Separate lifetime ident from lifetime resolution in HIR
Drive-by: change how suggested generic args are computed.
Fixes https://github.com/rust-lang/rust/issues/103815
I recommend reviewing commit-by-commit.
Avoid `GenFuture` shim when compiling async constructs
Previously, async constructs would be lowered to "normal" generators, with an additional `from_generator` / `GenFuture` shim in between to convert from `Generator` to `Future`.
The compiler will now special-case these generators internally so that async constructs will *directly* implement `Future` without the need to go through the `from_generator` / `GenFuture` shim.
The primary motivation for this change was hiding this implementation detail in stack traces and debuginfo, but it can in theory also help the optimizer as there is less abstractions to see through.
---
Given this demo code:
```rust
pub async fn a(arg: u32) -> Backtrace {
let bt = b().await;
let _arg = arg;
bt
}
pub async fn b() -> Backtrace {
Backtrace::force_capture()
}
```
I would get the following with the latest stable compiler (on Windows):
```
4: async_codegen:🅱️:async_fn$0
at .\src\lib.rs:10
5: core::future::from_generator::impl$1::poll<enum2$<async_codegen:🅱️:async_fn_env$0> >
at /rustc/897e37553bba8b42751c67658967889d11ecd120\library\core\src\future\mod.rs:91
6: async_codegen:🅰️:async_fn$0
at .\src\lib.rs:4
7: core::future::from_generator::impl$1::poll<enum2$<async_codegen:🅰️:async_fn_env$0> >
at /rustc/897e37553bba8b42751c67658967889d11ecd120\library\core\src\future\mod.rs:91
```
whereas now I get a much cleaner stack trace:
```
3: async_codegen:🅱️:async_fn$0
at .\src\lib.rs:10
4: async_codegen:🅰️:async_fn$0
at .\src\lib.rs:4
```
Previously, async constructs would be lowered to "normal" generators,
with an additional `from_generator` / `GenFuture` shim in between to
convert from `Generator` to `Future`.
The compiler will now special-case these generators internally so that
async constructs will *directly* implement `Future` without the need
to go through the `from_generator` / `GenFuture` shim.
The primary motivation for this change was hiding this implementation
detail in stack traces and debuginfo, but it can in theory also help
the optimizer as there is less abstractions to see through.
Rollup of 8 pull requests
Successful merges:
- #101162 (Migrate rustc_resolve to use SessionDiagnostic, part # 1)
- #103386 (Don't allow `CoerceUnsized` into `dyn*` (except for trait upcasting))
- #103405 (Detect incorrect chaining of if and if let conditions and recover)
- #103594 (Fix non-associativity of `Instant` math on `aarch64-apple-darwin` targets)
- #104006 (Add variant_name function to `LangItem`)
- #104494 (Migrate GUI test to use functions)
- #104516 (rustdoc: clean up sidebar width CSS)
- #104550 (fix a typo)
Failed merges:
- #104554 (Use `ErrorGuaranteed::unchecked_claim_error_was_emitted` less)
r? `@ghost`
`@rustbot` modify labels: rollup
implement binding_shadows
migrate till self-in-generic-param-default
use braces in fluent message as suggested by @compiler-errors.
to fix lock file issue reported by CI
migrate 'unreachable label' error
run formatter
name the variables correctly in fluent file
SessionDiagnostic -> Diagnostic
test "pattern/pat-tuple-field-count-cross.rs" passed
test "resolve/bad-env-capture2.rs" passed
test "enum/enum-in-scope.rs" and other depended on "resolve_binding_shadows_something_unacceptable" should be passed now.
fix crash errors while running test-suite. there might be more.
then_some(..) suits better here.
all tests passed
convert TraitImpl and InvalidAsm. TraitImpl is buggy yet. will fix after receiving help from Zulip
migrate "Ralative-2018"
migrate "ancestor only"
migrate "expected found"
migrate "Indeterminate"
migrate "module only"
revert to the older implementation for now. since this is failing at the moment.
follow the convension for fluent variable
order the diag attribute as suggested in review comment
fix merge error. migrate trait-impl-duplicate
make the changes compatible with "Flatten diagnostic slug modules #103345"
fix merge
remove commented code
merge issues
fix review comments
fix tests
Fix E0433 No Typo Suggestions
Fixes#48676Fixes#87791Fixes#96625Fixes#95462Fixes#101637
Follows up PR #72923
Several open issues refer to the problem that E0433 does not suggest typos like other errors normally do. This fix augments the implementation of PR #72923.
