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 Hence I'm removing these outdated branches.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.
Refactor AST trait bound modifiers
Instead of having two types to represent trait bound modifiers in the parser / the AST (`parser::ty::BoundModifiers` & `ast::TraitBoundModifier`), only to map one to the other later, just use `parser::ty::BoundModifiers` (moved & renamed to `ast::TraitBoundModifiers`).
The struct type is more extensible and easier to deal with (see [here](https://github.com/rust-lang/rust/pull/119099/files#r1430749981) and [here](https://github.com/rust-lang/rust/pull/119099/files#r1430752116) for context) since it more closely models what it represents: A compound of two kinds of modifiers, constness and polarity. Modeling this as an enum (the now removed `ast::TraitBoundModifier`) meant one had to add a new variant per *combination* of modifier kind, which simply isn't scalable and which lead to a lot of explicit non-DRY matches.
NB: `hir::TraitBoundModifier` being an enum is fine since HIR doesn't need to worry representing invalid modifier kind combinations as those get rejected during AST validation thereby immensely cutting down the number of possibilities.
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
Rollup of 5 pull requests
Successful merges:
- #118729 (Add release notes for 1.75.0)
- #119124 (don't build `rust-analyzer-proc-macro-srv` on def config )
- #119154 (Simple modification of `non_lifetime_binders`'s diagnostic information to adapt to type binders)
- #119176 (Fix name error in aarch64_apple_watchos tier 3 target)
- #119182 (Update sysinfo version to 0.30.0)
r? `@ghost`
`@rustbot` modify labels: rollup
Fix name error in aarch64_apple_watchos tier 3 target
fix llvm_target wrong name `aarch-apple-watchos` to `aarch64-apple-watchos`, sorry for my mistake.
previous pr: https://github.com/rust-lang/rust/pull/119074
r? compiler-team
Simple modification of `non_lifetime_binders`'s diagnostic information to adapt to type binders
fixes#119067
Replace diagnostic information "lifetime bounds cannot be used in this context" to "bounds cannot be used in this context".
```rust
#![allow(incomplete_features)]
#![feature(non_lifetime_binders)]
trait Trait {}
trait Trait2
where for <T: Trait> ():{}
//~^ ERROR bounds cannot be used in this context
```
