Problem found during RQG testing

- threads=10

- grammar = <derivate of instant_alter.yy>

on

10.4 7075d7fce626ee915c9ae9308cfb4a8120e83e44 2019-02-04T16:07:12+01:00

...

InnoDB: Assertion failure in file storage/innobase/dict/dict0dict.cc line 6181

InnoDB: We intentionally generate a memory trap.

...

Query (0x7f9888012fb0): ALTER TABLE `table200_innodb_int_autoinc` ADD FULLTEXT INDEX idx_7 (`col_varchar_255_default_null`) /* E_R Thread10 QNO 42 CON_ID 23 */

# 2019-02-04T20:27:03 [99425] | Connection ID (thread ID): 23

# 2019-02-04T20:27:03 [99425] | Status: NOT_KILLED

...

#3  <signal handler called>

#4  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:58

#5  0x00007f9948f0337a in __GI_abort () at abort.c:89

#6  0x0000561a3a7277b5 in ut_dbg_assertion_failed (expr=0x0, file=0x561a3aec5e40 "storage/innobase/dict/dict0dict.cc", line=6181) at storage/innobase/ut/ut0dbg.cc:60

#7  0x0000561a3a7ec406 in dict_table_check_for_dup_indexes (table=0x7f989c022248, check=CHECK_ALL_COMPLETE) at storage/innobase/dict/dict0dict.cc:6181

#8  0x0000561a3a5469b0 in ha_innobase::commit_inplace_alter_table (this=0x7f98900204e0, altered_table=0x7f9888065328, ha_alter_info=0x7f99314fcb80, commit=true) at storage/innobase/handler/handler0alter.cc:11150

#9  0x0000561a3a2ddf0a in handler::ha_commit_inplace_alter_table (this=0x7f98900204e0, altered_table=0x7f9888065328, ha_alter_info=0x7f99314fcb80, commit=true) at sql/handler.cc:4666

#10 0x0000561a3a07ff6e in mysql_inplace_alter_table (thd=0x7f9888000a98, table_list=0x7f98880131f0, table=0x7f989003e128, altered_table=0x7f9888065328, ha_alter_info=0x7f99314fcb80, inplace_supported=HA_ALTER_INPLACE_NOCOPY_LOCK, target_mdl_request=0x7f99314fcdb0, alter_ctx=0x7f99314fd360) at sql/sql_table.cc:7594

#11 0x0000561a3a085db6 in mysql_alter_table (thd=0x7f9888000a98, new_db=0x7f9888005130, new_name=0x7f9888005500, create_info=0x7f99314fdf50, table_list=0x7f98880131f0, alter_info=0x7f99314fde90, order_num=0, order=0x0, ignore=false) at sql/sql_table.cc:9692

#12 0x0000561a3a110c21 in Sql_cmd_alter_table::execute (this=0x7f9888013948, thd=0x7f9888000a98) at sql/sql_alter.cc:499

#13 0x0000561a39fad5d5 in mysql_execute_command (thd=0x7f9888000a98) at sql/sql_parse.cc:6306

#14 0x0000561a39fb29ba in mysql_parse (thd=0x7f9888000a98, rawbuf=0x7f9888012fb0 "ALTER TABLE `table200_innodb_int_autoinc` ADD FULLTEXT INDEX idx_7 (`col_varchar_255_default_null`) /* E_R Thread10 QNO 42 CON_ID 23 */", length=135, parser_state=0x7f99314ff260, is_com_multi=false, is_next_command=false) at sql/sql_parse.cc:8117

#15 0x0000561a39f9df0c in dispatch_command (command=COM_QUERY, thd=0x7f9888000a98, packet=0x7f9888009bc9 "ALTER TABLE `table200_innodb_int_autoinc` ADD FULLTEXT INDEX idx_7 (`col_varchar_255_default_null`) /* E_R Thread10 QNO 42 CON_ID 23 */ ", packet_length=136, is_com_multi=false, is_next_command=false) at sql/sql_parse.cc:1803

#16 0x0000561a39f9c855 in do_command (thd=0x7f9888000a98) at sql/sql_parse.cc:1356

#17 0x0000561a3a10ab7f in do_handle_one_connection (connect=0x561a3d0fb8b8) at sql/sql_connect.cc:1398

#18 0x0000561a3a10a8e3 in handle_one_connection (arg=0x561a3d0fb8b8) at sql/sql_connect.cc:1301

#19 0x00007f9949d466da in start_thread (arg=0x7f9931500700) at pthread_create.c:456

RQG log with backtrace etc. : MDEV-18476.log  (MariaDB 10.4)