Account for `!` arm in tail `match` expr
On functions with a default return type that influences the coerced type of `match` arms, check if the failing arm is actually of type `!`. If so, suggest changing the return type so the coercion against the prior arms is successful.
```
error[E0308]: `match` arms have incompatible types
--> $DIR/match-tail-expr-never-type-error.rs:9:13
|
LL | fn bar(a: bool) {
| - help: try adding a return type: `-> i32`
LL | / match a {
LL | | true => 1,
| | - this is found to be of type `{integer}`
LL | | false => {
LL | | never()
| | ^^^^^^^
| | |
| | expected integer, found `()`
| | this expression is of type `!`, but it get's coerced to `()` due to its surrounding expression
LL | | }
LL | | }
| |_____- `match` arms have incompatible types
```
Fix#24157.
Allow setting `rla` labels via `rustbot`
https://github.com/rust-lang/rust-log-analyzer/pull/75 adds a `rla-silenced` label flag that will turn off RLA updates for non-bors tests. Allow setting that labels and others via `rustbot`.
- Rename them both `as_str`, which is the typical name for a function
that returns a `&str`. (`to_string` is appropriate for functions
returning `String` or maybe `Cow<'a, str>`.)
- Change `UnOp::as_str` from an associated function (weird!) to a
method.
- Avoid needless `self` dereferences.
- Rename them both `as_str`, which is the typical name for a function
that returns a `&str`. (`to_string` is appropriate for functions
returning `String` or maybe `Cow<'a, str>`.)
- Change `UnOp::as_str` from an associated function (weird!) to a
method.
- Avoid needless `self` dereferences.
Don't suggest `a.mul_add(b, c)` if parameters are not float
clippy::suboptimal_flops used to not check if the second parameter to f32/f64.mul_add() was float. Since the method is only defined to take `Self` as parameters, the suggestion was wrong.
Fixes#11831
changelog: [`suboptimal_float`]: Don't suggest `a.mul_add(b, c)` if parameters are not f32/f64
[`ptr_arg`]: recognize methods that also exist on slices
Fixes#11816
Not a new lint, just a very small improvement to the existing `ptr_arg` lint which would have caught the linked issue.
The problem was that the lint checks if a `Vec`-specific method was called, that is, if the receiver is `Vec<_>`.
This is the case for `len` and `is_empty`, however these methods also exist on slices so we can still lint there.
This logic exists in a different lint, so we can just reuse that here.
Interestingly, there was even a comment up top that explained what it should have been doing, but the logic for it just wasn't there?
changelog: [`ptr_arg`]: recognize methods that also exist on slices
<sub>Also, this is my 100th PR to clippy 🎉 </sub>
`manual_try_fold`: check that `fold` is really `Iterator::fold`
Fix#11876
changelog: [`manual_try_fold`]: suggest using `try_fold` only for `Iterator::fold` uses
Do not erase late bound regions when selecting inherent associated types
In the fix for #97156 we would want the following code:
```rust
#![feature(inherent_associated_types)]
#![allow(incomplete_features)]
struct Foo<T>(T);
impl Foo<fn(&'static ())> {
type Assoc = u32;
}
trait Other {}
impl Other for u32 {}
// FIXME(inherent_associated_types): Avoid emitting two diagnostics (they only differ in span).
// FIXME(inherent_associated_types): Enhancement: Spruce up the diagnostic by saying something like
// "implementation is not general enough" as is done for traits via
// `try_report_trait_placeholder_mismatch`.
fn bar(_: Foo<for<'a> fn(&'a ())>::Assoc) {}
//~^ ERROR mismatched types
//~| ERROR mismatched types
fn main() {}
```
to fail with ...
```
error[E0220]: associated type `Assoc` not found for `Foo<for<'a> fn(&'a ())>` in the current scope
--> tests/ui/associated-inherent-types/issue-109789.rs:18:36
|
4 | struct Foo<T>(T);
| ------------- associated item `Assoc` not found for this struct
...
