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//@ revisions: current next
//@ ignore-compare-mode-next-solver (explicit revisions)
//@[next] compile-flags: -Znext-solver
//@[next] known-bug: #92505
//@[current] check-pass
trait Trait {
type Assoc;
}
impl<T> Trait for T {
type Assoc = T;
}
fn impls_trait<T: Trait>() {}
fn foo<T>()
where
<T as Trait>::Assoc: Trait,
{
// Trying to use `<T as Trait>::Assoc: Trait` to prove `T: Trait`
// requires normalizing `<T as Trait>::Assoc`. We do not normalize
// using impl candidates if there's a where-bound for that trait.
//
// We therefore check whether `T: Trait` is proven by the environment.
// For that we try to apply the `<T as Trait>::Assoc: Trait` candidate,
// trying to normalize its self type results in overflow.
//
// In the old solver we eagerly normalize the environment, ignoring the
// unnormalized `<T as Trait>::Assoc: Trait` where-bound when normalizing
// `<T as Trait>::Asosc`
impls_trait::<T>();
}
fn main() {}
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