diff options
| -rw-r--r-- | src/librustc_trait_selection/traits/select.rs | 11 | ||||
| -rw-r--r-- | src/test/ui/async-await/issue-72590-type-error-sized.rs | 22 | ||||
| -rw-r--r-- | src/test/ui/async-await/issue-72590-type-error-sized.stderr | 28 |
3 files changed, 50 insertions, 11 deletions
diff --git a/src/librustc_trait_selection/traits/select.rs b/src/librustc_trait_selection/traits/select.rs index 9b3381066a1..32bd895f851 100644 --- a/src/librustc_trait_selection/traits/select.rs +++ b/src/librustc_trait_selection/traits/select.rs @@ -1040,17 +1040,6 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { &mut self, stack: &TraitObligationStack<'o, 'tcx>, ) -> SelectionResult<'tcx, SelectionCandidate<'tcx>> { - if stack.obligation.predicate.references_error() { - // If we encounter a `Error`, we generally prefer the - // most "optimistic" result in response -- that is, the - // one least likely to report downstream errors. But - // because this routine is shared by coherence and by - // trait selection, there isn't an obvious "right" choice - // here in that respect, so we opt to just return - // ambiguity and let the upstream clients sort it out. - return Ok(None); - } - if let Some(conflict) = self.is_knowable(stack) { debug!("coherence stage: not knowable"); if self.intercrate_ambiguity_causes.is_some() { diff --git a/src/test/ui/async-await/issue-72590-type-error-sized.rs b/src/test/ui/async-await/issue-72590-type-error-sized.rs new file mode 100644 index 00000000000..00e098d43e0 --- /dev/null +++ b/src/test/ui/async-await/issue-72590-type-error-sized.rs @@ -0,0 +1,22 @@ +// Regression test for issue #72590 +// Tests that we don't emit a spurious "size cannot be statically determined" error +// edition:2018 + +struct Foo { + foo: Nonexistent, //~ ERROR cannot find + other: str +} + +struct Bar { + test: Missing //~ ERROR cannot find +} + +impl Foo { + async fn frob(self) {} //~ ERROR the size +} + +impl Bar { + async fn myfn(self) {} +} + +fn main() {} diff --git a/src/test/ui/async-await/issue-72590-type-error-sized.stderr b/src/test/ui/async-await/issue-72590-type-error-sized.stderr new file mode 100644 index 00000000000..603895b598c --- /dev/null +++ b/src/test/ui/async-await/issue-72590-type-error-sized.stderr @@ -0,0 +1,28 @@ +error[E0412]: cannot find type `Nonexistent` in this scope + --> $DIR/issue-72590-type-error-sized.rs:6:10 + | +LL | foo: Nonexistent, + | ^^^^^^^^^^^ not found in this scope + +error[E0412]: cannot find type `Missing` in this scope + --> $DIR/issue-72590-type-error-sized.rs:11:11 + | +LL | test: Missing + | ^^^^^^^ not found in this scope + +error[E0277]: the size for values of type `str` cannot be known at compilation time + --> $DIR/issue-72590-type-error-sized.rs:15:19 + | +LL | async fn frob(self) {} + | ^^^^ doesn't have a size known at compile-time + | + = help: within `Foo`, the trait `std::marker::Sized` is not implemented for `str` + = note: to learn more, visit <https://doc.rust-lang.org/book/ch19-04-advanced-types.html#dynamically-sized-types-and-the-sized-trait> + = note: required because it appears within the type `Foo` + = note: all local variables must have a statically known size + = help: unsized locals are gated as an unstable feature + +error: aborting due to 3 previous errors + +Some errors have detailed explanations: E0277, E0412. +For more information about an error, try `rustc --explain E0277`. |