18 | fn bar(_: Foo<for<'a> fn(&'a ())>::Assoc) {}
| ^^^^^ associated item not found in `Foo<for<'a> fn(&'a ())>`
|
= note: the associated type was found for
- `Foo<fn(&'static ())>`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0220`.
```
This PR fixes the ICE we are currently getting "was a subtype of Foo<Binder(fn(&ReStatic ()), [])> during selection but now it is not"
Also fixes#112631
r? `@lcnr`
On functions with a default return type that influences the coerced type
of `match` arms, check if the failing arm is actually of type `!`. If
so, suggest changing the return type so the coercion against the prior
arms is successful.
```
error[E0308]: `match` arms have incompatible types
--> $DIR/match-tail-expr-never-type-error.rs:9:13
|
LL | fn bar(a: bool) {
| - help: try adding a return type: `-> i32`
LL | / match a {
LL | | true => 1,
| | - this is found to be of type `{integer}`
LL | | false => {
LL | | never()
| | ^^^^^^^
| | |
| | expected integer, found `()`
| | this expression is of type `!`, but it get's coerced to `()` due to its surrounding expression
LL | | }
LL | | }
| |_____- `match` arms have incompatible types
```
Fix#24157.
Rollup of 4 pull requests
Successful merges:
- #118095 (Enable the Arm Cortex-A53 errata mitigation on aarch64-unknown-none)
- #118340 (Use helper functions in `pretty.rs` instead of accessing the `Cell`s manually)
- #118358 (make const tests independent of std debug assertions)
- #118359 (Suggest swapping the order of `ref` and `box`)
r? `@ghost`
`@rustbot` modify labels: rollup
Suggest swapping the order of `ref` and `box`
It is not valid grammar to write `ref box <ident>` in patterns, but `box ref <ident>` is.
This patch adds a diagnostic to suggest swapping them, analogous to what we do for `mut let`.
make const tests independent of std debug assertions
Fixes some fallout from https://github.com/rust-lang/rust/pull/110303: `ignore-debug` is bad since it makes it very annoying to develop rustc with debug assertions enabled.
These tests do not really provide any interesting test coverage, we already got plenty of other tests that check that we detect invalid enums. So we can just remove them.
Enable the Arm Cortex-A53 errata mitigation on aarch64-unknown-none
Arm Cortex-A53 CPUs have an errata related to a specific sequence of instructions - errata number 843419 (https://documentation-service.arm.com/static/5fa29fddb209f547eebd361d). There is a mitigation that can be applied at link-time which detects the when sequence of instructions exists at a specific alignment. When detected, the linker re-writes those instructions and either changes an ADRP to an ADR, or bounces to a veneer to break the sequence.
The linker argument to enable the mitigation is "--fix-cortex-a53-843419", and this is supported by GNU ld and LLVM lld. The gcc argument to enable the flag is "-mfix-cortex-a53-843419".
Because the aarch64-unknown-none target uses rust-lld directly, this patch causes rustc to emit the "--fix-cortex-a53-843419" argument when calling the linker, just like aarch64-linux-gnu-gcc on Ubuntu 22.04 does.
Failure to enable this mitigation in the linker can cause the production of instruction sequences that do not execute correctly on Arm Cortex-A53.
bootstrap: Memoize the LLVM rebuild hash to avoid very slow `x check`
Recently I've encountered a massive regression in the performance of re-running `x check` after making no changes.
It used to take around 2 seconds, and now it takes 20-30 seconds. That's quite a hassle when r-a runs it every time I save.
After some poking around, what I've found is that each individual call to `generate_smart_stamp_hash` doesn't take a particularly long time (around 0.5 sec), but it gets called dozens of times during `x check`, and that seems to be what's adding up to 20-30 seconds.
---
https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap/topic/Massive.20regression.20in.20no-op.20.60x.20check.60
cc `@onur-ozkan`