Program: 90656
Project: 90656
Buggy source:
/** 
 * Tear down the configuration.
 */
@Override public void stop(){
  this.setStopping();
  LOGGER.trace("String_Node_Str",this);
  final LoggerContextFactory factory=LogManager.getFactory();
  if (factory instanceof Log4jContextFactory) {
    ContextSelector selector=((Log4jContextFactory)factory).getSelector();
    if (selector instanceof AsyncLoggerContextSelector) {
    }
  }
  Set<LoggerConfig> alreadyStopped=new HashSet<LoggerConfig>();
  int asyncLoggerConfigCount=0;
  for (  final LoggerConfig logger : loggers.values()) {
    if (logger instanceof AsyncLoggerConfig) {
      logger.stop();
      asyncLoggerConfigCount++;
      alreadyStopped.add(logger);
    }
  }
  if (root instanceof AsyncLoggerConfig) {
    root.stop();
    asyncLoggerConfigCount++;
    alreadyStopped.add(root);
  }
  LOGGER.trace("String_Node_Str",asyncLoggerConfigCount);
  final Appender[] array=appenders.values().toArray(new Appender[appenders.size()]);
  int asyncAppenderCount=0;
  for (int i=array.length - 1; i >= 0; --i) {
    if (array[i] instanceof AsyncAppender) {
      array[i].stop();
      asyncAppenderCount++;
    }
  }
  LOGGER.trace("String_Node_Str",asyncAppenderCount);
  int appenderCount=0;
  for (int i=array.length - 1; i >= 0; --i) {
    if (array[i].isStarted()) {
      array[i].stop();
      appenderCount++;
    }
  }
  LOGGER.trace("String_Node_Str",appenderCount);
  int loggerCount=0;
  for (  final LoggerConfig logger : loggers.values()) {
    logger.clearAppenders();
    if (alreadyStopped.contains(logger)) {
      continue;
    }
    logger.stop();
    loggerCount++;
  }
  LOGGER.trace("String_Node_Str",loggerCount);
  if (!alreadyStopped.contains(root)) {
    root.stop();
  }
  super.stop();
  if (advertiser != null && advertisement != null) {
    advertiser.unadvertise(advertisement);
  }
  LOGGER.debug("String_Node_Str",this);
}

Fixed version (ground truth):
/** 
 * Tear down the configuration.
 */
@Override public void stop(){
  this.setStopping();
  LOGGER.trace("String_Node_Str",this);
  final LoggerContextFactory factory=LogManager.getFactory();
  if (factory instanceof Log4jContextFactory) {
    ContextSelector selector=((Log4jContextFactory)factory).getSelector();
    if (selector instanceof AsyncLoggerContextSelector) {
    }
  }
  final Set<LoggerConfig> alreadyStopped=new HashSet<LoggerConfig>();
  int asyncLoggerConfigCount=0;
  for (  final LoggerConfig logger : loggers.values()) {
    if (logger instanceof AsyncLoggerConfig) {
      logger.stop();
      asyncLoggerConfigCount++;
      alreadyStopped.add(logger);
    }
  }
  if (root instanceof AsyncLoggerConfig) {
    root.stop();
    asyncLoggerConfigCount++;
    alreadyStopped.add(root);
  }
  LOGGER.trace("String_Node_Str",asyncLoggerConfigCount);
  final Appender[] array=appenders.values().toArray(new Appender[appenders.size()]);
  int asyncAppenderCount=0;
  for (int i=array.length - 1; i >= 0; --i) {
    if (array[i] instanceof AsyncAppender) {
      array[i].stop();
      asyncAppenderCount++;
    }
  }
  LOGGER.trace("String_Node_Str",asyncAppenderCount);
  int appenderCount=0;
  for (int i=array.length - 1; i >= 0; --i) {
    if (array[i].isStarted()) {
      array[i].stop();
      appenderCount++;
    }
  }
  LOGGER.trace("String_Node_Str",appenderCount);
  int loggerCount=0;
  for (  final LoggerConfig logger : loggers.values()) {
    logger.clearAppenders();
    if (alreadyStopped.contains(logger)) {
      continue;
    }
    logger.stop();
    loggerCount++;
  }
  LOGGER.trace("String_Node_Str",loggerCount);
  if (!alreadyStopped.contains(root)) {
    root.stop();
  }
  super.stop();
  if (advertiser != null && advertisement != null) {
    advertiser.unadvertise(advertisement);
  }
  LOGGER.debug("String_Node_Str",this);
}