error[E0119]: conflicting implementations of trait `Overlap` for type `str`
  --> $DIR/ambiguity-causes-canonical-state-ice-2.rs:18:1
   |
LL | impl<T: ToOwned<Owned = i8> + ?Sized> Overlap for T {}
   | --------------------------------------------------- first implementation here
LL | impl Overlap for str {}
   | ^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `str`

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0119`.