Do not visit attributes in `ItemLowerer`.
By default, AST visitors visit expressions that appear in key-value attributes.
Those expressions should not be lowered to HIR, as they do not correspond to actually compiled code.
Since an attribute cannot produce meaningful HIR, just skip them altogether.
Fixes https://github.com/rust-lang/rust/issues/81886
Fixes https://github.com/rust-lang/rust/issues/90873
r? `@michaelwoerister`
Suggestion to wrap inner types using 'allocator_api' in tuple
This PR provides a suggestion to wrap the inner types in tuple when being along with 'allocator_api'.
Closes https://github.com/rust-lang/rust/issues/83250
```rust
fn main() {
let _vec: Vec<u8, _> = vec![]; //~ ERROR use of unstable library feature 'allocator_api'
}
```
```diff
error[E0658]: use of unstable library feature 'allocator_api'
--> $DIR/suggest-vec-allocator-api.rs:2:23
|
LL | let _vec: Vec<u8, _> = vec![];
- | ^
+ | ----^
+ | |
+ | help: consider wrapping the inner types in tuple: `(u8, _)`
|
= note: see issue #32838 <https://github.com/rust-lang/rust/issues/32838> for more information
= help: add `#![feature(allocator_api)]` to the crate attributes to enable
```
Fix `non-constant value` ICE (#90878)
This also fixes the same suggestion, which was kind of broken, because it just searched for the last occurence of `const` to replace with a `let`. This works great in some cases, but when there is no const and a leading space to the file, it doesn't work and panic with overflow because it thought that it had found a const.
I also changed the suggestion to only trigger if the `const` and the non-constant value are on the same line, because if they aren't, the suggestion is very likely to be wrong.
Also don't trigger the suggestion if the found `const` is on line 0, because that triggers the ICE.
Asking Esteban to review since he was the last one to change the relevant code.
r? ``@estebank``
Fixes#90878
Clarify error messages caused by re-exporting `pub(crate)` visibility to outside
This PR clarifies error messages and suggestions caused by re-exporting pub(crate) visibility outside the crate.
Here is a small example ([Rust Playground](https://play.rust-lang.org/?version=nightly&mode=debug&edition=2018&gist=e2cd0bd4422d4f20e6522dcbad167d3b)):
```rust
mod m {
pub(crate) enum E {}
}
pub use m::E;
fn main() {}
```
This code is compiled to:
```
error[E0365]: `E` is private, and cannot be re-exported
--> prog.rs:4:9
|
4 | pub use m::E;
| ^^^^ re-export of private `E`
|
= note: consider declaring type or module `E` with `pub`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0365`.
```
However, enum `E` is actually public to the crate, not private totally—nevertheless, rustc treats `pub(crate)` and private visibility as the same on the error messages. They are not clear and should be segmented distinctly.
By applying changes in this PR, the error message below will be the following message that would be clearer:
```
error[E0365]: `E` is only public to inside of the crate, and cannot be re-exported outside
--> prog.rs:4:9
|
4 | pub use m::E;
| ^^^^ re-export of crate public `E`
|
= note: consider declaring type or module `E` with `pub`
error: aborting due to previous error
For more information about this error, try `rustc --explain E0365`.
```
This function parameter attribute was introduced in https://github.com/rust-lang/rust/pull/44866 as an intermediate step in implementing `impl Trait`, it's not necessary or used anywhere by itself.
This also fixes the same suggestion, which was kind of broken, because it just searched for the last occurence of `const` to replace with a `let`. This works great in some cases, but when there is no const and a leading space to the file, it doesn't work and panic with overflow because it thought that it had found a const.
I also changed the suggestion to only trigger if the `const` and the non-constant value are on the same line, because if they aren't, the suggestion is very likely to be wrong.
Also don't trigger the suggestion if the found `const` is on line 0, because that triggers the ICE.
Type inference for inline consts
Fixes#78132Fixes#78174Fixes#81857Fixes#89964
Perform type checking/inference of inline consts in the same context as the outer def, similar to what is currently done to closure.
Doing so would require `closure_base_def_id` of the inline const to return the outer def, and since `closure_base_def_id` can be called on non-local crate (and thus have no HIR available), a new `DefKind` is created for inline consts.
The type of the generated anon const can capture lifetime of outer def, so we couldn't just use the typeck result as the type of the inline const's def. Closure has a similar issue, and it uses extra type params `CK, CS, U` to capture closure kind, input/output signature and upvars. I use a similar approach for inline consts, letting it have an extra type param `R`, and then `typeof(InlineConst<[paremt generics], R>)` would just be `R`. In borrowck region requirements are also propagated to the outer MIR body just like it's currently done for closure.
With this PR, inline consts in expression position are quitely usable now; however the usage in pattern position is still incomplete -- since those does not remain in the MIR borrowck couldn't verify the lifetime there. I have left an ignored test as a FIXME.
