// Copyright (c) 2011, 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.

/// @assertion Unless explicitly stated otherwise, all ordinary rules that apply
/// to methods apply to abstract methods.
/// It is a static warning if an instance method m1 overrides an instance member
/// m2, the signature of m2 explicitly specifies a default value for a formal
/// parameter p and the signature of m1 specifies a different default value for
/// p.
/// @description Checks that there are no static warnings if an abstract method
/// overrides another abstract method and overridden method does not explicitly
/// specify a default value for its optional parameter.
/// @author msyabro


abstract class A {
  foo([x]);
}

abstract class C extends A {
  foo([x = 1]);
}

main() {
  C? c = null;
}