Description:
Synopsis says everything.
Backtrace is:
#0 0x40122df1 in kill () from /lib/libc.so.6
#1 0x40044f4a in pthread_kill () from /lib/libpthread.so.0
#2 0x40045285 in raise () from /lib/libpthread.so.0
#3 0x40122bca in raise () from /lib/libc.so.6
#4 0x40123de5 in abort () from /lib/libc.so.6
#5 0x08345586 in safe_cond_wait (cond=0x0, mp=0x83ec980, file=0x83826eb "sql_table.cc", line=936) at thr_mutex.c:204
#6 0x08198e1c in safe_remove_from_cache (thd=0x89fbea0, table=0x89f5520) at sql_table.cc:936
#7 0x0819ac3f in mysql_alter_table(THD*, char*, char*, st_ha_create_information*, st_table_list*, List<create_field>&, List<Key>&, List<Alter_drop>&, List<Alter_column>&, st_order*, bool, enum_duplicates, enum_enable_or_disable, bool) (thd=0x89fbea0, new_db=0x89f6310 "bugs", new_name=0x8a30fa8 "t", create_info=0x89fc1fc, table_list=0x8a30fc8, fields=@0x89fc144, keys=@0x89fc138, drop_list=@0x89fc0fc, alter_list=@0x89fc108, order=0x0, drop_primary=false, handle_duplicates=DUP_ERROR, keys_onoff=ENABLE, simple_alter=true) at sql_table.cc:1510
#8 0x081210c2 in mysql_execute_command() () at sql_parse.cc:1841
#9 0x08123fc4 in mysql_parse(THD*, char*, unsigned) (thd=0x89fbea0, inBuf=0x89fbfd0 "\001", length=25) at sql_parse.cc:2887
#10 0x0811eb4c in dispatch_command(enum_server_command, THD*, char*, unsigned) (command=COM_QUERY, thd=0x89fbea0, packet=0x8a28f21 "ALTER TABLE t ENABLE KEYS", packet_length=25) at sql_parse.cc:1049
#11 0x0811e4f3 in do_command(THD*) (thd=0x89fbea0) at sql_parse.cc:924
#12 0x0811da81 in handle_one_connection (arg=0x0) at sql_parse.cc:714
#13 0x40042812 in pthread_start_thread_event () from /lib/libpthread.so.0
How to repeat:
CREATE TABLE t (i int(10) PRIMARY KEY);
ALTER TABLE t DISABLE KEYS;
INSERT DELAYED INTO t VALUES(1);
ALTER TABLE t ENABLE KEYS;