refactor check_{lang,library}_ub: use a single intrinsic
This enacts the plan I laid out [here](https://github.com/rust-lang/rust/pull/122282#issuecomment-1996917998): use a single intrinsic, called `ub_checks` (in aniticpation of https://github.com/rust-lang/compiler-team/issues/725), that just exposes the value of `debug_assertions` (consistently implemented in both codegen and the interpreter). Put the language vs library UB logic into the library.
This makes it easier to do something like https://github.com/rust-lang/rust/pull/122282 in the future: that just slightly alters the semantics of `ub_checks` (making it more approximating when crates built with different flags are mixed), but it no longer affects whether these checks can happen in Miri or compile-time.
The first commit just moves things around; I don't think these macros and functions belong into `intrinsics.rs` as they are not intrinsics.
r? `@saethlin`
Rename `hir::Local` into `hir::LetStmt`
Follow-up of #122776.
As discussed on [zulip](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/Improve.20naming.20of.20.60ExprKind.3A.3ALet.60.3F).
I made this change into a separate PR because I'm less sure about this change as is. For example, we have `visit_local` and `LocalSource` items. Is it fine to keep these two as is (I supposed it is but I prefer to ask) or not? Having `Node::Local(LetStmt)` makes things more explicit but is it going too far?
r? ```@oli-obk```
`useless_asref`: do not lint `.as_ref().map(Arc::clone)`
This applies to `Arc`, `Rc`, and their weak variants. Using `.clone()` would be less idiomatic.
This follows the discussion in <https://github.com/rust-lang/rust-clippy/issues/12528#issuecomment-2014444305>.
changelog: [`useless_asref`]: do not lint `.as_ref().map(Arc::clone)` and similar
don't lint [`mixed_attributes_style`] when mixing docs and other attrs
fixes: #12435fixes: #12436fixes: #12530
---
changelog: don't lint [`mixed_attributes_style`] when mixing different kind of attrs; and move it to late pass;
don't lint [`mixed_attributes_style`] when mixing docs and other attrs
add test files for issue #12436
move [`mixed_attributes_style`] to `LateLintPass` to enable global `allow`
stop [`mixed_attributes_style`] from linting on different attributes
add `@compile-flags` to [`mixed_attributes_style`]'s test;
turns out not linting in test mod is not a FN.
Apply suggestions from code review
Co-authored-by: Timo <30553356+y21@users.noreply.github.com>
move [`mixed_attributes_style`] to late pass and stop it from linting on different kind of attributes
Rollup of 8 pull requests
Successful merges:
- #114009 (compiler: allow transmute of ZST arrays with generics)
- #122195 (Note that the caller chooses a type for type param)
- #122651 (Suggest `_` for missing generic arguments in turbofish)
- #122784 (Add `tag_for_variant` query)
- #122839 (Split out `PredicatePolarity` from `ImplPolarity`)
- #122873 (Merge my contributor emails into one using mailmap)
- #122885 (Adjust better spastorino membership to triagebot's adhoc_groups)
- #122888 (add a couple more tests)
r? `@ghost`
`@rustbot` modify labels: rollup
Split out `PredicatePolarity` from `ImplPolarity`
Because having to deal with a third `Reservation` level in all the trait solver code is kind of weird.
r? `@lcnr` or `@oli-obk`
Note that the caller chooses a type for type param
```
error[E0308]: mismatched types
--> $DIR/return-impl-trait.rs:23:5
|
LL | fn other_bounds<T>() -> T
| - -
| | |
| | expected `T` because of return type
| | help: consider using an impl return type: `impl Trait`
| expected this type parameter
...
LL | ()
| ^^ expected type parameter `T`, found `()`
|
= note: expected type parameter `T`
found unit type `()`
= note: the caller chooses the type of T which can be different from ()
```
Tried to see if "expected this type parameter" can be replaced, but that goes all the way to `rustc_infer` so seems not worth the effort and can affect other diagnostics.
Revives #112088 and #104755.
Do not warn on .map(_::clone) for Arc, Rc, and their weak variants
Those constructions are idiomatic, and using `Arc::clone(x)` and `Rc::clone(x)` is often the recommended way of cloning a `Arc` or a `Rc`.
Fix#12528
changelog: [`map_clone`]: do not warn on `.map(_::clone)` for `Arc`, `Rc`, and their `Weak` variants
Fix infinite loop in `cast_sign_loss` when peeling unwrap method calls
Fixes#12506
The lint wants to peel method calls but didn't actually reassign the expression, leading to an infinite loop.
----
changelog: Fix infinite loop in [`cast_sign_loss`] when having two chained `.unwrap()` calls
Mention `size_hint()` effect in `flat_map_option` lint documentation.
The previous documentation for `flat_map_option` mentioned only readability benefits, but there is also at least one performance benefit: the `size_hint()` upper bound is preserved, whereas `flat_map().size_hint()` is always `(0, None)`.
Program demonstrating this difference:
```rust
fn main() {
let evens = |i| if i % 2 == 0 { Some(i) } else { None };
dbg!(
[1, 2, 3].iter().flat_map(evens).size_hint(),
[1, 2, 3].iter().filter_map(evens).size_hint(),
);
}
```
changelog: [`flat_map_option`]: Mention the benefit to `size_hint()`.
Experimental feature postfix match
This has a basic experimental implementation for the RFC postfix match (rust-lang/rfcs#3295, #121618). [Liaison is](https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/Postfix.20Match.20Liaison/near/423301844) ```@scottmcm``` with the lang team's [experimental feature gate process](https://github.com/rust-lang/lang-team/blob/master/src/how_to/experiment.md).
This feature has had an RFC for a while, and there has been discussion on it for a while. It would probably be valuable to see it out in the field rather than continue discussing it. This feature also allows to see how popular postfix expressions like this are for the postfix macros RFC, as those will take more time to implement.
It is entirely implemented in the parser, so it should be relatively easy to remove if needed.
This PR is split in to 5 commits to ease review.
1. The implementation of the feature & gating.
2. Add a MatchKind field, fix uses, fix pretty.
3. Basic rustfmt impl, as rustfmt crashes upon seeing this syntax without a fix.
4. Add new MatchSource to HIR for Clippy & other HIR consumers
Several (doc) comments were super outdated or didn't provide enough context.
Some doc comments shoved everything in a single paragraph without respecting
the fact that the first paragraph should be a single sentence because rustdoc
treats these as item descriptions / synopses on module pages.
Fix documentation typo "appects" > "affects"
changelog: none
This fixes a typo in the `iter_filter_is_some` and `iter_filter_is_ok` lint documentation.