**Background**
When the path of a function call, e.g. `Struct::foo()`, involves names that cannot be resolved, there are two errors that could be emitted by the compiler:
- If `Struct` is not found, it is ``E0433: failed to resolve: use of undeclared type `Struct` ``.
- If `foo` is not found in `Struct`, it is ``E0599: no function or associated item named `foo` found for struct `Struct` in the current scope``
When a name is used as a type, `e.g. fn foo() -> Struct`, and the name cannot be resolved, it is ``E0412: cannot find type `Struct` in this scope``.
Before #72923, `E0433` does not implement any suggestions, and the PR introduces suggestions for missing `use`s. When a resolution error occurs in the path of a function call, it tries to smart resolve just the type part of the path, e.g. `module::Struct` of a call to `module::Struct::foo()`. However, along with the suggestions, the smart-resolve function will report `E0412` since it only knows that it is a type that we cannot resolve instead of being a part of the path. So, the original implementation swap out `E0412` errors returned by the smart-resolve function with the real `E0433` error, but keeps the "missing `use`" suggestions to be reported to the programmer.
**Issue**
The current implementation only reports if there are "missing `use`" suggestions returned by the smart-resolve function; otherwise, it would fall back the normal reporting, which does not emit suggestions. But the smart-resolve function could also produce typo suggestions, which are omitted currently.
Also, it seems like that not all info has been swapped out when there are missing suggestions. The error message underlining the name in the snippet still says ``not found in this scope``, which is a `E0412` messages, if there are `use` suggestions, but says the normal `use of undeclared type` otherwise.
**Fixes**
This fix swaps out all fields in `Diagnostic` returned by the smart-resolve function except for `suggestions` with the current error, and merges the `suggestions` of the returned error and that of the current error together. If there are `use` suggestions, the error is saved to `use_injection` to be reported at the end; otherwise, the error is emitted immediately as `Resolver::report_error` does.
Some tests are updated to use the correct underlining error messages, and one additional test for typo suggestion is added to the test suite.
r? rust-lang/diagnostics
Check uniqueness of impl items by trait item when applicable.
When checking uniqueness of item names in impl blocks, we currently use the same definition of hygiene as for toplevel items. This means that a plain item and one generated by a macro 2.0 do not collide.
This hygiene rule does not match with how impl items resolve to associated trait items. As a consequence, we misdiagnose the trait impls.
This PR proposes to consider that trait impl items are uses of the corresponding trait items during resolution, instead of checking for duplicates later. An error is emitted when a trait impl item is used twice.
There should be no stable breakage, since macros 2.0 are still unstable.
r? ``@petrochenkov``
cc ``@RalfJung``
Fixes https://github.com/rust-lang/rust/issues/71614.
`Res::SelfTy` currently has two `Option`s. When the second one is `Some`
the first one is never consulted. So we can split it into two variants,
`Res::SelfTyParam` and `Res::SelfTyAlias`, reducing the size of `Res`
from 24 bytes to 12. This then shrinks `hir::Path` and
`hir::PathSegment`, which are the HIR types that take up the most space.
The `visit_path_segment` method of both the AST and HIR visitors has a
`path_span` argument that isn't necessary. This commit removes it.
There are two very small and inconsequential functional changes.
- One call to `NodeCollector::insert` now is passed a path segment
identifier span instead of a full path span. This span is only used in
a panic message printed in the case of an internal compiler bug.
- Likewise, one call to `LifetimeCollectVisitor::record_elided_anchor`
now uses a path segment identifier span instead of a full path span.
This span is used to make some `'_` lifetimes.
