substs: SubstsRef<'tcx>,
) -> Option<Instance<'tcx>> {
debug!("resolve_for_vtable(def_id={:?}, substs={:?})", def_id, substs);
substs: SubstsRef<'tcx>,
) -> Option<Instance<'tcx>> {
debug!("resolve_for_vtable(def_id={:?}, substs={:?})", def_id, substs);