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//@ revisions: current next
//@ ignore-compare-mode-next-solver (explicit revisions)
//@[next] compile-flags: -Znext-solver
//@ check-pass
#![allow(warnings)]
trait Trait<U> {
type Assoc;
}
impl<T> Trait<u64> for T {
type Assoc = T;
}
fn lazy_init<T: Trait<U>, U>() -> (T, <T as Trait<U>>::Assoc) {
todo!()
}
fn foo<T: Trait<u32, Assoc = T>>(x: T) {
// When considering impl candidates to be equally valid as env candidates
// this ends up being ambiguous as `U` can be both `u32ยด and `u64` here.
//
// This is acceptable breakage but we should still note that it's
// theoretically breaking.
let (delayed, mut proj) = lazy_init::<_, _>();
proj = x;
let _: T = delayed;
}
fn main() {}
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