Signed-off-by: David Wood <[email protected]>

…bilee

Box validity: update for new zero-sized rules

Fixes rust-lang/unsafe-code-guidelines#529

Cc `@joshlf` `@rust-lang/opsem`

…l, r=lcnr

Make decoding non-optional `LazyArray` panic if not set

Tables may be [defined](https://github.com/rust-lang/rust/blob/9649706eada1b2c68cf6504356efb058f68ad739/compiler/rustc_metadata/src/rmeta/mod.rs#L377) as `optional:` or `defaulted:`. If optional, if we try to read a value from a key that was never encoded, we should panic. This has high value in ensuring correctness over a defaulted table, so the tradeoff is worth considering, since it signals the compiler has a buggy encode impl, rather than just defaulting to a value.

HOWEVER, `optional:` arrays were side-stepping this. So this PR fixes that, and makes `optional:` tables of `LazyArray` act like `LazyValue`, and panic if it's not assigned a value during encoding.

During this PR, I found that `deduced_param_attrs` has buggy (?? i think??) implementation where it will refuse to encode cross-crate `deduced_param_attrs` unless we're codegening, we're optimizing the library, and incremental is disabled. This seems incredibly wrong, but I don't want to fix it in this PR.
https://github.com/rust-lang/rust/blob/9649706eada1b2c68cf6504356efb058f68ad739/compiler/rustc_metadata/src/rmeta/encoder.rs#L1733-L1747

compiler_fence documentation: emphasize synchronization, not reordering

Our `fence` docs have at some point been update to explain that they are about synchronization, not about "preventing reordering". This updates the `compiler_fence` docs n the same vein, mostly by referring to the `fence` docs.

The old docs make it sound like I can put a compiler_fence in the middle of a bunch of non-atomic operations and that would achieve any kind of guarantee. It does not, atomic operations are still required to do synchronization.

I also slightly tweaked the `fence` docs, to put the synchronization first and the "prevent reordering" second.

Cc `@rust-lang/opsem` `@chorman0773` `@m-ou-se`

Fixes rust-lang#129189
Fixes rust-lang#54962

Remove kobzol vacation status

Conflicts with rust-lang#129843, so should be merged after it.

…=compiler-errors,jieyouxu

chore: Fix typos in 'compiler' (batch 1)

Batch 1/3: Fixes typos in `compiler`

(See [issue](rust-lang#129874) tracking all PRs with typos fixes)

…=fee1-dead

chore: Fix typos in 'compiler' (batch 2)

Batch 2/3: Fixes typos in `compiler`

(See [issue](rust-lang#129874) tracking all PRs with typos fixes)

…=jieyouxu

chore: Fix typos in 'compiler' (batch 3)

Batch 3/3: Fixes typos in `compiler`

(See [issue](rust-lang#129874) tracking all PRs with typos fixes)

Remove stray word in a comment

…lfJung

Clarify language around ptrs in slice::raw

More specifically we explicitly mention that the pointer should be non-null as a top level requirement. Nullptrs are always valid for zero sized operations, so just validity (and alignment) does not guarantee non-nullness as implied in the existing docs.

We also explicitly call out ZSTs as an additional example where perhaps unintuitively alignment and non-nullness still have to hold.

Finally we change `data` in the range functions to `start`, which seems like a typo to me.

Touches docs for rust-lang#89792

r? RalfJung

…, r=lqd

mailmap: add new email for davidtwco

mailmapper?

I think I have done this right? lol

…apkin

Fix compile error in solid's remove_dir_all

Before this PR, `x check library/std --target=aarch64-kmc-solid_asp3` will fail with:
```
error[E0382]: use of partially moved value: `result`
   --> std/src/sys/pal/solid/fs.rs:544:20
    |
541 |         if let Err(err) = result
    |                    --- value partially moved here
...
544 |             return result;
    |                    ^^^^^^ value used here after partial move
    |
    = note: partial move occurs because value has type `io::error::Error`, which does not implement the `Copy` trait
help: borrow this binding in the pattern to avoid moving the value
    |
541 |         if let Err(ref err) = result
    |                    +++

```

cc `@kawadakk` I think this will clear up https://solid-rs.github.io/toolstate/ :)