let found_span = found_did.and_then(|did| self.tcx.hir().span_if_local(did));
if self.reported_closure_mismatch.borrow().contains(&(span, found_span)) {
let found_span = found_did.and_then(|did| self.tcx.hir().span_if_local(did));
if self.reported_closure_mismatch.borrow().contains(&(span, found_span)) {