rust-lang#134689)

## Fixes rust-lang#134946

I'd previously moved the swapping to use auto-vectorization *on bytes*, but someone pointed out on Discord that the tail loop handling from that left a whole bunch of byte-by-byte swapping around.  This goes back to manual tail handling to avoid that, then still triggers auto-vectorization on pointer-width values.  (So you'll see `<4 x i64>` on `x86-64-v3` for example.)

…pper-improvement, r=camelid

Small code improvement in rustdoc hidden stripper

This is a very minor code improvement following rust-lang#137534. It doesn't change anything about the performance issue.

r? ``@notriddle``

…Gomez

Clean up librustdoc::html::render to be better encapsulated

Closes rust-lang#138567

Allow drivers to supply a list of extra symbols to intern

Allows adding new symbols as `const`s in external drivers, desirable in Clippy so we can use them in patterns to replace code like https://github.com/rust-lang/rust/blob/75530e9f72a1990ed2305e16fd51d02f47048f12/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs#L66

The Clippy change adds a couple symbols as a demo, the exact `clippy_utils` API and replacing other usages can be done on the Clippy side to minimise sync conflicts

Temporarily leave the review rotation

r? ghost

saethlin is back from vacation

rustdoc: Enable Markdown extensions when looking for doctests

Fixes rust-lang#139064.

We should enable these to avoid misinterpreting uses of the extended
syntax as code blocks. This happens in practice with multi-paragraph
footnotes, as discovered in rust-lang#139064.

…viscross

Tracking issue template: fine-grained information on style update status

Inspired by some of the communication issues around the stabilization of
`let`-chains, give more fine-grained information about the status of
updating style for any new syntax.

This does not change the process or blockers in any way; it only
*documents* the current state in the tracking issue. For instance, in
the case of `let`-chains, we would have checked the boxes for "Style
team decision" and "(non-blocking) Formatting has been implemented", and
not checked the box for the style guide. That would have then provided
better supporting information for any decisions.

Update `compiler-builtins` to 0.1.153

Includes the following changes:

* Avoid OOB access in `memcpy` and `memmove` [1]
* Enable intrinsics on AVR [2]
* `libm` updates to avoid using `core::arch` vector intrinsics [3]

[1]: rust-lang/compiler-builtins#799
[2]: rust-lang/compiler-builtins#791
[3]: rust-lang/compiler-builtins#814