error[E0277]: the trait bound `Self: std::cmp::Eq` is not satisfied
  --> $DIR/wf-trait-default-fn-where-clause.rs:11:31
   |
LL | trait Bar<T:Eq+?Sized> { }
   |             -- required by this bound in `Bar`
...
LL |     fn bar<A>(&self) where A: Bar<Self> {
   |                               ^^^^^^^^^- help: consider further restricting `Self`: `, Self: std::cmp::Eq`
   |                               |
   |                               the trait `std::cmp::Eq` is not implemented for `Self`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0277`.