Bug: Assertion linked_dir_conn_base failed in connection_ap_handshake_send_begin

I am using Tor for Onionbalance. Uploading descriptors for a large OnionBalance config, I crashed Tor with this message:

...
Feb 28 09:59:44.000 [info] connection_free_(): Freeing linked Directory connection [client reading] with 0 bytes on inbuf, 0 on outbuf.
Feb 28 09:59:44.000 [info] circuit_finish_handshake(): Finished building circuit hop:
Feb 28 09:59:44.000 [info] internal circ (length 4, last hop kouettland): $566D30FF44DFBB163F632C439A86CC5B1431EC7C(open) $254EB51B0B85B2FB8A70997875DA493420A30458(open) $9844B981A80B3E4B50897098E2D65167E6AEF127(open) $B9FB493DC3CAC92A1F923DC05A251DCF3F4A4410(open)
Feb 28 09:59:44.000 [info] circuit_send_next_onion_skin(): circuit built!
Feb 28 09:59:44.000 [info] pathbias_count_build_success(): Got success count 273.152447/280.411541 for guard Unnamed ($566D30FF44DFBB163F632C439A86CC5B1431EC7C)
Feb 28 09:59:44.000 [info] internal circ (length 4): $566D30FF44DFBB163F632C439A86CC5B1431EC7C(open) $254EB51B0B85B2FB8A70997875DA493420A30458(open) $9844B981A80B3E4B50897098E2D65167E6AEF127(open) $B9FB493DC3CAC92A1F923DC05A251DCF3F4A4410(open)
Feb 28 09:59:44.000 [info] link_apconn_to_circ(): Looks like completed circuit to [scrubbed] does allow optimistic data for connection to [scrubbed]
Feb 28 09:59:44.000 [info] connection_ap_handshake_send_begin(): Sending relay cell 1 on circ 3620016270 to begin stream 11043.
Feb 28 09:59:44.000 [err] tor_assertion_failed_(): Bug: src/or/connection_edge.c:2443: connection_ap_handshake_send_begin: Assertion linked_dir_conn_base failed; aborting. (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug: Assertion linked_dir_conn_base failed in connection_ap_handshake_send_begin at src/or/connection_edge.c:2443. Stack trace: (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(log_backtrace+0x4c) [0x54c0ea48] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(tor_assertion_failed_+0x90) [0x54c2a0f0] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(connection_ap_handshake_send_begin+0x574) [0x54bbce5c] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(connection_ap_handshake_attach_chosen_circuit+0xf4) [0x54b94438] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(connection_ap_handshake_attach_circuit+0x2ec) [0x54b96ed4] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(connection_ap_attach_pending+0x198) [0x54bbc02c] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(circuit_try_attaching_streams+0x2c) [0x54b93c04] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(circuit_send_next_onion_skin+0x2c8) [0x54b7fe70] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(+0x5c470) [0x54b19470] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(circuit_receive_relay_cell+0x2c8) [0x54b1b8e8] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(command_process_cell+0x324) [0x54b984a8] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(channel_tls_handle_cell+0x238) [0x54b774d8] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(+0x104ad0) [0x54bc1ad0] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(+0xfb40c) [0x54bb840c] (on Tor 0.2.9.9 56788a2489127072)
Feb 28 09:59:44.000 [err] Bug:     tor(+0x3293c) [0x54aef93c] (on Tor 0.2.9.9 56788a2489127072)

OnionBalance and other log/config files available as desired. Config file as follows:

DataDirectory /home/pi/eotk/onionbalance.d
ControlPort unix:/home/pi/eotk/onionbalance.d/tor-control.sock
PidFile /home/pi/eotk/onionbalance.d/tor.pid
Log info file /home/pi/eotk/onionbalance.d/tor.log
SafeLogging 1
HeartbeatPeriod 60 minutes
RunAsDaemon 1
# onionbalance
SocksPort 127.0.0.1:9055
CookieAuthentication 1
MaxClientCircuitsPending 1024

• alec