backtrace.txt

(gdb) bt
#0  0x0000003eb480c69c in pthread_kill () from /lib64/libpthread.so.0
#1  0x0000000000654562 in handle_fatal_signal (sig=11) at /home/yoku0825/mysql-5.6.17/sql/signal_handler.cc:248
#2  <signal handler called>
#3  mrn_set_bitmap_by_key (map=0x7f82c834d860, key_info=0x1c00) at mrn_table.cpp:1062
#4  0x00007f82d368166f in ha_mroonga::storage_inplace_alter_table (this=0x7f82c8369840, altered_table=0x7f82c8367aa0,
    ha_alter_info=<value optimized out>) at ha_mroonga.cpp:13240
#5  0x000000000072bafd in ha_inplace_alter_table (thd=0x23d5b60, table_list=0x7f82c8005070, table=0x7f82c8368f50,
    altered_table=0x7f82c8367aa0, ha_alter_info=0x7f82dccccfb0, inplace_supported=HA_ALTER_INPLACE_EXCLUSIVE_LOCK,
    target_mdl_request=0x7f82dcccdcd0, alter_ctx=0x7f82dcccbfa0) at /home/yoku0825/mysql-5.6.17/sql/handler.h:2868
#6  mysql_inplace_alter_table (thd=0x23d5b60, table_list=0x7f82c8005070, table=0x7f82c8368f50, altered_table=0x7f82c8367aa0,
    ha_alter_info=0x7f82dccccfb0, inplace_supported=HA_ALTER_INPLACE_EXCLUSIVE_LOCK, target_mdl_request=0x7f82dcccdcd0,
    alter_ctx=0x7f82dcccbfa0) at /home/yoku0825/mysql-5.6.17/sql/sql_table.cc:6498
#7  0x000000000072f15d in mysql_alter_table (thd=0x23d5b60, new_db=0x7f82dccccfb0 "\320\344\314?\177",
    new_name=<value optimized out>, create_info=0x7f82dccce4d0, table_list=0x7f82c8005070, alter_info=0x7f82dccce5b0,
    order_num=0, order=0x0, ignore=false) at /home/yoku0825/mysql-5.6.17/sql/sql_table.cc:8319
#8  0x0000000000822afc in Sql_cmd_alter_table::execute (this=<value optimized out>, thd=0x23d5b60)
    at /home/yoku0825/mysql-5.6.17/sql/sql_alter.cc:313
#9  0x00000000006db054 in mysql_execute_command (thd=0x23d5b60) at /home/yoku0825/mysql-5.6.17/sql/sql_parse.cc:4936
#10 0x00000000006de577 in mysql_parse (thd=0x23d5b60, rawbuf=<value optimized out>, length=<value optimized out>,
    parser_state=<value optimized out>) at /home/yoku0825/mysql-5.6.17/sql/sql_parse.cc:6235
#11 0x00000000006dff0c in dispatch_command (command=COM_QUERY, thd=0x23d5b60, packet=0x7f82dcccfa30 "`[=\002",
    packet_length=52) at /home/yoku0825/mysql-5.6.17/sql/sql_parse.cc:1334
#12 0x00000000006a82ed in do_handle_one_connection (thd_arg=<value optimized out>)
    at /home/yoku0825/mysql-5.6.17/sql/sql_connect.cc:982
#13 0x00000000006a8422 in handle_one_connection (arg=0x23d5b60) at /home/yoku0825/mysql-5.6.17/sql/sql_connect.cc:898
#14 0x0000000000978e47 in pfs_spawn_thread (arg=0x2411e80) at /home/yoku0825/mysql-5.6.17/storage/perfschema/pfs.cc:1860
#15 0x0000003eb4807851 in start_thread () from /lib64/libpthread.so.0
#16 0x0000003eb40e894d in clone () from /lib64/libc.so.6

mroonga_online_alter_table_comment.test

--disable_warnings
INSTALL PLUGIN mroonga SONAME 'ha_mroonga.so';
DROP TABLE IF EXISTS t1;
--enable_warnings

CREATE TABLE t1 (val varchar(32) PRIMARY KEY) Engine= mroonga;
ALTER TABLE t1 ADD FULLTEXT KEY(val) Comment 'dummy';

DROP TABLE t1;
UNINSTALL PLUGIN mroonga;

--exit