There was an incomplete version of the check in parsing and a second
version in AST validation. This meant that some, but not all, invalid
uses were allowed inside macros/disabled cfgs. It also means that later
passes have a hard time knowing when the let expression is in a valid
location, sometimes causing ICEs.
- Add a field to ExprKind::Let in AST/HIR to mark whether it's in a
valid location.
- Suppress later errors and MIR construction for invalid let
expressions.
Gracefully handle ternary operator
Fixes#112578
~~May not be the best way to do this as it doesn't check for a single `:`, so it could perhaps appear even when the actual issue is just a missing semicolon. May not be the biggest deal, though?~~
Nevermind, got it working properly now ^^
My type ascription
Oh rip it out
Ah
If you think we live too much then
You can sacrifice diagnostics
Don't mix your garbage
Into my syntax
So many weird hacks keep diagnostics alive
Yet I don't even step outside
So many bad diagnostics keep tyasc alive
Yet tyasc doesn't even bother to survive!
Instead of loading the Fluent resources for every crate in
`rustc_error_messages`, each crate generates typed identifiers for its
own diagnostics and creates a static which are pulled together in the
`rustc_driver` crate and provided to the diagnostic emitter.
Signed-off-by: David Wood <david.wood@huawei.com>
Improve diagnostic for missing space in range pattern
Improves the diagnostic in #107425 by turning it into a note explaining the parsing issue.
r? `@compiler-errors`
Adds an additional hint to failures where we encounter an else keyword
while we're parsing an if-let block.
This is likely that the user has accidentally mixed if-let and let...else
together.
Recover from where clauses placed before tuple struct bodies
Open to any suggestions regarding the phrasing of the diagnostic.
Fixes#100790.
`@rustbot` label A-diagnostics
r? diagnostics
Instead of `ast::Lit`.
Literal lowering now happens at two different times. Expression literals
are lowered when HIR is crated. Attribute literals are lowered during
parsing.
This commit changes the language very slightly. Some programs that used
to not compile now will compile. This is because some invalid literals
that are removed by `cfg` or attribute macros will no longer trigger
errors. See this comment for more details:
https://github.com/rust-lang/rust/pull/102944#issuecomment-1277476773
Recover from function pointer types with generic parameter list
Give a more helpful error when encountering function pointer types with a generic parameter list like `fn<'a>(&'a str) -> bool` or `fn<T>(T) -> T` and suggest moving lifetime parameters to a `for<>` parameter list.
I've added a bunch of extra code to properly handle (unlikely?) corner cases like `for<'a> fn<'b>()` (where there already exists a `for<>` parameter list) correctly suggesting `for<'a, 'b> fn()` (merging the lists). If you deem this useless, I can simplify the code by suggesting nothing at all in this case.
I am quite open to suggestions regarding the wording of the diagnostic messages.
Fixes#103487.
``@rustbot`` label A-diagnostics
r? diagnostics
Change #[suggestion_*] attributes to use style="..."
As discussed [on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/336883-i18n/topic/.23100717.20tool_only_span_suggestion), this changes `#[(multipart_)suggestion_{short,verbose,hidden}(...)]` attributes to plain `#[(multipart_)suggestion(...)]` attributes with a `style = "{short,verbose,hidden}"` parameter.
It also adds a new style, `tool-only`, that corresponds to `tool_only_span_suggestion`/`tool_only_multipart_suggestion` and causes the suggestion to not be shown in human-readable output at all.
Best reviewed commit-by-commit, there's a bit of noise in there.
cc #100717 `@compiler-errors`
r? `@davidtwco`
Track where diagnostics were created.
This implements the `-Ztrack-diagnostics` flag, which uses `#[track_caller]` to track where diagnostics are created. It is meant as a debugging tool much like `-Ztreat-err-as-bug`.
For example, the following code...
```rust
struct A;
struct B;
fn main(){
let _: A = B;
}
```
...now emits the following error message:
```
error[E0308]: mismatched types
--> src\main.rs:5:16
|
5 | let _: A = B;
| - ^ expected struct `A`, found struct `B`
| |
| expected due to this
-Ztrack-diagnostics: created at compiler\rustc_infer\src\infer\error_reporting\mod.rs:2275:31
```
