CREATE TABLE t0 (a INT KEY,b ENUM ('','b','c'));

ALTER TABLE t0 RENAME TO s0;

CREATE TEMPORARY SEQUENCE s0;

CREATE TABLE t0 (id INT DEFAULT NEXTval (s0),a_p_name CHAR(0),a_p_FIRST_NAME VARCHAR(0),t TIMESTAMP);

ALTER TABLE t0 ADD COLUMN a INT,DROP FOREIGN KEY ibfk_0;

mysqld: /test/10.9_dbg/sql/sql_base.cc:963: void close_thread_table(THD*, TABLE**): Assertion `thd->mdl_context.is_lock_owner(MDL_key::TABLE, table->s->db.str, table->s->table_name.str, MDL_SHARED)' failed.

Core was generated by `/test/MD280522-mariadb-10.9.2-linux-x86_64-dbg/bin/mysqld --no-defaults --core-'.

Program terminated with signal SIGABRT, Aborted.

#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50

[Current thread is 1 (Thread 0x14e551d82700 (LWP 1833906))]

(gdb) bt

#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50

#1  0x000014e56a706859 in __GI_abort () at abort.c:79

#2  0x000014e56a706729 in __assert_fail_base (fmt=0x14e56a89c588 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x5644b2355090 "thd->mdl_context.is_lock_owner(MDL_key::TABLE, table->s->db.str, table->s->table_name.str, MDL_SHARED)", file=0x5644b2354a38 "/test/10.9_dbg/sql/sql_base.cc", line=963, function=<optimized out>) at assert.c:92

#3  0x000014e56a717f36 in __GI___assert_fail (assertion=assertion@entry=0x5644b2355090 "thd->mdl_context.is_lock_owner(MDL_key::TABLE, table->s->db.str, table->s->table_name.str, MDL_SHARED)", file=file@entry=0x5644b2354a38 "/test/10.9_dbg/sql/sql_base.cc", line=line@entry=963, function=function@entry=0x5644b2355040 "void close_thread_table(THD*, TABLE**)") at assert.c:101

#4  0x00005644b16dd94b in close_thread_table (thd=thd@entry=0x14e51c000db8, table_ptr=table_ptr@entry=0x14e51c000ea8) at /test/10.9_dbg/sql/sql_base.cc:963

#5  0x00005644b16ddc9e in close_thread_tables (thd=thd@entry=0x14e51c000db8) at /test/10.9_dbg/sql/sql_base.cc:942

#6  0x00005644b16dde95 in close_thread_tables_for_query (thd=thd@entry=0x14e51c000db8) at /test/10.9_dbg/sql/sql_base.cc:771

#7  0x00005644b1775ef6 in mysql_execute_command (thd=thd@entry=0x14e51c000db8, is_called_from_prepared_stmt=is_called_from_prepared_stmt@entry=false) at /test/10.9_dbg/sql/sql_parse.cc:6062

#8  0x00005644b175dbca in mysql_parse (thd=thd@entry=0x14e51c000db8, rawbuf=<optimized out>, length=<optimized out>, parser_state=parser_state@entry=0x14e551d81470) at /test/10.9_dbg/sql/sql_parse.cc:8036

#9  0x00005644b176b198 in dispatch_command (command=command@entry=COM_QUERY, thd=thd@entry=0x14e51c000db8, packet=packet@entry=0x14e51c00b6c9 "ALTER TABLE t0 ADD COLUMN a INT,DROP FOREIGN KEY ibfk_0", packet_length=packet_length@entry=55, blocking=blocking@entry=true) at /test/10.9_dbg/sql/sql_class.h:1364

#10 0x00005644b176d8a0 in do_command (thd=0x14e51c000db8, blocking=blocking@entry=true) at /test/10.9_dbg/sql/sql_parse.cc:1407

#11 0x00005644b18ccd88 in do_handle_one_connection (connect=<optimized out>, connect@entry=0x5644b45214c8, put_in_cache=put_in_cache@entry=true) at /test/10.9_dbg/sql/sql_connect.cc:1418

#12 0x00005644b18cd291 in handle_one_connection (arg=0x5644b45214c8) at /test/10.9_dbg/sql/sql_connect.cc:1312

#13 0x000014e56ac15609 in start_thread (arg=<optimized out>) at pthread_create.c:477

#14 0x000014e56a803293 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95