Tweak value suggestions in `borrowck` and `hir_analysis`
Unify the output of `suggest_assign_value` and `ty_kind_suggestion`.
Ideally we'd make these a single function, but doing so would likely require modify the crate dependency tree.
Rework ptr-to-ref conversion suggestion for method calls
If we have a value `z` of type `*const u8` and try to call `z.to_string()`, the upstream compiler will show you a note suggesting to call `<*const u8>::as_ref` first.
This PR extends that:
- The note will only be shown when the method would exist on the corresponding reference type
- It can now suggest any of `<*const u8>::as_ref`, `<*mut u8>::as_ref` and `<*mut u8>::as_mut`, depending on what the method needs.
I didn't introduce a `help` message because that's not a good idea with `unsafe` functions (and you'd also need to unwrap the `Option<&_>` somehow).
People should check the safety requirements.
For the simplest case
```rust
fn main() {
let x = 8u8;
let z: *const u8 = &x;
// issue #21596
println!("{}", z.to_string()); //~ ERROR E0599
}
```
the output changes like this:
```diff
error[E0599]: `*const u8` doesn't implement `std::fmt::Display`
--> $DIR/suggest-convert-ptr-to-ref.rs:5:22
|
LL | println!("{}", z.to_string());
| ^^^^^^^^^ `*const u8` cannot be formatted with the default formatter
|
- = note: try using `<*const T>::as_ref()` to get a reference to the type behind the pointer: https://doc.rust-lang.org/std/primitive.pointer.html#method.as_ref
- = note: using `<*const T>::as_ref()` on a pointer which is unaligned or points to invalid or uninitialized memory is undefined behavior
+note: the method `to_string` exists on the type `&u8`
+ --> $SRC_DIR/alloc/src/string.rs:LL:COL
+ = note: try using the unsafe method `<*const T>::as_ref` to get an optional reference to the value behind the pointer: https://doc.rust-lang.org/std/primitive.pointer.html#method.as_ref
= note: the following trait bounds were not satisfied:
`*const u8: std::fmt::Display`
which is required by `*const u8: ToString`
```
I removed the separate note about the safety requirements because it was incomplete and the linked doc page already has the information you need.
Fixes#83695, but that's more of a side effect. The upstream compiler already suggests the right method name here.
Provide suggestion to dereference closure tail if appropriate
When encoutnering a case like
```rust
use std::collections::HashMap;
fn main() {
let vs = vec![0, 0, 1, 1, 3, 4, 5, 6, 3, 3, 3];
let mut counts = HashMap::new();
for num in vs {
let count = counts.entry(num).or_insert(0);
*count += 1;
}
let _ = counts.iter().max_by_key(|(_, v)| v);
```
produce the following suggestion
```
error: lifetime may not live long enough
--> $DIR/return-value-lifetime-error.rs:13:47
|
LL | let _ = counts.iter().max_by_key(|(_, v)| v);
| ------- ^ returning this value requires that `'1` must outlive `'2`
| | |
| | return type of closure is &'2 &i32
| has type `&'1 (&i32, &i32)`
|
help: dereference the return value
|
LL | let _ = counts.iter().max_by_key(|(_, v)| **v);
| ++
```
Fix#50195.
Use `suggest_impl_trait` in return type suggestion on type error
Discovered while doing other refactoring. Review with whitespace disabled.
r? estebank
Use `fn` ptr signature instead of `{closure@..}` in infer error
When suggesting a type on inference error, do not use `{closure@..}`. Instead, replace with an appropriate `fn` ptr.
On the error message, use `short_ty_string` and write long types to disk.
```
error[E0284]: type annotations needed for `Select<{closure@lib.rs:2782:13}, _, Expression<'_>, _>`
--> crates/lang/src/parser.rs:41:13
|
41 | let lit = select! {
| ^^^
42 | Token::Int(i) = e => Expression::new(Expr::Lit(ast::Lit::Int(i.parse().unwrap())), e.span()),
| ---- type must be known at this point
|
= note: the full type name has been written to '/home/gh-estebank/iowo/target/debug/deps/lang-e2d6e25819442273.long-type-4587393693885174369.txt'
= note: cannot satisfy `<_ as chumsky::input::Input<'_>>::Span == SimpleSpan`
help: consider giving `lit` an explicit type, where the type for type parameter `I` is specified
|
41 | let lit: Select<for<'a, 'b> fn(tokens::Token<'_>, &'a mut MapExtra<'_, 'b, _, _>) -> Option<Expression<'_>>, _, Expression<'_>, _> = select! {
| +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
```
instead of
```
error[E0284]: type annotations needed for `Select<{closure@/home/gh-estebank/.cargo/registry/src/index.crates.io-6f17d22bba15001f/chumsky-1.0.0-alpha.6/src/lib.rs:2782:13: 2782:28}, _, Expression<'_>, _>`
--> crates/lang/src/parser.rs:41:13
|
41 | let lit = select! {
| ^^^
42 | Token::Int(i) = e => Expression::new(Expr::Lit(ast::Lit::Int(i.parse().unwrap())), e.span()),
| ---- type must be known at this point
|
= note: cannot satisfy `<_ as chumsky::input::Input<'_>>::Span == SimpleSpan`
help: consider giving `lit` an explicit type, where the type for type parameter `I` is specified
|
41 | let lit: Select<{closure@/home/gh-estebank/.cargo/registry/src/index.crates.io-6f17d22bba15001f/chumsky-1.0.0-alpha.6/src/lib.rs:2782:13: 2782:28}, _, Expression<'_>, _> = select! {
| ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
```
Address #123630 (test missing).
