/*
 * Copyright (c) 2019, 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 The [==] operator in constant expressions was defined such that
 * [e1 != null] was only allowed if [e1] had one of the "primitive" system
 * types. Users had to rewrite their code to [!identical(e1, null)]. This was
 * changed so that the [==] expression is always allowed as long as one of the
 * operands is [null].
 * @description Checks that compile-time exception is thrown if one of the [==]
 * operand is [null] and another one is not a potentially constant.
 * @author iarkh@unipro.ru
 */

class A {}
A? a;

main() {
  const bool a1 = (a == null);
//                 ^
// [analyzer] unspecified
// [cfe] unspecified
}