update overflow handling in the new trait solver
implements https://hackmd.io/QY0dfEOgSNWwU4oiGnVRLw?view. I want to clean up this doc and add it to the rustc-dev-guide, but I think this PR is ready for merge as is, even without the dev-guide entry.
r? `@compiler-errors`
Add separate feature gate for async fn track caller
This patch adds a feature gate `async_fn_track_caller` that is separate from `closure_track_caller`. This is to allow enabling `async_fn_track_caller` separately.
Fixes#110009
Improve spans for indexing expressions
fixes#114388
Indexing is similar to method calls in having an arbitrary left-hand-side and then something on the right, which is the main part of the expression. Method calls already have a span for that right part, but indexing does not. This means that long method chains that use indexing have really bad spans, especially when the indexing panics and that span in coverted into a panic location.
This does the same thing as method calls for the AST and HIR, storing an extra span which is then put into the `fn_span` field in THIR.
r? compiler-errors
Indexing is similar to method calls in having an arbitrary
left-hand-side and then something on the right, which is the main part
of the expression. Method calls already have a span for that right part,
but indexing does not. This means that long method chains that use
indexing have really bad spans, especially when the indexing panics and
that span in coverted into a panic location.
This does the same thing as method calls for the AST and HIR, storing an
extra span which is then put into the `fn_span` field in THIR.
Rework upcasting confirmation to support upcasting to fewer projections in target bounds
This PR implements a modified trait upcasting algorithm that is resilient to changes in the number of associated types in the bounds of the source and target trait objects.
It does this by equating each bound of the target trait ref individually against the bounds of the source trait ref, rather than doing them all together by constructing a new trait object.
#### The new way we do trait upcasting confirmation
1. Equate the target trait object's principal trait ref with one of the supertraits of the source trait object's principal.
fdcab310b2/compiler/rustc_trait_selection/src/traits/select/mod.rs (L2509-L2525)
2. Make sure that every auto trait in the *target* trait object is present in the source trait ref's bounds.
fdcab310b2/compiler/rustc_trait_selection/src/traits/select/mod.rs (L2559-L2562)
3. For each projection in the *target* trait object, make sure there is exactly one projection that equates with it in the source trait ref's bound. If there is more than one, bail with ambiguity.
fdcab310b2/compiler/rustc_trait_selection/src/traits/select/mod.rs (L2526-L2557)
* Since there may be more than one that applies, we probe first to check that there is exactly one, then we equate it outside of a probe once we know that it's unique.
4. Make sure the lifetime of the source trait object outlives the lifetime of the target.
<details>
<summary>Meanwhile, this is how we used to do upcasting:</summary>
1. For each supertrait of the source trait object, take that supertrait, append the source object's projection bounds, and the *target* trait object's auto trait bounds, and make this into a new object type:
d12c6e947c/compiler/rustc_trait_selection/src/traits/select/confirmation.rs (L915-L929)
2. Then equate it with the target trait object:
d12c6e947c/compiler/rustc_trait_selection/src/traits/select/confirmation.rs (L936)
This will be a type mismatch if the target trait object has fewer projection bounds, since we compare the bounds structurally in relate:
d12c6e947c/compiler/rustc_middle/src/ty/relate.rs (L696-L698)
</details>
Fixes#114035
Also fixes#114113, because I added a normalize call in the old solver.
r? types
Perform OpaqueCast field projection on HIR, too.
fixes#105819
This is necessary for closure captures in 2021 edition, as they capture individual fields, not the full mentioned variables. So it may try to capture a field of an opaque (because the hidden type is known to be something with a field).
See https://github.com/rust-lang/rust/pull/99806 for when and why we added OpaqueCast to MIR.
Forbid old-style `simd_shuffleN` intrinsics
Don't merge before https://github.com/rust-lang/packed_simd/pull/350 has made its way to crates.io
We used to support specifying the lane length of simd_shuffle ops by attaching the lane length to the name of the intrinsic (like `simd_shuffle16`). After this PR, you cannot do that anymore, and need to instead either rely on inference of the `idx` argument type or specify it as `simd_shuffle::<_, [u32; 16], _>`.
r? `@workingjubilee`
Add `internal_features` lint
Implements https://github.com/rust-lang/compiler-team/issues/596
Also requires some more test blessing for codegen tests etc
`@jyn514` had the idea of just `allow`ing the lint by default in the test suite. I'm not sure whether this is a good idea, but it's definitely one worth considering. Additional input encouraged.
const validation: point at where we found a pointer but expected an integer
Instead of validation just printing "unable to turn pointer into bytes", make this a regular validation error that says where in the value the bad pointer was found. Also distinguish "expected integer, got pointer" from "expected pointer, got partial pointer or mix of pointers".
