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//@ compile-flags: -Znext-solver
// When we're solving `<T as Foo>::Assoc = i32`, we actually first solve
// `<T as Foo>::Assoc = ?1t`, then unify `?1t` with `i32`. That goal
// with the inference variable is ambiguous when there are >1 param-env
// candidates.
// We don't unify the RHS of a projection goal eagerly when solving, both
// for caching reasons and partly to make sure that we don't make the new
// trait solver smarter than it should be.
// This is (as far as I can tell) a forwards-compatible decision, but if you
// make this test go from fail to pass, be sure you understand the implications!
trait Foo {
type Assoc;
}
trait Bar {}
impl<T> Bar for T where T: Foo<Assoc = i32> {}
fn needs_bar<T: Bar>() {}
fn foo<T: Foo<Assoc = i32> + Foo<Assoc = u32>>() {
needs_bar::<T>();
//~^ ERROR type annotations needed: cannot normalize
}
fn main() {}
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