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# Error code E0568

A super trait has been added to an auto trait.

Erroneous code example:

    #![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() {}