CREATE TEMPORARY TABLE t (f INT);

INSERT INTO t VALUES (1);

ALTER TABLE t FORCE;

#3  <signal handler called>

#4  0x000055bf88ce19cb in MDL_ticket::downgrade_lock (this=0x0, type=MDL_SHARED_UPGRADABLE) at /data/src/bb-11.2-oalter/sql/mdl.cc:3001

#5  0x000055bf88b74b4e in copy_data_between_tables (thd=0x7f9578000dc8, from=0x7f95782295c8, to=0x7f95780442f8, create=..., ignore=false, order_num=0, order=0x0, copied=0x7f95885dcea8, deleted=0x7f95885dceb0, keys_onoff=Alter_info::LEAVE_AS_IS, alter_ctx=0x7f95885de440, online=true) at /data/src/bb-11.2-oalter/sql/sql_table.cc:11901

#6  0x000055bf88b6f053 in mysql_alter_table (thd=0x7f9578000dc8, new_db=0x7f9578005af0, new_name=0x7f9578005f40, create_info=0x7f95885df260, table_list=0x7f9578015610, recreate_info=0x7f95885df130, alter_info=0x7f95885df170, order_num=0, order=0x0, ignore=false, if_exists=false) at /data/src/bb-11.2-oalter/sql/sql_table.cc:11139

#7  0x000055bf88cd127f in Sql_cmd_alter_table::execute (this=0x7f9578015d28, thd=0x7f9578000dc8) at /data/src/bb-11.2-oalter/sql/sql_alter.cc:563

#8  0x000055bf8893a69e in mysql_execute_command (thd=0x7f9578000dc8, is_called_from_prepared_stmt=false) at /data/src/bb-11.2-oalter/sql/sql_parse.cc:5764

#9  0x000055bf88946115 in mysql_parse (thd=0x7f9578000dc8, rawbuf=0x7f9578015540 "ALTER TABLE t FORCE", length=19, parser_state=0x7f95885e0370) at /data/src/bb-11.2-oalter/sql/sql_parse.cc:7767

#10 0x000055bf8891e7c3 in dispatch_command (command=COM_QUERY, thd=0x7f9578000dc8, packet=0x7f957800baa9 "ALTER TABLE t FORCE", packet_length=19, blocking=true) at /data/src/bb-11.2-oalter/sql/sql_parse.cc:1892

#11 0x000055bf8891b8e4 in do_command (thd=0x7f9578000dc8, blocking=true) at /data/src/bb-11.2-oalter/sql/sql_parse.cc:1405

#12 0x000055bf88cbb18d in do_handle_one_connection (connect=0x55bf8e1f8a88, put_in_cache=true) at /data/src/bb-11.2-oalter/sql/sql_connect.cc:1416

#13 0x000055bf88cbabb8 in handle_one_connection (arg=0x55bf8e1e8698) at /data/src/bb-11.2-oalter/sql/sql_connect.cc:1318

#14 0x000055bf896393fd in pfs_spawn_thread (arg=0x55bf8e1f85f8) at /data/src/bb-11.2-oalter/storage/perfschema/pfs.cc:2201

#15 0x00007f958dea7fd4 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442

#16 0x00007f958df285bc in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81