Review

In line 180 of JUnitXMLReporter, synchronized collection m_allTests is iterated
in an unsynchronized manner, but according to Oracle Java 7 API specification,
although a synchronizedList is thread-safe for list manipulations like insertion and
deletion, manual synchronization is required when the collection is iterated.
Failure to do so might result in non-deterministic behavior.
The fix synchronizes m_allTests when iterating.

• missing/condition/synchronization

org/testng/reporters/JUnitXMLReporter.java

generateReport(ITestContext)

class JUnitXMLReporter {
  /**
   * generate the XML report given what we know from all the test results
   */
  protected void generateReport(ITestContext context) {

      XMLStringBuffer document= new XMLStringBuffer();
      document.addComment("Generated by " + getClass().getName());

      Properties attrs= new Properties();
      attrs.setProperty(XMLConstants.ATTR_ERRORS, "0");
      attrs.setProperty(XMLConstants.ATTR_FAILURES, "" + m_numFailed);
      try {
        attrs.setProperty(XMLConstants.ATTR_HOSTNAME, InetAddress.getLocalHost().getHostName());
      } catch (UnknownHostException e) {
        // ignore
      }
      Set<String> packages = getPackages(context);
      if (packages.size() > 0) {
        attrs.setProperty(XMLConstants.ATTR_NAME, context.getCurrentXmlTest().getName());
//        attrs.setProperty(XMLConstants.ATTR_PACKAGE, packages.iterator().next());
      }

      attrs.setProperty(XMLConstants.ATTR_TESTS, "" + m_allTests.size());
      attrs.setProperty(XMLConstants.ATTR_TIME, ""
          + ((context.getEndDate().getTime() - context.getStartDate().getTime()) / 1000.0));

      Date timeStamp = Calendar.getInstance().getTime();
      attrs.setProperty(XMLConstants.ATTR_TIMESTAMP, timeStamp.toGMTString());

      document.push(XMLConstants.TESTSUITE, attrs);
//      document.addEmptyElement(XMLConstants.PROPERTIES);

      for(ITestResult tr : m_configIssues) {
        createElement(document, tr);
      }
      for(ITestResult tr : m_allTests) {
        createElement(document, tr);
      }

      document.pop();
      Utils.writeUtf8File(context.getOutputDirectory(),generateFileName(context) + ".xml", document.toXML());
  }

}

class IterateSynchronized {
  private List<ITestResult> syncL = Collections.synchronizedList(new ArrayList<ITestResult>());
  
  void pattern() {
    synchronized(syncL) {
      for (ITestResult tr : syncL) {
        long elapsedTimeMillis= tr.getEndMillis() - tr.getStartMillis();
        String name= tr.getMethod().isTest() ? tr.getName() : Utils.detailedMethodName(tr.getMethod(), false);
      }
    }
  }
}