- Use "#if defined" when checking for DEBUG.

vm/message_queue.cc

 // 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.
 
 #include "vm/message_queue.h"
 
 namespace dart {
 
 MessageQueue::~MessageQueue() {
   // Ensure that all pending messages have been released.
@@ skipping 33 matching lines @@
   if (result == NULL) {
     ml.Wait(millis);
     result = head_;
   }
   if (result != NULL) {
     head_ = result->next_;
     // The following update to tail_ is not strictly needed.
     if (head_ == NULL) {
       tail_ = NULL;
     }
-#if DEBUG
+#if defined(DEBUG)
     result->next_ = result;  // Make sure to trigger ASSERT in Enqueue.
 #endif  // DEBUG
   }
   return result;
 }
 
 
 void MessageQueue::Flush(Dart_Port port) {
   MonitorLocker ml(&monitor_);
   PortMessage* cur = head_;
@@ skipping 26 matching lines @@
   tail_ = NULL;
   while (cur != NULL) {
     PortMessage* next = cur->next_;
     delete cur;
     cur = next;
   }
 }
 
 
 }  // namespace dart