error[E0223]: ambiguous associated type
  --> $DIR/E0223.rs:14:14
   |
LL |     let foo: MyTrait::X;
   |              ^^^^^^^^^^ ambiguous associated type
   |
   = note: specify the type using the syntax `<Type as MyTrait>::X`

error: aborting due to previous error

For more information about this error, try `rustc --explain E0223`.