message: Recover when failing to normalize closure signature.
diff: @@ -686,6 +686,7 @@ fn is_fat_ptr<'tcx>(fx: &FunctionCx<'_, '_, 'tcx>, ty: Ty<'tcx>) -> bool {
  substs,
  ty::ClosureKind::FnOnce,
  )
  + .expect("failed to normalize and resolve closure during codegen")
  .polymorphize(fx.tcx);
  let func_ref = fx.get_function_ref(instance);
  let func_addr = fx.bcx.ins().func_addr(fx.pointer_type, func_ref);
  