When encountering
```rust
fn f<T>(a: T, b: T) -> std::cmp::Ordering {
a.cmp(&b) //~ ERROR E0599
}
```
output
```
error[E0599]: no method named `cmp` found for type parameter `T` in the current scope
--> $DIR/method-on-unbounded-type-param.rs:2:7
|
LL | fn f<T>(a: T, b: T) -> std::cmp::Ordering {
| - method `cmp` not found for this type parameter
LL | a.cmp(&b)
| ^^^ method cannot be called on `T` due to unsatisfied trait bounds
|
= help: items from traits can only be used if the type parameter is bounded by the trait
help: the following traits define an item `cmp`, perhaps you need to restrict type parameter `T` with one of them:
|
LL | fn f<T: Ord>(a: T, b: T) -> std::cmp::Ordering {
| +++++
LL | fn f<T: Iterator>(a: T, b: T) -> std::cmp::Ordering {
| ++++++++++
```
Fix#120186.
Remove some unnecessary check logic for lang items in HIR typeck
Obvious bugs with `#[no_core]` do not deserve customized recovery logic, since they are bugs we do not expect users to ever encounter, and if users are experimenting with `#[no_core]`, they should really be familiar with the compiler implementation.
These error recoveries are implemented now only where issues have been reported in the past, rather than systematically validating lang items.
See https://github.com/rust-lang/compiler-team/issues/620
> In particular, one-off fixes for particular assumptions about lang items or intrinsics that introduce additional complexity into the compiler are not accepted.
r? Nilstrieb
Improve error message when `cargo build` is used to build the compiler
Inspired by #76446.
Doing it for `core` is probably higher value but also way harder because tools like cargo or rustc-build-sysroot would need to be fixed first, which I don't feel like doing.
Revert outdated version of "Add the wasm32-wasi-preview2 target"
An outdated version of #119616 was merged in rollup #120309.
This reverts those changes to enable #119616 to “retain the intended diff” after a rebase.
```@rylev``` has agreed that this would be the cleanest approach with respect to the history.
Unblocks #119616.
r? ```@petrochenkov``` or compiler or libs
Remove various `has_errors` or `err_count` uses
follow up to https://github.com/rust-lang/rust/pull/119895
r? `@nnethercote` since you recently did something similar.
There are so many more of these, but I wanted to get a PR out instead of growing the commit list indefinitely. The commits all work on their own and can be reviewed commit by commit.
Deduplicate more sized errors on call exprs
Change the implicit `Sized` `Obligation` `Span` for call expressions to include the whole expression. This aids the existing deduplication machinery to reduce the number of errors caused by a single unsized expression.
Suppress unhelpful diagnostics for unresolved top level attributes
Fixes#118455, unresolved top level attribute error didn't imported prelude and already have emitted an error, report builtin macro and attributes error by the way, so `check_invalid_crate_level_attr` in can ignore them.
Also fixes#89566, fixes#67107.
r? `@petrochenkov`
The query accept arbitrary DefIds, not just owner DefIds.
The return can be an `Option` because if there are no nodes, then it doesn't matter whether it's due to NonOwner or Phantom.
Also rename the query to `opt_hir_owner_nodes`.
Be more careful about interpreting a label/lifetime as a mistyped char literal.
Currently the parser interprets any label/lifetime in certain positions as a mistyped char literal, on the assumption that the trailing single quote was accidentally omitted. In such cases it gives an error with a suggestion to add the trailing single quote, and then puts the appropriate char literal into the AST. This behaviour was introduced in #101293.
This is reasonable for a case like this:
```
let c = 'a;
```
because `'a'` is a valid char literal. It's less reasonable for a case like this:
```
let c = 'abc;
```
because `'abc'` is not a valid char literal.
Prior to #120329 this could result in some sub-optimal suggestions in error messages, but nothing else. But #120329 changed `LitKind::from_token_lit` to assume that the char/byte/string literals it receives are valid, and to assert if not. This is reasonable because the lexer does not produce invalid char/byte/string literals in general. But in this "interpret label/lifetime as unclosed char literal" case the parser can produce an invalid char literal with contents such as `abc`, which triggers an assertion failure.
This PR changes the parser so it's more cautious about interpreting labels/lifetimes as unclosed char literals.
Fixes#120397.
r? `@compiler-errors`
Fixes footnote handling in rustdoc
Fixes#100638.
You can now declare footnotes like this:
```rust
//! Reference to footnotes A[^1], B[^2] and C[^3].
//!
//! [^1]: Footnote A.
//! [^2]: Footnote B.
//! [^3]: Footnote C.
```
r? `@notriddle`
Make the coroutine def id of an async closure the child of the closure def id
Adjust def collection to make the (inner) coroutine returned by an async closure be a def id child of the (outer) closure. This makes it easy to map from coroutine -> closure by using `tcx.parent`, since currently it's not trivial to do this.
Because it's almost always static.
This makes `impl IntoDiagnosticArg for DiagnosticArgValue` trivial,
which is nice.
There are a few diagnostics constructed in
`compiler/rustc_mir_build/src/check_unsafety.rs` and
`compiler/rustc_mir_transform/src/errors.rs` that now need symbols
converted to `String` with `to_string` instead of `&str` with `as_str`,
but that' no big deal, and worth it for the simplifications elsewhere.
only assemble alias bound candidates for rigid aliases
fixes https://github.com/rust-lang/trait-system-refactor-initiative/issues/77
This also causes `<Wrapper<?0> as Trait>::Unwrap: Trait` to always be ambig, as we now normalize the self type before checking whether it is an inference variable.
I cannot think of an approach to the underlying issues here which does not require the "may-define means must-define" restriction for opaque types. Going to go ahead with this and added this restriction to the tracking issue for the new solver to make sure we don't stabilize it without getting types + lang signoff here.
r? `@compiler-errors`
Do not attempt to provide an accurate suggestion for `impl Trait`
in bare trait types when linting. Instead, only do the object
safety check when an E0782 is already going to be emitted in the
2021 edition.
Fix#120241.