Zabbix server process crash

This morning I logged onto my Zabbix box to find that the server process had crashed. I had not made any changes to any configuration for at least a couple of days. It just crashed without warning. The zabbix_server disassembly and log are attached. I have removed all but the crash from the log. The only thing that happened just before the crash was that the Zabbix server sent the configuration to a Proxy and a single host got marked as offline.