@Override
  protected boolean doSlowStartup() {
    tempWorkDir = options.getWorkDir() == null;
    if (tempWorkDir) {
      try {
        options.setWorkDir(Utility.makeTemporaryDirectory(null, "gwtc"));
      } catch (IOException e) {
        System.err.println("Unable to create hosted mode work directory");
        e.printStackTrace();
        return false;
      }
    }

    TreeLogger branch = getTopLogger().branch(TreeLogger.TRACE, "Linking modules");
    Event slowStartupEvent = SpeedTracerLogger.start(DevModeEventType.SLOW_STARTUP);
    try {
      for (ModuleDef module : startupModules.values()) {
        TreeLogger loadLogger =
            branch.branch(
                TreeLogger.DEBUG,
                "Bootstrap link for command-line module '" + module.getCanonicalName() + "'");
        link(loadLogger, module);
      }
    } catch (UnableToCompleteException e) {
      // Already logged.
      return false;
    } finally {
      slowStartupEvent.end();
    }
    return true;
  }