Clarify the meaning of `AttributeOrder::KeepFirst` and `AttributeOrder::KeepLast`
Clarify the meaning of `KeepLast` and `KeepFirst` for https://github.com/rust-lang/rust/issues/131229#issuecomment-2971353197
Just a minor clarification, but me and ``@JonathanBrouwer`` have confused these two a few times so I think it's warranted.
r? ``@oli-obk``
cc ``@JonathanBrouwer``
setup typos check in CI
This allows to check typos in CI, currently for compiler only (to reduce commit size with fixes). With current setup, exclude list is quite short, so it worth trying?
Also includes commits with actual typo fixes.
MCP: https://github.com/rust-lang/compiler-team/issues/817
typos check currently turned for:
* ./compiler
* ./library
* ./src/bootstrap
* ./src/librustdoc
After merging, PRs which enables checks for other crates (tools) can be implemented too.
Found typos will **not break** other jobs immediately: (tests, building compiler for perf run). Job will be marked as red on completion in ~ 20 secs, so you will not forget to fix it whenever you want, before merging pr.
Check typos: `python x.py test tidy --extra-checks=spellcheck`
Apply typo fixes: `python x.py test tidy --extra-checks=spellcheck:fix` (in case if there only 1 suggestion of each typo)
Current fail in this pr is expected and shows how typo errors emitted. Commit with error will be removed after r+.
Attribute rework: a parser for single attributes without arguments
Part of rust-lang/rust#131229
r? `@jdonszelmann`
I think code (with comments) speaks for itself.
The only subtlety: now `#[cold]`, `#[no_mangle]`, & `#[track_caller]` do not get thrown away when malformed (i.e. have arguments). This doesn't matter too much (I think), because an error gets emitted either way, so the compilation will not finish.
Port `#[rustc_layout_scalar_valid_range_start/end]` to the new attrib…
Ports `rustc_layout_scalar_valid_range_start` and `rustc_layout_scalar_valid_range_end` to the new attribute parsing infrastructure for https://github.com/rust-lang/rust/issues/131229#issuecomment-2971353197
r? `@jdonszelmann`
Port `#[track_caller]` to the new attribute system
r? ``@oli-obk``
depends on https://github.com/rust-lang/rust/pull/142493Closesrust-lang/rust#142783
(didn't add a test for this, this situation should simply never come up again, the code was simply wrong. lmk if I should add it, but it won't test something very useful)
Add `#[loop_match]` for improved DFA codegen
tracking issue: https://github.com/rust-lang/rust/issues/132306
project goal: https://github.com/rust-lang/rust-project-goals/issues/258
This PR adds the `#[loop_match]` attribute, which aims to improve code generation for state machines. For some (very exciting) benchmarks, see https://github.com/rust-lang/rust-project-goals/issues/258#issuecomment-2732965199
Currently, a very restricted syntax pattern is accepted. We'd like to get feedback and merge this now before we go too far in a direction that others have concerns with.
## current state
We accept code that looks like this
```rust
#[loop_match]
loop {
state = 'blk: {
match state {
State::A => {
#[const_continue]
break 'blk State::B
}
State::B => { /* ... */ }
/* ... */
}
}
}
```
- a loop should have the same semantics with and without `#[loop_match]`: normal `continue` and `break` continue to work
- `#[const_continue]` is only allowed in loops annotated with `#[loop_match]`
- the loop body needs to have this particular shape (a single assignment to the match scrutinee, with the body a labelled block containing just a match)
## future work
- perform const evaluation on the `break` value
- support more state/scrutinee types
## maybe future work
- allow `continue 'label value` syntax, which `#[const_continue]` could then use.
- allow the match to be on an arbitrary expression (e.g. `State::Initial`)
- attempt to also optimize `break`/`continue` expressions that are not marked with `#[const_continue]`
r? ``@traviscross``
