Lots of vectors of messages called `message` or `msg`. This commit
pluralizes them.
Note that `emit_message_default` and `emit_messages_default` both
already existed, and both process a vector, so I renamed the former
`emit_messages_default_inner` because it's called by the latter.
`DiagCtxt::span_bug` is different to the other `DiagCtxt::span_*`
methods. This commit makes it the same, which requires changing
`DiagCtxt::span_delayed_bug` to not do everything within the
`inner.borrow_mut()`.
- Take a `Vec` instead of an iterator, because that's all that is
needed.
- Do an early return for the "no bugs" case.
- Use `enumerate` and an `i == 0` test to identify the first bug.
Those changes mean the `no_bug` variable can be removed, which I found
hard to read.
`IntoDiagnostic` defaults to `ErrorGuaranteed`, because errors are the
most common diagnostic level. It makes sense to do likewise for the
closely-related (and much more widely used) `DiagnosticBuilder` type,
letting us write `DiagnosticBuilder<'a, ErrorGuaranteed>` as just
`DiagnosticBuilder<'a>`. This cuts over 200 lines of code due to many
multi-line things becoming single line things.
We can just get the error level in the `match` and then use
`DiagnosticBuilder::new`. This then means a number of `DiagCtxt`
functions are no longer needed, because this was the one place that used
them.
Note: the commit changes the treatment of spans for `Expect`, which was
different to all the other cases, but this has no apparent effect.
Rollup of 5 pull requests
Successful merges:
- #117601 (Add support for hexagon-unknown-none-elf as target)
- #119169 (Rid the AST & HIR pretty printer of cruft)
- #119194 (Run fuchsia tests only on nightly)
- #119201 (tests: fix overaligned-constant to not over-specify getelementptr instr)
- #119215 (Emits error if has bound regions)
r? `@ghost`
`@rustbot` modify labels: rollup
tests: fix overaligned-constant to not over-specify getelementptr instr
On LLVM 18 we get slightly different arguments here, so it's easier to just regex those away. The important details are all still asserted as I understand things.
Fixes#119193.
`@rustbot` label: +llvm-main
Run fuchsia tests only on nightly
We discovered in https://github.com/rust-lang/rust/pull/119187 that the Fuchsia tests only work on nightly, and so we cannot have the `x86_64-gnu-integration` job run on beta and stable. This PR gates the job to only run in the nightly channel.
r? `@tmandry`
Rid the AST & HIR pretty printer of cruft
Found while working on #119163.
For `trait Trait: ?Sized {}` (semantically malformed), we currently output `trait Trait for ? Sized {}` (sic!) / `trait Trait for ? Sized { }` (sic!) if `-Zunpretty=expanded` / `-Zunpretty=hir` is passed.
`trait Tr for Sized? {}` (#15521) and later also `trait Tr for ?Sized {}` (I guess, #20194) is former Rust syntax. Hence I'm removing these outdated branches.
~~This will conflict with #119163, therefore marking this PR as blocked.~~ Rebased
Add support for `for await` loops
This adds support for `for await` loops. This includes parsing, desugaring in AST->HIR lowering, and adding some support functions to the library.
Given a loop like:
```rust
for await i in iter {
...
}
```
this is desugared to something like:
```rust
let mut iter = iter.into_async_iter();
while let Some(i) = loop {
match core::pin::Pin::new(&mut iter).poll_next(cx) {
Poll::Ready(i) => break i,
Poll::Pending => yield,
}
} {
...
}
```
This PR also adds a basic `IntoAsyncIterator` trait. This is partly for symmetry with the way `Iterator` and `IntoIterator` work. The other reason is that for async iterators it's helpful to have a place apart from the data structure being iterated over to store state. `IntoAsyncIterator` gives us a good place to do this.
I've gated this feature behind `async_for_loop` and opened #118898 as the feature tracking issue.
r? `@compiler-errors`
Exhaustiveness: reveal opaque types properly
Previously, exhaustiveness had no clear policy around opaque types. In this PR I propose the following policy: within the body of an item that defines the hidden type of some opaque type, exhaustiveness checking on a value of that opaque type is performed using the concrete hidden type inferred in this body.
I'm not sure how consistent this is with other operations allowed on opaque types; I believe this will require FCP.
From what I can tell, this doesn't change anything for non-empty types.
The observable changes are:
- when the real type is uninhabited, matches within the defining scopes can now rely on that for exhaustiveness, e.g.:
```rust
#[derive(Copy, Clone)]
enum Void {}
fn return_never_rpit(x: Void) -> impl Copy {
if false {
match return_never_rpit(x) {}
}
x
}
```
- this properly fixes ICEs like https://github.com/rust-lang/rust/issues/117100 that occurred because a same match could have some patterns where the type is revealed and some where it is not.
Bonus subtle point: if `x` is opaque, a match like `match x { ("", "") => {} ... }` will constrain its type ([playground](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2021&gist=901d715330eac40339b4016ac566d6c3)). This is not the case for `match x {}`: this will not constain the type, and will only compile if something else constrains the type to be empty.
Fixes https://github.com/rust-lang/rust/issues/117100
r? `@oli-obk`
Edited for precision of the wording
[Included](https://github.com/rust-lang/rust/pull/116821#issuecomment-1813171764) in the FCP on this PR is this rule:
> Within the body of an item that defines the hidden type of some opaque type, exhaustiveness checking on a value of that opaque type is performed using the concrete hidden type inferred in this body.
