// Copyright (c) 2016, 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.md file.
// @dart=2.9
class A {
  A(this.x);
}

class B extends A {
  const B();
}

main() {
  new B();
  const B();
}