// Copyright (c) 2017, the Dart project authors. Please see the AUTHORS file // for details. All rights reserved. Use of this source code is governed by a // BSD-style license that can be found in the LICENSE file. class A {} class B extends A {} class Base { Base(B b); } class C extends Base { C(A a) : super(a); // ^ // [analyzer] COMPILE_TIME_ERROR.ARGUMENT_TYPE_NOT_ASSIGNABLE // [cfe] The argument type 'A' can't be assigned to the parameter type 'B'. } main() { A a = new B(); new C(a); }