name resolution for guard patterns
This PR provides an initial implementation of name resolution for guard patterns [(RFC 3637)](https://github.com/rust-lang/rfcs/blob/master/text/3637-guard-patterns.md). This does not change the requirement that the bindings on either side of an or-pattern must be the same [(proposal here)](https://github.com/rust-lang/rfcs/blob/master/text/3637-guard-patterns.md#allowing-mismatching-bindings-when-possible); the code that handles that is separate from what this PR touches, so I'm saving it for a follow-up.
On a technical level, this separates "collecting the bindings in a pattern" (which was already done for or-patterns) from "introducing those bindings into scope". I believe the approach used here can be extended straightforwardly in the future to work with `if let` guard patterns, but I haven't tried it myself since we don't allow those yet.
Tracking issue for guard patterns: #129967
cc ``@Nadrieril``
split `asm!` parsing and validation
This PR splits `asm!` parsing and validation into two separate steps.
The parser constructs a `Vec<RawAsmArg>`, with each element corresponding to an argument to one of the `asm!` macros.
The validation then checks things like ordering of arguments or that options are not provided twice.
The motivation is https://github.com/rust-lang/rust/issues/140279, which wants to add `#[cfg(...)]` support to these arguments. This support can now be added in a straightforward way by adding an `attributes: ast::AttrVec` field to `RawAsmArg`.
An extra reason for this split is that `rustfmt` probably wants to format the assembly at some point (currently that appears to be stubbed out, and the formatting is unstable https://github.com/rust-lang/style-team/issues/152).
r? ``@ghost`` (just want to look at CI for now)
cc ``@ytmimi`` we discussed asm formatting a little while ago in https://github.com/rust-lang/rustfmt/issues/6526. Am I correct in assuming that `AsmArgs` does not give enough information for formatting, but that `RawAsmArgs` would (it e.g. does not join information from multiple lines). This must have been an issue before?
try-job: aarch64-apple
Stabilize the avx512 target features
This PR stabilizes the AVX512 target features - see [this comment](https://github.com/rust-lang/rust/issues/111137#issuecomment-2745821279).
Tracking Issue - #44839
The target feature UI tests have been changed to `x87` (chosen because this is very unlikely to stablize ever, please comment if some other feature will be better)
related: #111137
[win][arm64] Remove 'Arm64 Hazard' undocumented MSVC option and instead disable problematic test
PR #140758 added the undocumented `/arm64hazardfree` MSVC linker flag to work around a test failure where LLVM generated code that would trip a hazard in an outdated ARM processor.
Adding this flag caused issues with LLD, as it doesn't recognize it.
Rethinking the issue, using the undocumented flag seems like the incorrect solution: there's no guarantee that the flag won't be removed in the future, or change its meaning.
Instead, I've disabled the problematic test for Arm64 Windows and have filed a bug with the MSVC team to have the check removed: <https://developercommunity.microsoft.com/t/Remove-checking-for-and-fixing-Cortex-A/10905134>
This PR supersedes #140977
r? ```@jieyouxu```
Remove #![feature(let_chains)] from library and src/librustdoc
PR https://github.com/rust-lang/rust/pull/132833 has stabilized the `let_chains` feature. This PR removes the last occurences from the library, the compiler, and librustdoc (also because #140887 missed the conditional in one of the crates as it was behind the "rustc" feature).
We keep `core` as exercise for the future as updating it is non-trivial (see PR thread).
check coroutines with `TypingMode::Borrowck` to avoid cyclic reasoning
MIR borrowck taints its output if an obligation fails. This could then cause `check_coroutine_obligations` to silence its error, causing us to not emit and actual error and ICE.
Fixes the ICE in https://github.com/rust-lang/trait-system-refactor-initiative/issues/199. It is unfortunately still a regression.
r? compiler-errors
MIR borrowck taints its output if an obligation fails. This could then cause
`check_coroutine_obligations` to silence its error, causing us to not emit
and actual error and ICE.
Rollup of 8 pull requests
Successful merges:
- #140208 (Make well-formedness predicates no longer coinductive)
- #140957 (Add `#[must_use]` to Array::map)
- #141031 (Async drop fix for dropee from another crate (#140858))
- #141036 (ci: split the dist-ohos job)
- #141051 (Remove some unnecessary erases)
- #141056 (Lowercase git url for rust-lang/enzyme.git)
- #141059 (HIR: explain in comment why `ExprKind::If` "then" is an `Expr`)
- #141070 (Do not emit help when shorthand from macro when suggest `?` or `expect`)
r? `@ghost`
`@rustbot` modify labels: rollup
Do not emit help when shorthand from macro when suggest `?` or `expect`
Fixes#140659
I didn't fully minimize the original bug, but I found a similar test case, and they have perhaps the same root cause. For the bug mentioned in #140659 , I also tested it locally and passed it.
