Rename hir::ExprAgain to hir::ExprContinue
The current name is confusing and historical.
I also used this PR to clean up the annoying indentation in `check/mod.rs`. If that's viewed as too tangential a change, I'll split it up, but it seemed reasonable to slip it in to reduce @bors's work. It's easy to compare for the two commits individually.
r? @petrochenkov
async/await
This PR implements `async`/`await` syntax for `async fn` in Rust 2015 and `async` closures and `async` blocks in Rust 2018 (tracking issue: https://github.com/rust-lang/rust/issues/50547). Limitations: non-`move` async closures with arguments are currently not supported, nor are `async fn` with multiple different input lifetimes. These limitations are not fundamental and will be removed in the future, however I'd like to go ahead and get this PR merged so we can start experimenting with this in combination with futures 0.3.
Based on https://github.com/rust-lang/rust/pull/51414.
cc @petrochenkov for parsing changes.
r? @eddyb
Add label to lint for lifetimes used once
```
error: lifetime parameter `'a` only used once
--> $DIR/fn-types.rs:19:10
|
LL | a: for<'a> fn(&'a u32), //~ ERROR `'a` only used once
| ^^ -- ...is used only here
| |
| this lifetime...
```
Support future deprecation for rustc_deprecated
Follow-up to #49179 to allow `since` parameters to be set to future versions of Rust and correspondingly to not be treated as deprecated until that version. This is required for #30459 to be completed (though we'll need to wait until this hits beta).
yet another "old borrowck" bug around match default bindings
We were getting the type of the parameter from its pattern, but that didn't include adjustments. I did a `ripgrep` around and this seemed to be the only affected case.
The reason this didn't show up as an ICE earlier is that mem-categorization is lenient with respect to weird discrepancies. I am going to add more delay-span-bug calls shortly around that (I'll push onto the PR).
This example is an ICE, but I presume that there is a way to make a soundness example out of this -- it basically ignores borrows occuring inside match-default-bindings in a closure, though only if the implicit deref is at the top-level. It happens though that this occurs frequently in iterators, which often give a `&T` parameter.
Fixes#51415Fixes#49534
r? @eddyb
This is gated on edition 2018 & the `async_await` feature gate.
The parser will accept `async fn` and `async unsafe fn` as fn
items. Along the same lines as `const fn`, only `async unsafe fn`
is permitted, not `unsafe async fn`.The parser will not accept
`async` functions as trait methods.
To do a little code clean up, four fields of the function type
struct have been merged into the new `FnHeader` struct: constness,
asyncness, unsafety, and ABI.
Also, a small bug in HIR printing is fixed: it previously printed
`const unsafe fn` as `unsafe const fn`, which is grammatically
incorrect.
do not ICE when existing type info is incomplete
Apparently master is kinda ICE-y right now, but only for some people (sadly that set includes me).
I'm not crazy about this PR, because it seems to regress diagnostics a lot, but it *does* fix the problems. I think probably fixing the diagnostics should be done by doing a better job of suppressing errors?
Mitigates #51683
r? @oli-obk
The Great Generics Generalisation: HIR Edition
This is essentially a followup to https://github.com/rust-lang/rust/pull/45930, consolidating the use of separate lifetime and type vectors into single kinds vectors wherever possible. This is intended to provide more of the groundwork for const generics (https://github.com/rust-lang/rust/issues/44580).
r? @eddyb
cc @yodaldevoid