CURRENT_TEST: innodb.innodb-index-online
mysqltest: At line 403: query 'reap' failed with wrong errno <Unknown> (2013): 'Lost connection to server during query', instead of ER_LOCK_WAIT_TIMEOUT (1205)...

The result from queries just before the failure was:
< snip >
CHECK TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	check	status	OK
SET GLOBAL innodb_max_purge_lag_wait=0;
ALTER TABLE t1 ADD UNIQUE INDEX c3p5(c3(5));
ERROR 23000: Duplicate entry 'NULL' for key 'c3p5'
UPDATE t1 SET c3 = NULL WHERE c3 = '';
SET lock_wait_timeout = 1;
SET DEBUG_SYNC = 'row_log_apply_before SIGNAL c3p5_created WAIT_FOR ins_done';
ALTER TABLE t1 ADD UNIQUE INDEX c3p5(c3(5));
connection default;
SET DEBUG_SYNC = 'now WAIT_FOR c3p5_created';
SELECT sf.name, sf.pos FROM INFORMATION_SCHEMA.INNODB_SYS_INDEXES si
INNER JOIN INFORMATION_SCHEMA.INNODB_SYS_FIELDS sf
ON si.index_id = sf.index_id WHERE si.name = '?c3p5';
name	pos
c3	0
SET DEBUG_SYNC = 'ib_after_row_insert SIGNAL ins_done WAIT_FOR ddl_timed_out';
INSERT INTO t1 VALUES(347,33101,NULL);
connection con1;

More results from queries before failure can be found in /dev/shm/var/2/log/innodb-index-online.log