To avoid duplicating things too much I refactored the diagnostics for validity a bit, so that "got uninit, expected X" and "got pointer, expected X" can share the "X" part. Also all the errors emitted for validation are now grouped under `const_eval_validation` so that they are in a single group in the ftl file.
r? `@oli-obk`
parser: more friendly hints for handling `async move` in the 2015 edition
Fixes#114219
An error is emitted when encountering an async move block in the 2015 edition.
Another appropriate location to raise an error is after executing [let path = this.parse_path(PathStyle::Expr)?](https://github.com/rust-lang/rust/blob/master/compiler/rustc_parse/src/parser/stmt.rs#L152), but it seems somewhat premature to invoke `create_err` at that stage.
Expand, rename and improve `incorrect_fn_null_checks` lint
This PR,
- firstly, expand the lint by now linting on references
- secondly, it renames the lint `incorrect_fn_null_checks` -> `useless_ptr_null_checks`
- and thirdly it improves the lint by catching `ptr::from_mut`, `ptr::from_ref`, as well as `<*mut _>::cast` and `<*const _>::cast_mut`
Fixes https://github.com/rust-lang/rust/issues/113601
cc ```@est31```
It lints against features that are inteded to be internal to the
compiler and standard library. Implements MCP #596.
We allow `internal_features` in the standard library and compiler as those
use many features and this _is_ the standard library from the "internal to the compiler and
standard library" after all.
Marking some features as internal wasn't exactly the most scientific approach, I just marked some
mostly obvious features. While there is a categorization in the macro,
it's not very well upheld (should probably be fixed in another PR).
We always pass `-Ainternal_features` in the testsuite
About 400 UI tests and several other tests use internal features.
Instead of throwing the attribute on each one, just always allow them.
There's nothing wrong with testing internal features^^
Infer type in irrefutable slice patterns with fixed length as array
Fixes https://github.com/rust-lang/rust/issues/76342
In irrefutable slice patterns with a fixed length, we can infer the type as an array type. We now choose to prefer some implementations over others, e.g. in:
```
struct Zeroes;
const ARR: [usize; 2] = [0; 2];
const ARR2: [usize; 2] = [2; 2];
impl Into<&'static [usize; 2]> for Zeroes {
fn into(self) -> &'static [usize; 2] {
&ARR
}
}
impl Into<&'static [usize]> for Zeroes {
fn into(self) -> &'static [usize] {
&ARR2
}
}
fn main() {
let &[a, b] = Zeroes.into();
}
```
We now prefer the impl candidate `impl Into<&'static [usize; 2]> for Zeroes`, it's not entirely clear to me that this is correct, but given that the slice impl would require a type annotation anyway, this doesn't seem unreasonable.
r? `@lcnr`
Fix suggestion spans for expr from macro expansions
### Issue #112007: rustc shows expanded `writeln!` macro in code suggestion
#### Before This PR
```
help: consider using a semicolon here
|
6 | };
| +
help: you might have meant to return this value
--> C:\Users\hayle\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib/rustlib/src/rust\library\core\src\macros\mod.rs:557:9
|
55| return $dst.write_fmt($crate::format_args_nl!($($arg)*));
| ++++++ +
```
#### After This PR
```
help: consider using a semicolon here
|
LL | };
| +
help: you might have meant to return this value
|
LL | return writeln!(w, "but not here");
| ++++++ +
```
### Issue #110017: `format!` `.into()` suggestion deletes the `format` macro
#### Before This PR
```
help: call `Into::into` on this expression to convert `String` into `Box<dyn std::error::Error>`
--> /Users/eric/.rustup/toolchains/nightly-aarch64-apple-darwin/lib/rustlib/src/rust/library/alloc/src/macros.rs:121:12
|
12| res.into()
| +++++++
```
#### After This PR
```
help: call `Into::into` on this expression to convert `String` into `Box<dyn std::error::Error>`
|
LL | Err(format!("error: {x}").into())
| +++++++
```
---
Fixes#112007.
Fixes#110017.
This patch adds a feature gate `async_fn_track_caller` that is separate from `closure_track_caller`. This is to allow enabling `async_fn_track_caller` separately.
Fixes#110009
Rollup of 5 pull requests
Successful merges:
- #114079 (Use `upvar_tys` in more places, make it return a list)
- #114166 (Add regression test for resolving `--extern libc=test.rlib`)
- #114321 (get auto traits for parallel rustc)
- #114335 (fix and extend ptr_comparison test)
- #114347 (x.py print more detailed format files and untracked files count)
r? `@ghost`
`@rustbot` modify labels: rollup
