fix: Skip match exhaustiveness checking if pattern type contains errors
Should fix https://github.com/rust-lang/rust-analyzer/issues/17509, checking when errors are involved is generally a bad idea as the algorithm doesn't really expect error types in the first place I believe
Check alias args for WF even if they have escaping bound vars
#### What
This PR stops skipping arguments of aliases if they have escaping bound vars, instead recursing into them and only discarding the resulting obligations referencing bounds vars.
#### An example:
From the test:
```
trait Trait {
type Gat<U: ?Sized>;
}
fn test<T>(f: for<'a> fn(<&'a T as Trait>::Gat<&'a [str]>)) where for<'a> &'a T: Trait {}
//~^ ERROR the size for values of type `[()]` cannot be known at compilation time
fn main() {}
```
We now prove that `str: Sized` in order for `&'a [str]` to be well-formed. We were previously unconditionally skipping over `&'a [str]` as it referenced a buond variable. We now recurse into it and instead only discard the `[str]: 'a` obligation because of the escaping bound vars.
#### Why?
This is a change that improves consistency about proving well-formedness earlier in the pipeline, which is necessary for future work on where-bounds in binders and correctly handling higher-ranked implied bounds. I don't expect this to fix any unsoundness.
#### What doesn't it fix?
Specifically, this doesn't check projection predicates' components are well-formed, because there are too many regressions: https://github.com/rust-lang/rust/pull/123737#issuecomment-2052198478
Bootstrap: Try renaming the file if removing fails
Second attempt at working around https://github.com/rust-lang/rust/issues/127126
If we can't remove the file, then try renaming it. This will leave the destination path free to use.
try-job: x86_64-msvc-ext
Use the symbol_name query instead of trying to infer from the link_name attribute
This prevents the calculated name from going out of sync with exported_symbols. It also avoids having to special case the panic_impl lang item.
It also makes it easier to fix miri with https://github.com/rust-lang/rust/pull/127173.
do not normalize `use foo::{self}` to `use foo`
It changes behaviour and can cause collisions. E.g. for the following snippet
```rs
mod foo {
pub mod bar {}
pub const bar: i32 = 8;
}
// transforming the below to `use foo::bar;` causes the error:
//
// the name `bar` is defined multiple times
use foo::bar::{self};
const bar: u32 = 99;
fn main() {
let local_bar = bar;
}
```
we still normalize
```rs
use foo::bar;
use foo::bar::{self};
```
to `use foo::bar;` because this cannot cause collisions.
See: https://github.com/rust-lang/rust-analyzer/pull/17140#issuecomment-2079189725
Automatically taint InferCtxt when errors are emitted
r? `@nnethercote`
Basically `InferCtxt::dcx` now returns a `DiagCtxt` that refers back to the `Cell<Option<ErrorGuaranteed>>` of the `InferCtxt` and thus when invoking `Diag::emit`, and the diagnostic is an error, we taint the `InferCtxt` directly.
That change on its own has no effect at all, because `InferCtxt` already tracks whether errors have been emitted by recording the global error count when it gets opened, and checking at the end whether the count changed. So I removed that error count check, which had a bit of fallout that I immediately fixed by invoking `InferCtxt::dcx` instead of `TyCtxt::dcx` in a bunch of places.
The remaining new errors are because an error was reported in another query, and never bubbled up. I think they are minor enough for this to be ok, and sometimes it actually improves diagnostics, by not silencing useful diagnostics anymore.
fixes#126485 (cc `@olafes)`
There are more improvements we can do (like tainting in hir ty lowering), but I would rather do that in follow up PRs, because it requires some refactorings.
Make `feature(effects)` require `-Znext-solver`
Per https://github.com/rust-lang/rust/pull/120639#pullrequestreview-2144804638
I made this a hard error because otherwise it should be a lint and that seemed more complicated. Not sure if this is the best place to put the error though.
r? project-const-traits
Cleanup bootstrap check-cfg
This PR cleanup many custom `check-cfg` in bootstrap that have been accumulated over the years.
As well as updating some outdated comments.
Add a regression test for #123630Fixes#123630
compiler should not suggest nonsensical signatures, original suggestion was
```
error[E0308]: mismatched types
--> src/lib.rs:3:31
|
3 | fn select<F, I>(filter: F) -> Select<F, I> {
| ------ ^^^^^^^^^^^^ expected `Select<F, I>`, found `()`
| |
| implicitly returns `()` as its body has no tail or `return` expression
|
= note: expected struct `Select<F, I>`
found unit type `()`
error[E0282]: type annotations needed for `Select<{closure@src/lib.rs:8:22: 8:25}, I>`
--> src/lib.rs:8:9
|
8 | let lit = select(|x| match x {
| ^^^
|
help: consider giving `lit` an explicit type, where the type for type parameter `I` is specified
|
8 | let lit: Select<{closure@src/lib.rs:8:22: 8:25}, I> = select(|x| match x {
| ++++++++++++++++++++++++++++++++++++++++++++
Some errors have detailed explanations: E0282, E0308. For more information about an error, try `rustc --explain E0282`.
```
coverage: Avoid getting extra unexpansion info when we don't need it
Several callers of `unexpand_into_body_span_with_visible_macro` would immediately discard the additional macro-related information, which is wasteful. We can avoid this by having them instead call a simpler method that just returns the span they care about.
This PR also moves the relevant functions out of `coverage::spans::from_mir` and into a new submodule `coverage::unexpand`, so that calling them from `coverage::mappings` is less awkward.
There should be no actual changes to coverage-instrumentation output, as demonstrated by the absence of test updates.
small correction to fmt::Pointer impl
~~The `addr` method does not require `T: Sized`, and is preferred for use over `expose_provenance`.~~
`expose_provenance` does not require `T: Sized`.
Update the LoongArch target documentation
The docs for the LoongArch targets are a bit dated since their introduction, and the prose has some room for improvement as well. Streamline a bit, referring to the neighboring targets' docs, and provide up-to-date information as much as I can come up with.
cc fellow target maintainer `@heiher` for review of target-specific bits
Replace some magic booleans in match-lowering with enums
This PR takes some boolean arguments used by the match-lowering code, and replaces them with dedicated enums that more clearly express their effect, while also making it much easier to find how each value is ultimately used.
Remove the `box_pointers` lint.
As the comment says, this lint "is mostly historical, and not particularly useful". It's not worth keeping it around.
r? ``@estebank``