Skip `unused_parens` report for `Paren(Path(..))` in macro.
fixes#120642
In following code, `unused_parens` suggest change `<($($rest),*)>::bar()` to `<$rest>::bar()` which will cause another err: `error: variable 'rest' is still repeating at this depth`：
```rust
trait Foo {
fn bar();
}
macro_rules! problem {
($ty:ident) => {
impl<$ty: Foo> Foo for ($ty,) {
fn bar() { <$ty>::bar() }
}
};
($ty:ident $(, $rest:ident)*) => {
impl<$ty: Foo, $($rest: Foo),*> Foo for ($ty, $($rest),*) {
fn bar() {
<$ty>::bar();
<($($rest),*)>::bar()
}
}
problem!($($rest),*);
}
}
```
I think maybe we can handle this by avoid warning for `Paren(Path(..))` in the macro. Is this reasonable approach?
`f16` and `f128` step 4: basic library support
This is the next step after https://github.com/rust-lang/rust/pull/121926, another portion of https://github.com/rust-lang/rust/pull/114607
Tracking issue: https://github.com/rust-lang/rust/issues/116909
This PR adds the most basic operations to `f16` and `f128` that get lowered as LLVM intrinsics. This is a very small step but it seemed reasonable enough to add unopinionated basic operations before the larger modules that are built on top of them.
r? ```@Amanieu``` since you were pretty involved in the RFC
cc ```@compiler-errors```
```@rustbot``` label +T-libs-api +S-blocked +F-f16_and_f128
Propagate temporary lifetime extension into if and match.
This PR makes this work:
```rust
let a = if true {
..;
&temp() // used to error, but now gets lifetime extended
} else {
..;
&temp() // used to error, but now gets lifetime extended
};
```
and
```rust
let a = match () {
_ => {
..;
&temp() // used to error, but now gets lifetime extended
}
};
```
to make it consistent with:
```rust
let a = {
..;
&temp() // lifetime is extended
};
```
This is one small part of [the temporary lifetimes work](https://github.com/rust-lang/lang-team/issues/253).
This part is backwards compatible (so doesn't need be edition-gated), because all code affected by this change previously resulted in a hard error.
Further cleanup cfgs in the UI test suite
This PR does more cleanup of cfgs in our UI test suite, in preparation for adding automatic always on check-cfg (but is IMO worth landing even without that follow up).
To be more specific this PR:
- replaces (the last remaining) never true cfgs by the `FALSE` cfg
- fix `proc-macro/derive-helper-configured.rs` *(typo in directive)*
- and comment some current unused `#[cfg_attr]` *(missing revisions)*
Follow-up to https://github.com/rust-lang/rust/pull/123577.
Only assert for child/parent projection compatibility AFTER checking that theyre coming from the same place
This assertion doesn't make sense until we check that these captures are actually equivalent.
Fixes#123697
<sub>Some days I wonder how I even write code that works...</sub>
Add support to intrinsics fallback body
Before this fix, the call to `body()` would crash, since `has_body()` would return true, but we would try to retrieve the body of an intrinsic which is not allowed.
Instead, the `Instance::body()` function will now convert an Intrinsic into an Item before retrieving its body.
Note: I also changed how we monomorphize the instance body. Unfortunately, the call still ICE for some shims.
r? `@oli-obk`
Add `REDUNDANT_LIFETIMES` lint to detect lifetimes which are semantically redundant
There already is a `UNUSED_LIFETIMES` lint which is fired when we detect where clause bounds like `where 'a: 'static`, however, it doesn't use the full power of lexical region resolution to detect failures.
Right now `UNUSED_LIFETIMES` is an `Allow` lint, though presumably we could bump it to warn? I can (somewhat) easily implement a structured suggestion so this can be rustfix'd automatically, since we can just walk through the HIR body, replacing instances of the redundant lifetime.
Fixes#118376
r? lcnr
Rollup of 7 pull requests
Successful merges:
- #121884 (Port exit-code run-make test to use rust)
- #122200 (Unconditionally show update nightly hint on ICE)
- #123568 (Clean up tests/ui by removing `does-nothing.rs`)
- #123609 (Don't use bytepos offsets when computing semicolon span for removal)
- #123612 (Set target-abi module flag for RISC-V targets)
- #123633 (Store all args in the unsupported Command implementation)
- #123668 (async closure coroutine by move body MirPass refactoring)
Failed merges:
- #123701 (Only assert for child/parent projection compatibility AFTER checking that theyre coming from the same place)
r? `@ghost`
`@rustbot` modify labels: rollup
Don't use bytepos offsets when computing semicolon span for removal
Causes problems when we recover confusable characters w/ a different byte width
Fixes#123607
Clean up tests/ui by removing `does-nothing.rs`
In [a previous PR](https://github.com/rust-lang/rust/pull/123297#issuecomment-2039887806), it was suggested that this test be removed:
> it's testing a basic diagnostic for an unknown variable (added over a decade ago for https://github.com/rust-lang/rust/issues/154) that is already covered by probably dozens or hundreds of other tests.