Some disucssions can be found on [this Zulip thread](https://rust-lang.zulipchat.com/#narrow/stream/260443-project-const-generics/topic/inline.20consts.20typeck).
cc `````@spastorino````` `````@lcnr`````
r? `````@nikomatsakis`````
`````@rustbot````` label A-inference F-inline_const T-compiler
TraitKind -> Trait
TyAliasKind -> TyAlias
ImplKind -> Impl
FnKind -> Fn
All `*Kind`s in AST are supposed to be enums.
Tuple structs are converted to braced structs for the types above, and fields are reordered in syntactic order.
Also, mutable AST visitor now correctly visit spans in defaultness, unsafety, impl polarity and constness.
Improve and test cross-crate hygiene
- Decode the parent expansion for traits and enums in `rustc_resolve`, this was already being used for resolution in typeck
- Avoid suggesting importing names with def-site hygiene, since it's often not useful
- Add more tests
r? `@petrochenkov`
Emit description of the ambiguity as a note.
Co-authored-by: Noah Lev <camelidcamel@gmail.com>
Co-authored-by: Vadim Petrochenkov <vadim.petrochenkov@gmail.com>
Do not mention a reexported item if it's private
Fixes#90113
The _actual_ regression was introduced in #73652, then #88838 made it worse. This fixes the issue by not counting such an import as a candidate.
resolve: Use `NameBinding` for local variables and generic parameters
`NameBinding` is a structure used for representing any name introduction (an item, or import, or even a built-in).
Except that local variables and generic parameters weren't represented as `NameBinding`s, for this reason they requires separate paths in name resolution code in several places.
This PR introduces `NameBinding`s for local variables as well and simplifies all the code working with them leaving only the `NameBinding` paths.
Adopt let_else across the compiler
This performs a substitution of code following the pattern:
```
let <id> = if let <pat> = ... { identity } else { ... : ! };
```
To simplify it to:
```
let <pat> = ... { identity } else { ... : ! };
```
By adopting the `let_else` feature (cc #87335).
The PR also updates the syn crate because the currently used version of the crate doesn't support `let_else` syntax yet.
Note: Generally I'm the person who *removes* usages of unstable features from the compiler, not adds more usages of them, but in this instance I think it hopefully helps the feature get stabilized sooner and in a better state. I have written a [comment](https://github.com/rust-lang/rust/issues/87335#issuecomment-944846205) on the tracking issue about my experience and what I feel could be improved before stabilization of `let_else`.
Index and hash HIR as part of lowering
Part of https://github.com/rust-lang/rust/pull/88186
~Based on https://github.com/rust-lang/rust/pull/88880 (see merge commit).~
Once HIR is lowered, it is later indexed by the `index_hir` query and hashed for `crate_hash`. This PR moves those post-processing steps to lowering itself. As a side objective, the HIR crate data structure is refactored as an `IndexVec<LocalDefId, Option<OwnerInfo<'hir>>>` where `OwnerInfo` stores all the relevant information for an HIR owner.
r? `@michaelwoerister`
cc `@petrochenkov`
rustc_span: `Ident::invalid` -> `Ident::empty`
The equivalent for `Symbol`s was renamed some time ago (`kw::Invalid` -> `kw::Empty`), and it makes sense to do the same thing for `Ident`s as well.
Some "parenthesis" and "parentheses" fixes
"Parenthesis" is the singular (e.g. one `(` or one `)`) and "parentheses" is the plural (multiple `(` or `)`s) and this is not hard to mix up so here are some fixes for that.
Inspired by #89958
The syn crate has gained support for let_else syntax in version 1.0.76,
see https://github.com/dtolnay/syn/pull/1057 .
In the three instances that use let_else, we've sent code through an
attr macro, which would create compile errors when there was no
let_else support in syn. To avoid this, we ran
`cargo +nightly update -p syn` for updating the syn crate.
This performs a substitution of code following the pattern:
let <id> = if let <pat> = ... { identity } else { ... : ! };
To simplify it to:
let <pat> = ... { identity } else { ... : ! };
By adopting the let_else feature.
suggestion for typoed crate or module
Previously, the compiler didn't suggest similarly named crates or modules. This pull request adds a suggestion for typoed crates or modules.
#76208
before:
```
error[E0433]: failed to resolve: use of undeclared type or module `chono`
--> src/main.rs:2:5
|
2 | use chono::prelude::*;
| ^^^^^ use of undeclared type or module `chono`
```
after:
```
error[E0433]: failed to resolve: use of undeclared type or module `chono`
--> src/main.rs:2:5
|
2 | use chono::prelude::*;
| ^^^^^
| |
| use of undeclared crate or module `chono`
| help: a similar crate or module exists: `chrono`
```