Jieyou has worked on this part before, maybe r? `@jieyouxu`
Async drop fix for dropee from another crate (#140858)
Fixes https://github.com/rust-lang/rust/issues/140858.
For `AsyncDestructor` impl def id was wrongly kept as a LocalDefId, which causes crash when dropee is declared in another crate.
Also, potential problem found:
when user crate drops type with async drop in dependency crate, and user crate doesn't enable `feature(async_drop)`, then sync drop version will be used.
Is it a problem? Do we need some notification about such situations?
Make well-formedness predicates no longer coinductive
This PR makes well-formedness no longer coinductive. It was made coinductive in https://github.com/rust-lang/rust/pull/98542, but AFAICT this was only to fix UI tests since we stopped lowering `where Ty:` to an empty-region outlives predicate but to a WF predicate instead.
Arguably it should lower to something completely different, something like a "type mentioned no-op predicate", but well-formedness serves this purpose fine today, and since no code (according to crater) relies on this coinductive behavior, we'd like to avoid having to emulate it in the new solver.
Fixes#123456 (I didn't want to add a test since it seems low-value to have a ICE test for a fuzzer minimization that is basically garbage code.)
Fixes#109764 (not sure if this behavior is emulatable w/o coinductive WF?)
Fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/169
r? lcnr
Revert "Fix linking statics on Arm64EC #140176"
This reverts PR #140176.
Unfortunately, this will reopen https://github.com/rust-lang/rust/issues/138541 (re-breaking the `arm64ec-pc-windows-msvc` target).
Unfortunately, multiple people are [reporting linker warnings related to `__rust_no_alloc_shim_is_unstable`](https://github.com/rust-lang/rust/pull/140176#issuecomment-2879715554) after this change in `x86_64-pc-windows-msvc` as well. The solution isn't quite clear yet, let's revert to avoid the linker warnings on the Tier 1 MSVC target for now[^timing], and try a reland with a determined solution for `__rust_no_alloc_shim_is_unstable`.
Judging from [people reporting that they are observing this also when bootstrapping w/ stage0 rustc](https://github.com/rust-lang/rust/pull/140176#issuecomment-2881867433), we may have to cut a new beta and then repoint stage0 against that newer beta?
cc `@dpaoliello` `@wesleywiser`
r? `@wesleywiser` (or compiler)
[^timing]: Note that it's still RustWeek this week, so most team members are N/A.
Add negative test coverage for `-Clink-self-contained` and `-Zlinker-features`
Noticed while reviewing stabilization #140525 that we don't have any negative test coverage for these flags. Feel free to cherry-pick these tests into the stabilization PR, or we can land these before separately.
r? `@lqd`
Remove manual WF hack
We do not need this hack anymore since we fixed the candidate selection problems with `Sized` bounds. We prefer built-in sized bounds now since #138176, which fixes the only regression this hack was intended to fix.
While this theoretically is broken for some code, for example, when there a param-env bound that shadows an impl or built-in trait, we don't see it in practice and IMO it's not worth the burden of having to maintain this wart in `compare_method_predicate_entailment`.
The code that regresses is, for example:
```rust
trait Bar<'a> {}
trait Foo<'a, T> {
fn method(&self)
where
Self: Bar<'a>;
}
struct W<'a, T>(&'a T)
where
Self: Bar<'a>;
impl<'a, 'b, T> Bar<'a> for W<'b, T> {}
impl<'a, 'b, T> Foo<'a, T> for W<'b, T> {
fn method(&self) {}
}
```
Specifically, I don't believe this is really going to be encountered in practice. For this to fail, there must be a where clause in the *trait method* that would shadow an impl or built-in (non-`Sized`) candidate in the trait, and this shadowing would need to be encountered when solving a nested WF goal from the impl self type.
See #108544 for the original regression. Crater run is clean!
r? lcnr
Improve `dangerous_implicit_aurorefs` diagnostic output
This PR *greatly* improves the `dangerous_implicit_aurorefs` lint diagnostic output.
Kind of related to #140721.
r? ```@jieyouxu``` (maybe)
Use the new solver in the `impossible_predicates`
The old solver is unsound for many reasons. One of which was weaponized by `@lcnr` in #140212, where the old solver was incompletely considering a dyn vtable method to be impossible and replacing its vtable entry with a null value. This null function could be called post-mono.
The new solver is expected to be less incomplete due to its correct handling of higher-ranked aliases in relate. This PR switches the `impossible_predicates` query to use the new solver, which patches this UB.
r? lcnr
Unfortunately, multiple people are reporting linker warnings related to
`__rust_no_alloc_shim_is_unstable` after this change. The solution isn't
quite clear yet, let's revert to green for now, and try a reland with a
determined solution for `__rust_no_alloc_shim_is_unstable`.
This reverts commit c8b7f32434, reversing
changes made to 667247db71.
