| // Copyright (c) 2021, 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. | 
 |  | 
 | import 'dart:ffi'; | 
 |  | 
 | import "package:expect/expect.dart"; | 
 | import "package:ffi/ffi.dart"; | 
 |  | 
 | final class DartValueFields extends Union { | 
 |   external Pointer p1; | 
 |   external Pointer p2; | 
 |   external Pointer p3; | 
 |   external Pointer p4; | 
 | } | 
 |  | 
 | void main() { | 
 |   final p = calloc<DartValueFields>(); | 
 |   Expect.equals(0, p.ref.p4.address); | 
 |   calloc.free(p); | 
 | } |