If a label is placed on the block of a loop instead of the header, suggest moving it to the header.
Fixes#138585
If a label is placed on the block of a loop instead of the header, suggest to the user moving it to the loop header instead of ~~suggesting to remove it~~ emitting a tool-only suggestion to remove it.
```rs
fn main() {
loop 'a: { return; }
}
```
```diff
error: block label not supported here
--> src/main.rs:2:10
|
2 | loop 'a: { return; }
| ^^^ not supported here
+ |
+help: if you meant to label the loop, move this label before the loop
+ |
+2 - loop 'a: { return; }
+2 + 'a: loop { return; }
+ |
```
Questions for reviewer:
* The "desired output" in the linked issue had the main diagnostic be "misplaced loop label". Should the main diagnostic message the changed instead of leaving it as "block label not supported here"?
* Should this be `Applicability::MachineApplicable`?
mir_build: consider privacy when checking for irrefutable patterns
This PR fixes#137999.
Note that, since this makes the compiler reject code that was previously accepted, it will probably need a crater run.
I include a commit that factors out a common code pattern into a helper function, purely because the fact that this was repeated all over the place was bothering me. Let me know if I should split that into a separate PR instead.
Implement default methods for `io::Empty` and `io::Sink`
Implements default methods of `io::Read`, `io::BufRead`, and `io::Write` for `io::Empty` and `io::Sink`. These implementations are equivalent to the defaults, except in doing less unnecessary work.
`Read::read_to_string` and `BufRead::read_line` both have a redundant call to `str::from_utf8` which can't be inlined from `core` and `Write::write_all_vectored` has slicing logic which can't be simplified (See on [Compiler Explorer](https://rust.godbolt.org/z/KK6xcrWr4)). The rest are optimized to the minimal with `-C opt-level=3`, but this PR gives that benefit to unoptimized builds.
This includes an implementation of `Write::write_fmt` which just ignores the `fmt::Arguments<'_>`. This could be problematic whenever a user formatting impl is impure, but the docs do not guarantee that the args will be expanded.
Tracked in https://github.com/rust-lang/rust/issues/136756.
r? `@m-ou-se`
`MaybeUninit` inherent slice methods part 2
These were moved out of #129259 since they require additional libs-api approval. Tracking issue: #117428.
New API surface:
```rust
impl<T> [MaybeUninit<T>] {
// replacing fill; renamed to avoid conflict
pub fn write_filled(&mut self, value: T) -> &mut [T] where T: Clone;
// replacing fill_with; renamed to avoid conflict
pub fn write_with<F>(&mut self, value: F) -> &mut [T] where F: FnMut() -> T;
// renamed to remove "fill" terminology, since this is closer to the write_*_of_slice methods
pub fn write_iter<I>(&mut self, iter: I) -> (&mut [T], &mut Self) where I: Iterator<Item = T>;
}
```
Relevant motivation for these methods; see #129259 for earlier methods' motiviations.
* I chose `write_filled` since `filled` is being used as an object here, whereas it's being used as an action in `fill`.
* I chose `write_with` instead of `write_filled_with` since it's shorter and still matches well.
* I chose `write_iter` because it feels completely different from the fill methods, and still has the intent clear.
In all of the methods, it felt appropriate to ensure that they contained `write` to clarify that they are effectively just special ways of doing `MaybeUninit::write` for each element of a slice.
Tracking issue: https://github.com/rust-lang/rust/issues/117428
r? libs-api
Represent diagnostic side effects as dep nodes
This changes diagnostic to be tracked as a special dep node (`SideEffect`) instead of having a list of side effects associated with each dep node. `SideEffect` is always red and when forced, it emits the diagnostic and marks itself green. Each emitted diagnostic generates a new `SideEffect` with an unique dep node index.
Some implications of this:
- Diagnostic may now be emitted more than once as they can be emitted once when the `SideEffect` gets marked green and again if the task it depends on needs to be re-executed due to another node being red. It relies on deduplicating of diagnostics to avoid that.
- Anon tasks which emits diagnostics will no longer *incorrectly* be merged with other anon tasks.
- Reusing a CGU will now emit diagnostics from the task generating it.
fixes#13964
The lint `option_map_unwrap_or` used to have a similar issue in #10579,
so I borrowed its solution to fix this one.
changelog: [`option_if_let_else`]: fix FP when value partially moved
Parameter patterns are lowered to an `Ident` by
`lower_fn_params_to_names`, which is used when lowering bare function
types, trait methods, and foreign functions. Currently, there are two
exceptional cases where the lowered param can become an empty `Ident`.
- If the incoming pattern is an empty `Ident`. This occurs if the
parameter is anonymous, e.g. in a bare function type.
- If the incoming pattern is neither an ident nor an underscore. Any
such parameter will have triggered a compile error (hence the
`span_delayed_bug`), but lowering still occurs.
This commit replaces these empty `Ident` results with `None`, which
eliminates a number of `kw::Empty` uses, and makes it impossible to fail
to check for these exceptional cases.
Note: the `FIXME` comment in `is_unwrap_or_empty_symbol` is removed. It
actually should have been removed in #138482, the precursor to this PR.
That PR changed the lowering of wild patterns to `_` symbols instead of
empty symbols, which made the mentioned underscore check load-bearing.
Remove existing AFIDT implementation
This experiment will need to be reworked differently; I don't think we'll be going with the `dyn* Future` approach that is currently implemented.
r? oli-obk
Fixes#136286Fixes#137706Fixes#137895
Tracking:
* #133119
Revert: Add *_value methods to proc_macro lib
This reverts https://github.com/rust-lang/rust/pull/136355. That PR caused unexpected breakage:
- the rustc-dev component can no longer be loaded by cargo, which impacts Miri and clippy and likely others
- rustc_lexer can no longer be published to crates.io, which impacts RA
See https://github.com/rust-lang/rust/issues/138647 for context.
Cc `@GuillaumeGomez` `@Amanieu`
coverage: Don't store a body span in `FunctionCoverageInfo`
We aren't using this body span for anything truly essential, and having it around will be awkward when we eventually start to support expansion regions, since they aren't necessarily within the main body.
Remove double nesting in post-merge workflow
See [this](https://github.com/rust-lang/rust/pull/138630#issuecomment-2732224491) :)
Can be tested with:
```bash
#!/bin/bash
PARENT_COMMIT=493c38ba371929579fe136df26eccd9516347c7a
SHA=259fdb521200c9abba547302fc2c826479ef26b2
printf "<details>\n<summary>What is this?</summary>\n" >> output.log
printf "This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.\n" >> output.log
printf "</details>\n\n" >> output.log
cargo run --release post-merge-report ${PARENT_COMMIT} ${SHA} >> output.log
```
I think that it's better to leave the notice in CI, to avoid generating it in citool, which can also be executed locally.
r? `@marcoieni`
Temporarily disable Fuchsia test job to unblock queue
See <https://rust-lang.zulipchat.com/#narrow/channel/242791-t-infra/topic/fuchsia.20failure/with/506637259> for efforts to fix the test job.
This PR temporarily disables the Fuchsia test job to unblock the queue, so that neither the Fuchsia maintainers nor T-infra maintainers should feel pressured to fix the job ASAP.
Please feel free to re-enable once the test job is fixed.
FYI `@erickt` since you or other Fuchsia maintainers will need to revert this change to merge Fuchsia test job fixes in the future.
r? infra-ci
rust-lang/rust@23032f31c9 accidentally introduced some nondeterminism
in the ordering of lib.rmeta files, which we caught in our bazel-based
builds only recently due to being further behind than normal. In my
testing, this fixes the issue.
