| //@ compile-flags: -Znext-solver |
| |
| trait Foo { |
| type Assoc; |
| } |
| |
| trait Bar {} |
| |
| impl<T> Foo for T { |
| type Assoc = i32; |
| } |
| |
| impl<T> Bar for T where T: Foo<Assoc = i32> {} |
| |
| fn require_bar<T: Bar>() {} |
| |
| fn foo<T: Foo>() { |
| // Unlike the classic solver, the new solver previously projected |
| // `<T as Foo>::Assoc = _` down to `i32` even though there's a param-env |
| // candidate here, since we don't assemble any param-env projection |
| // candidates for `T: Foo` alone. |
| // |
| // However, allowing impl candidates shadowed by env candidates results |
| // in multiple issues, so we explicitly hide them, e.g. |
| // |
| // https://github.com/rust-lang/trait-system-refactor-initiative/issues/76 |
| require_bar::<T>(); |
| //~^ ERROR the trait bound `T: Bar` is not satisfied |
| } |
| |
| fn main() {} |
