| A super trait has been added to an auto trait. | |
| Erroneous code example: | |
| ```compile_fail,E0568 | |
| #![feature(auto_traits)] | |
| auto trait Bound : Copy {} // error! | |
| fn main() {} | |
| ``` | |
| Since an auto trait is implemented on all existing types, adding a super trait | |
| would filter out a lot of those types. In the current example, almost none of | |
| all the existing types could implement `Bound` because very few of them have the | |
| `Copy` trait. | |
| To fix this issue, just remove the super trait: | |
| ``` | |
| #![feature(auto_traits)] | |
| auto trait Bound {} // ok! | |
| fn main() {} | |
| ``` |