| error: type parameter `T` is part of concrete type but not used in parameter list for the `impl Trait` type alias | |
| --> $DIR/issue-55872.rs:13:28 | |
| | | |
| LL | fn foo<T>() -> Self::E { | |
| | ____________________________^ | |
| LL | | | |
| LL | | || () | |
| LL | | } | |
| | |_____^ | |
| error: aborting due to previous error | |