A callback method called when the job queue is empty.

        :return: None

def _job_queue_empty(self):
        """
        A callback method called when the job queue is empty.

        :return: None
        """

        self._iteratively_clean_pending_exits()

        while self._pending_jobs:
            # We don't have any exits remaining. Let's pop out a pending exit
            pending_job = self._get_one_pending_job()
            if pending_job is None:
                continue

            self._insert_job(pending_job)
            self._register_analysis_job(pending_job.func_addr, pending_job)
            break