It was then suggested that [opening a new PR](https://github.com/rust-lang/rust/pull/123563#discussion_r1554654102) for this would be more organized.
I'm setting this as a draft, as:
1. The tests/ui directory is rather disorganized, a large quantity of tests are not even contained inside their own directories. This PR could turn into "clean up the UI tests directory", if I were to place everything into categories (for example, everything related to CLI flags could get placed in a cli directory).
2. This will have a merge conflict with #123563 should that get merged. I trust that _this time_, I won't run into [The Incident](https://github.com/rust-lang/rust/pull/123297#issuecomment-2041137569) while rebasing. Edit: Yay, I did it properly!
Unconditionally show update nightly hint on ICE
Instead of trying to guess if a update nightly hint should be shown (by checking for system time, querying version and channel info etc.), just show the update nightly hint for nightly compilers. This avoids breaking tests that match on ICE test outputs on nightly/dev channels.
> Another issue is that the outdated nightly hint triggers for ICE tests, causing a mismatch with the test expectation. There doesn't seem to be any env var to suppress this.
See <https://rust-lang.zulipchat.com/#narrow/stream/326414-t-infra.2Fbootstrap/topic/stage0.20compiletest.20broken/near/425543681> for context.
Port exit-code run-make test to use rust
As part of https://github.com/rust-lang/rust/issues/121876
~~As draft because formatting will fail because `x fmt` isn't working for me for some reason, I'll debug that later, just opening this now for review, will mark as ready when formatting is fixed~~ (misleading message from x fmt)
cc `@jieyouxu`
When suggesting a type on inference error, do not use `{closure@..}`.
Instead, replace with an appropriate `fn` ptr.
On the error message, use `short_ty_string` and write long types to
disk.
```
error[E0284]: type annotations needed for `Select<{closure@lib.rs:2782:13}, _, Expression<'_>, _>`
--> crates/lang/src/parser.rs:41:13
|
41 | let lit = select! {
| ^^^
42 | Token::Int(i) = e => Expression::new(Expr::Lit(ast::Lit::Int(i.parse().unwrap())), e.span()),
| ---- type must be known at this point
|
= note: the full type name has been written to '/home/gh-estebank/iowo/target/debug/deps/lang-e2d6e25819442273.long-type-4587393693885174369.txt'
= note: cannot satisfy `<_ as chumsky::input::Input<'_>>::Span == SimpleSpan`
help: consider giving `lit` an explicit type, where the type for type parameter `I` is specified
|
41 | let lit: Select<for<'a, 'b> fn(tokens::Token<'_>, &'a mut MapExtra<'_, 'b, _, _>) -> Option<Expression<'_>>, _, Expression<'_>, _> = select! {
| +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
```
instead of
```
error[E0284]: type annotations needed for `Select<{closure@/home/gh-estebank/.cargo/registry/src/index.crates.io-6f17d22bba15001f/chumsky-1.0.0-alpha.6/src/lib.rs:2782:13: 2782:28}, _, Expression<'_>, _>`
--> crates/lang/src/parser.rs:41:13
|
41 | let lit = select! {
| ^^^
42 | Token::Int(i) = e => Expression::new(Expr::Lit(ast::Lit::Int(i.parse().unwrap())), e.span()),
| ---- type must be known at this point
|
= note: cannot satisfy `<_ as chumsky::input::Input<'_>>::Span == SimpleSpan`
help: consider giving `lit` an explicit type, where the type for type parameter `I` is specified
|
41 | let lit: Select<{closure@/home/gh-estebank/.cargo/registry/src/index.crates.io-6f17d22bba15001f/chumsky-1.0.0-alpha.6/src/lib.rs:2782:13: 2782:28}, _, Expression<'_>, _> = select! {
| ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
```
Fix#123630.
Unify the output of `suggest_assign_value` and `ty_kind_suggestion`.
Ideally we'd make these a single function, but doing so would likely require modify the crate dependency tree.
This commit does three things:
1. replaces (the last remaining) never true cfgs by the FALSE cfg
2. fix derive-helper-configured.rs (typo in directive)
3. and comment some current unused #[cfg_attr] (missing revisions)
I added this back in 111999, but I no longer think it's a good idea
- It had to get scaled back to only power-of-two things to not break a bunch of targets
- LLVM seems to be getting better at memcpy removal anyway
- Introducing vector instructions has seemed to sometimes (115515) make autovectorization worse
So this removes it from the codegen crates entirely, and instead just tries to use <https://doc.rust-lang.org/nightly/nightly-rustc/rustc_codegen_ssa/traits/builder/trait.BuilderMethods.html#method.typed_place_copy> instead of direct `memcpy` so things will still use load/store for immediates.
