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//@ 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 satisfy `<dyn Object<U, Output = T> as Object<U>>::Output == T`
}
fn main() {}
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