This is a [breaking-change]: according to RFC #1445, constants used as
patterns must be of a type that *derives* `Eq`. If you encounter a
problem, you are most likely using a constant in an expression where the
type of the constant is some struct that does not currently implement
`Eq`. Something like the following:
```rust
struct SomeType { ... }
const SOME_CONST: SomeType = ...;
match foo {
SOME_CONST => ...
}
```
The easiest and most future compatible fix is to annotate the type in
question with `#[derive(Eq)]` (note that merely *implementing* `Eq` is
not enough, it must be *derived*):
```rust
struct SomeType { ... }
const SOME_CONST: SomeType = ...;
match foo {
SOME_CONST => ...
}
```
Another good option is to rewrite the match arm to use an `if`
condition (this is also particularly good for floating point types,
which implement `PartialEq` but not `Eq`):
```rust
match foo {
c if c == SOME_CONST => ...
}
```
Finally, a third alternative is to tag the type with
`#[structural_match]`; but this is not recommended, as the attribute is
never expected to be stabilized. Please see RFC #1445 for more details.
Remove `ErasedRegions` from substs
This commit removes the `ErasedRegions` enum from `Substs`. Instead, in trans, we just generate a vector of `ReStatic` of suitable length. The goal is both general cleanup and to help pave the way for a glorious future where erasure is used in type check.
r? @eddyb
One concern: might be nice to do some profiling. Not sure the best way to do that. Perhaps I'll investigate running nrc's test suite locally.
This hack has long since outlived its usefulness; the transition to
trans passing around full substitutions is basically done. Instead of
`ErasedRegions`, just supply substitutions with a suitable number of
`'static` entries, and invoke `erase_regions` when needed (the latter of
which we already do).
Make warnings of renamed and removed lints themselves lints
This adds the `renamed_and_removed_lints` warning, defaulting
to the warning level.
Fixes#31141
Docs: Change "statements" to "expressions" on `match`
I apt to use `expressions` over `statements`, because `match` is a expression in essence, though it can become a statement when followed a semicolon.
Annotate run-pass/backtrace with #[rustc_no_mir] on MSVC.
Fixes#32384 by not using MIR on MSVC for the functions in the path of the backtrace.
This is the known blocker for the MSVC MIR builder, hopefully the only one overall.
r? @alexcrichton Confirmed to work on a nightly, by @retep998.
rustdoc: Consider `doc(no_inline)` in crate-local inlining
Imports with `doc(no_inline)` will not be inlined, even when `doc(inline)` is present.
fixes#32343
r? @alexcrichton
Simplifying some of the phrasing explaining lifetime elision
Just simplifying some of the language expressing what kind of inference Rust can and can't do on function signatures.
Fix const trans
Fix#30615.
The idea was that when there are N autoderefs, first do N-1 derefs and check for autoref. If there is autoref, done, if not, do one more deref. But when N is zero, doing one more deref is wrong.
std: Store flowinfo/scope_id in host byte order
Apparently these aren't supposed to be stored in network byte order, so doing so
ends up causing failures when it would otherwise succeed when stored in the host
byte order.
Closes#32424
convert 99.9% of `try!`s to `?`s
The first commit is an automated conversion using the [untry] tool and the following command:
```
$ find -name '*.rs' -type f | xargs untry
```
at the root of the Rust repo.
[untry]: https://github.com/japaric/untry
cc @rust-lang/lang @alexcrichton @brson
Introduce 'cargotest' and the check-cargotest buildstep
This is a new suite of tests that verifies that the compiler builds specific revisions of select crates from crates.io.
It does not run by default. It is intended that bors runs these tests against all PRs, and gates on them. In this way we will make it harder still to break important swaths of the ecosystem, even on nightly.
This is a very basic implementation intended for feedback. The biggest thing it probably should do but doesn't is use a lockfile for every project it builds.
r? @alexcrichton cc @rust-lang/lang @rust-lang/libs
Niko Matsakis