Rollup of 26 pull requests
Successful merges:
- #56425 (Redo the docs for Vec::set_len)
- #56906 (Issue #56905)
- #57042 (Don't call `FieldPlacement::count` when count is too large)
- #57175 (Stabilize `let` bindings and destructuring in constants and const fn)
- #57192 (Change std::error::Error trait documentation to talk about `source` instead of `cause`)
- #57296 (Fixed the link to the ? operator)
- #57368 (Use CMAKE_{C,CXX}_COMPILER_LAUNCHER for ccache)
- #57400 (Rustdoc: update Source Serif Pro and replace Heuristica italic)
- #57417 (rustdoc: use text-based doctest parsing if a macro is wrapping main)
- #57433 (Add link destination for `read-ownership`)
- #57434 (Remove `CrateNum::Invalid`.)
- #57441 (Supporting backtrace for x86_64-fortanix-unknown-sgx.)
- #57450 (actually take a slice in this example)
- #57459 (Reference tracking issue for inherent associated types in diagnostic)
- #57463 (docs: Fix some 'second-edition' links)
- #57466 (Remove outdated comment)
- #57493 (use structured suggestion when casting a reference)
- #57498 (make note of one more normalization that Paths do)
- #57499 (note that FromStr does not work for borrowed types)
- #57505 (Remove submodule step from README)
- #57510 (Add a profiles section to the manifest)
- #57511 (Fix undefined behavior)
- #57519 (Correct RELEASES.md for 1.32.0)
- #57522 (don't unwrap unexpected tokens in `format!`)
- #57530 (Fixing a typographical error.)
- #57535 (Stabilise irrefutable if-let and while-let patterns)
Failed merges:
r? @ghost
Implement RFC 2338, "Type alias enum variants"
This PR implements [RFC 2338](https://github.com/rust-lang/rfcs/pull/2338), allowing one to write code like the following.
```rust
#![feature(type_alias_enum_variants)]
enum Foo {
Bar(i32),
Baz { i: i32 },
}
type Alias = Foo;
fn main() {
let t = Alias::Bar(0);
let t = Alias::Baz { i: 0 };
match t {
Alias::Bar(_i) => {}
Alias::Baz { i: _i } => {}
}
}
```
Since `Self` can be considered a type alias in this context, it also enables using `Self::Variant` as both a constructor and pattern.
Fixes issues #56199 and #56611.
N.B., after discussing the syntax for type arguments on enum variants with @petrochenkov and @eddyb (there are also a few comments on the [tracking issue](https://github.com/rust-lang/rust/issues/49683)), the consensus seems to be treat the syntax as follows, which ought to be backwards-compatible.
```rust
Option::<u8>::None; // OK
Option::None::<u8>; // OK, but lint in near future (hard error next edition?)
Alias::<u8>::None; // OK
Alias::None::<u8>; // Error
```
I do not know if this will need an FCP, but let's start one if so.
Fix stabilization version numbers (exhaustive_integer_patterns + macro_literal_matcher)
+ `exhaustive_integer_patterns` slipped 1.32; merged in 1.33 -- https://github.com/rust-lang/rust/pull/56362
+ `macro_literal_matcher` isn't stable on current stable (1.31) but is on beta (1.32).
r? @varkor
Stabilise exhaustive integer patterns
This is dependent on the FCP for https://github.com/rust-lang/rfcs/pull/2591 being completed, but that should happen tomorrow, so there's little harm in opening this PR early.
Closes#50907.
