Assertion `mod_tables.size() == 0 || mod_tables.begin()->first == table' fails upon ALTER IGNORE

--source include/have_partition.inc

--source include/have_innodb.inc

CREATE TABLE t (a INT,  KEY (a)) ENGINE=InnoDB PARTITION BY LIST (a) (

  PARTITION p0 VALUES IN (NULL,1),

  PARTITION pn DEFAULT

 );

INSERT INTO t VALUES (0);

ALTER IGNORE TABLE t FORCE, ALGORITHM = COPY;

DROP TABLE t;

mariadbd: /data/bld/10.11-asan-ubsan/storage/innobase/handler/ha_innodb.cc:15836: void trx_t::reset_and_truncate_undo(const dict_table_t*): Assertion `mod_tables.size() == 0 || mod_tables.begin()->first == table' failed.

260304 11:11:06 [ERROR] /share8t/bld/10.11-asan-ubsan/sql/mariadbd got signal 6 ;

#9  0x00007fbe40245395 in __assert_fail_base (fmt=0x7fbe403b9a90 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x5560fb468120 "mod_tables.size() == 0 || mod_tables.begin()->first == table", file=file@entry=0x5560fb446ac0 "/data/bld/10.11-asan-ubsan/storage/innobase/handler/ha_innodb.cc", line=line@entry=15836, function=function@entry=0x5560fb4680c0 "void trx_t::reset_and_truncate_undo(const dict_table_t*)") at ./assert/assert.c:92

#10 0x00007fbe40253eb2 in __GI___assert_fail (assertion=0x5560fb468120 "mod_tables.size() == 0 || mod_tables.begin()->first == table", file=0x5560fb446ac0 "/data/bld/10.11-asan-ubsan/storage/innobase/handler/ha_innodb.cc", line=15836, function=0x5560fb4680c0 "void trx_t::reset_and_truncate_undo(const dict_table_t*)") at ./assert/assert.c:101

#11 0x00005560f9b5f8f9 in trx_t::reset_and_truncate_undo (this=this@entry=0x7fbe377253c0, table=table@entry=0x618000028920) at /data/bld/10.11-asan-ubsan/storage/innobase/handler/ha_innodb.cc:15836

#12 0x00005560f9afc99e in ha_innobase::extra (this=0x6250002921f8, operation=<optimized out>) at /data/bld/10.11-asan-ubsan/storage/innobase/handler/ha_innodb.cc:15945

#13 0x00005560f9619be3 in extra_cb (h=0x6250002921f8, operation=operation@entry=0x77be300e50d0) at /data/bld/10.11-asan-ubsan/sql/ha_partition.cc:8998

#14 0x00005560f968732e in ha_partition::loop_partitions_over_map (this=this@entry=0x625000291948, part_map=part_map@entry=0x625000293658, callback=callback@entry=0x5560f9619ad9 <extra_cb(handler*, void*)>, param=param@entry=0x77be300e50d0) at /data/bld/10.11-asan-ubsan/sql/ha_partition.cc:9710

#15 0x00005560f968768a in ha_partition::loop_partitions (this=this@entry=0x625000291948, callback=callback@entry=0x5560f9619ad9 <extra_cb(handler*, void*)>, param=param@entry=0x77be300e50d0) at /data/bld/10.11-asan-ubsan/sql/ha_partition.cc:9658

#16 0x00005560f968bc95 in ha_partition::extra (this=0x625000291948, operation=<optimized out>) at /data/bld/10.11-asan-ubsan/sql/ha_partition.cc:9496

#17 0x00005560f7a4eea6 in copy_data_between_tables (thd=thd@entry=0x62c0001f0218, from=from@entry=0x6190000af598, to=to@entry=0x6190000b2798, ignore=<optimized out>, order_num=order_num@entry=0, order=order@entry=0x0, copied=<optimized out>, deleted=<optimized out>, alter_info=<optimized out>, alter_ctx=<optimized out>) at /data/bld/10.11-asan-ubsan/sql/sql_table.cc:12476

#18 0x00005560f7a5db07 in mysql_alter_table (thd=thd@entry=0x62c0001f0218, new_db=<optimized out>, new_name=new_name@entry=0x62c0001f5428, create_info=create_info@entry=0x77be300e9240, table_list=table_list@entry=0x62d0000a0578, recreate_info=recreate_info@entry=0x77be300e8fd0, alter_info=<optimized out>, order_num=<optimized out>, order=<optimized out>, ignore=<optimized out>, if_exists=<optimized out>) at /data/bld/10.11-asan-ubsan/sql/sql_table.cc:11597

#19 0x00005560f7d74376 in Sql_cmd_alter_table::execute (this=<optimized out>, thd=0x62c0001f0218) at /data/bld/10.11-asan-ubsan/sql/sql_alter.cc:688

#20 0x00005560f752cb21 in mysql_execute_command (thd=thd@entry=0x62c0001f0218, is_called_from_prepared_stmt=is_called_from_prepared_stmt@entry=false) at /data/bld/10.11-asan-ubsan/sql/sql_parse.cc:6201

#21 0x00005560f753136c in mysql_parse (thd=thd@entry=0x62c0001f0218, rawbuf=<optimized out>, length=<optimized out>, parser_state=parser_state@entry=0x77be300eaab0) at /data/bld/10.11-asan-ubsan/sql/sql_parse.cc:8223

#22 0x00005560f753a719 in dispatch_command (command=command@entry=COM_QUERY, thd=thd@entry=0x62c0001f0218, packet=packet@entry=0x629000276219 "", packet_length=packet_length@entry=44, blocking=blocking@entry=true) at /data/bld/10.11-asan-ubsan/sql/sql_parse.cc:1924

#23 0x00005560f754741e in do_command (thd=thd@entry=0x62c0001f0218, blocking=blocking@entry=true) at /data/bld/10.11-asan-ubsan/sql/sql_parse.cc:1434

#24 0x00005560f7d43db8 in do_handle_one_connection (connect=<optimized out>, connect@entry=0x60800001d438, put_in_cache=put_in_cache@entry=true) at /data/bld/10.11-asan-ubsan/sql/sql_connect.cc:1475

#25 0x00005560f7d44f15 in handle_one_connection (arg=0x60800001d438) at /data/bld/10.11-asan-ubsan/sql/sql_connect.cc:1387

#26 0x00005560f96ca327 in pfs_spawn_thread (arg=0x617000007e98) at /data/bld/10.11-asan-ubsan/storage/perfschema/pfs.cc:2201

#27 0x00007fbe402a81c4 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442

#28 0x00007fbe4032885c in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

commit e5fed9eaf49419fe81d3695a4323816db1df8e32 (HEAD)

Author: Thirunarayanan Balathandayuthapani

Date:   Thu Feb 26 12:07:23 2026 +0530

    MDEV-36436  Assertion "unexpected references" == 0 after ALTER IGNORE TABLE