assert_eq!(trait_ref.def_id, coerce_unsized_trait);
let target = trait_ref.substs.type_at(1);
debug!("visit_implementation_of_coerce_unsized: {:?} -> {:?} (bound)", source, target);
assert_eq!(trait_ref.def_id, coerce_unsized_trait);
let target = trait_ref.substs.type_at(1);
debug!("visit_implementation_of_coerce_unsized: {:?} -> {:?} (bound)", source, target);