Crashes with UNIV_DEBUG as follows:

2015-01-24 20:01:15 7fffb01dc700  InnoDB: Assertion failure in thread 140736148129536 in file lock0lock.cc line 6384
InnoDB: Failing assertion: lock_table_has(trx, index->table, LOCK_IX)
InnoDB: We intentionally generate a memory trap.
InnoDB: Submit a detailed bug report to http://bugs.mysql.com.
InnoDB: If you get repeated assertion failures or crashes, even
InnoDB: immediately after the mysqld startup, there may be
InnoDB: corruption in the InnoDB tablespace. Please refer to
InnoDB: http://dev.mysql.com/doc/refman/5.6/en/forcing-innodb-recovery.html
InnoDB: about forcing recovery.

Program received signal SIGABRT, Aborted.
[Switching to Thread 0x7fffb01dc700 (LWP 30829)]
0x00007ffff5ed0a97 in raise () from /usr/lib/libc.so.6
(gdb) bt
#0  0x00007ffff5ed0a97 in raise () from /usr/lib/libc.so.6
#1  0x00007ffff5ed1e6a in abort () from /usr/lib/libc.so.6
#2  0x00000000009ff9cd in lock_rec_insert_check_and_lock (flags=flags@entry=0, rec=rec@entry=0x7fffd636ad6a "\200", block=0x7fffb841e930, index=index@entry=0x7fff7436edc8, thr=thr@entry=0x7fff74374d00,
    mtr=mtr@entry=0x7fffb01d7860, inherit=0x7fffb01d76b8) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/lock/lock0lock.cc:6384
#3  0x0000000000afce47 in btr_cur_ins_lock_and_undo (flags=flags@entry=0, cursor=cursor@entry=0x7fffb01d77e0, entry=entry@entry=0x7fff7436b8d8, thr=thr@entry=0x7fff74374d00, mtr=mtr@entry=0x7fffb01d7860,
    inherit=inherit@entry=0x7fffb01d76b8) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/btr/btr0cur.cc:1263
#4  0x0000000000b0830d in btr_cur_optimistic_insert (flags=flags@entry=0, cursor=cursor@entry=0x7fffb01d77e0, offsets=offsets@entry=0x7fffb01d77c0, heap=heap@entry=0x7fffb01d77d0,
    entry=entry@entry=0x7fff7436b8d8, rec=rec@entry=0x7fffb01d77d8, big_rec=0x7fffb01d77c8, n_ext=0, thr=0x7fff74374d00, mtr=0x7fffb01d7860)
    at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/btr/btr0cur.cc:1501
#5  0x0000000000a689c5 in row_ins_clust_index_entry_low (flags=flags@entry=0, mode=<optimized out>, mode@entry=2, index=index@entry=0x7fff7436edc8, n_uniq=n_uniq@entry=1, entry=entry@entry=0x7fff7436b8d8,
    n_ext=n_ext@entry=0, thr=0x7fff74374d00) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/row/row0ins.cc:2520
#6  0x0000000000a6a72f in row_ins_clust_index_entry (index=0x7fff7436edc8, entry=0x7fff7436b8d8, thr=thr@entry=0x7fff74374d00, n_ext=n_ext@entry=0)
    at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/row/row0ins.cc:2924
#7  0x0000000000a6a9d2 in row_ins_index_entry (index=<optimized out>, entry=<optimized out>, thr=thr@entry=0x7fff74374d00)
    at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/row/row0ins.cc:3022
#8  0x0000000000a6aa58 in row_ins_index_entry_step (node=node@entry=0x7fff74373ed0, thr=thr@entry=0x7fff74374d00) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/row/row0ins.cc:3099
#9  0x0000000000a6ab3c in row_ins (node=node@entry=0x7fff74373ed0, thr=thr@entry=0x7fff74374d00) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/row/row0ins.cc:3239
#10 0x0000000000a6ad53 in row_ins_step (thr=thr@entry=0x7fff74374d00) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/row/row0ins.cc:3364
#11 0x0000000000a7d094 in row_insert_for_mysql (mysql_rec=mysql_rec@entry=0x7fff743698f0 "\002\231\224\064x\213\200", prebuilt=<optimized out>)
    at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/row/row0mysql.cc:1367
#12 0x00000000009ca33c in ha_innobase::write_row (this=0x7fff74372650, record=<optimized out>) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/innobase/handler/ha_innodb.cc:7843
#13 0x000000000066505f in handler::ha_write_row (this=0x7fff74372650, buf=0x7fff743698f0 "\002\231\224\064x\213\200") at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/handler.cc:7756
#14 0x0000000000603d26 in copy_data_between_tables (from=from@entry=0x7fff741733c0, to=to@entry=0x7fff743662b0, create=..., ignore=ignore@entry=false, order_num=order_num@entry=0, order=order@entry=0x0,
    copied=0x7fffb01d8d28, deleted=0x7fffb01d8d30, keys_onoff=Alter_info::LEAVE_AS_IS, alter_ctx=0x7fffb01d9880) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_table.cc:9321
#15 0x00000000007e471f in mysql_alter_table (thd=thd@entry=0x2e56100, new_db=<optimized out>, new_name=<optimized out>, create_info=create_info@entry=0x7fffb01da4d0, table_list=table_list@entry=0x7fff74362650,
    alter_info=alter_info@entry=0x7fffb01daa40, order_num=0, order=0x0, ignore=false) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_table.cc:8849
#16 0x000000000078e4b4 in mysql_execute_command (thd=thd@entry=0x2e56100) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_parse.cc:3820
---Type <return> to continue, or q <return> to quit---
#17 0x0000000000793ea8 in mysql_parse (thd=thd@entry=0x2e56100, rawbuf=rawbuf@entry=0x7fff74368060 "CREATE INDEX reservations_deleted_expire_idx ON reservations (deleted,expire)", length=length@entry=77,
    parser_state=parser_state@entry=0x7fffb01db7b0) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_parse.cc:7348
#18 0x0000000000794516 in wsrep_mysql_parse (thd=thd@entry=0x2e56100, rawbuf=0x7fff74368060 "CREATE INDEX reservations_deleted_expire_idx ON reservations (deleted,expire)", length=length@entry=77,
    parser_state=parser_state@entry=0x7fffb01db7b0) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_parse.cc:7099
#19 0x0000000000795f7f in dispatch_command (command=command@entry=COM_QUERY, thd=thd@entry=0x2e56100,
    packet=packet@entry=0x2f46e21 "CREATE INDEX reservations_deleted_expire_idx ON reservations (deleted,expire)", packet_length=packet_length@entry=77)
    at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_parse.cc:1625
#20 0x00000000007967f9 in do_command (thd=0x2e56100) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_parse.cc:1129
#21 0x000000000075faf2 in do_handle_one_connection (thd_arg=thd_arg@entry=0x2e56100) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_connect.cc:1557
#22 0x000000000075fc40 in handle_one_connection (arg=arg@entry=0x2e56100) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/sql/sql_connect.cc:1461
#23 0x0000000000c23ee3 in pfs_spawn_thread (arg=0x2f4ae30) at /media/Oort/ncode/percona-xtradb-cluster/pxc56-test/storage/perfschema/pfs.cc:1860
#24 0x00007ffff7bc6314 in start_thread () from /usr/lib/libpthread.so.0
#25 0x00007ffff5f8524d in clone () from /usr/lib/libc.so.6