| //@ revisions: current next |
| //@[next] compile-flags: -Znext-solver |
| //@ ignore-compare-mode-next-solver (explicit revisions) |
| //@[current] check-pass |
| //@[current] known-bug: #57893 |
| |
| // Should fail. Because we see an impl that uses a certain associated type, we |
| // type-check assuming that impl is used. However, this conflicts with the |
| // "implicit impl" that we get for trait objects, violating coherence. |
| |
| trait Object<U> { |
| type Output; |
| } |
| |
| impl<T: ?Sized, U> Object<U> for T { |
| type Output = U; |
| } |
| |
| fn foo<T: ?Sized, U>(x: <T as Object<U>>::Output) -> U { |
| x |
| } |
| |
| #[allow(dead_code)] |
| fn transmute<T, U>(x: T) -> U { |
| foo::<dyn Object<U, Output = T>, U>(x) |
| //[next]~^ ERROR type annotations needed: cannot normalize `<dyn Object<U, Output = T> as Object<U>>::Output` |
| } |
| |
| fn main() {} |
