Assertion in create_ref_for_key() fails with disabled derived_merge

--source include/have_sequence.inc

set optimizer_switch='derived_merge=off';

CREATE TABLE t AS SELECT 1 AS a FROM seq_1_to_2;

SELECT md5(a) IN (SELECT * FROM (SELECT '' FROM t) as x) FROM t;

Program terminated with signal SIGABRT, Aborted.

#0  __pthread_kill_implementation (threadid=<optimized out>, signo=6, no_tid=0) at ./nptl/pthread_kill.c:44

#1  __pthread_kill_internal (threadid=<optimized out>, signo=6) at ./nptl/pthread_kill.c:89

#2  __GI___pthread_kill (threadid=<optimized out>, signo=6) at ./nptl/pthread_kill.c:100

#3  0x000060e18ddff4b1 in my_write_core (sig=6) at /src/mariadb2/mysys/stacktrace.c:424

#4  0x000060e18d407288 in handle_fatal_signal (sig=6) at /src/mariadb2/sql/signal_handler.cc:298

#5  <signal handler called>

#6  __pthread_kill_implementation (threadid=<optimized out>, signo=6, no_tid=0) at ./nptl/pthread_kill.c:44

#7  __pthread_kill_internal (threadid=<optimized out>, signo=6) at ./nptl/pthread_kill.c:89

#8  __GI___pthread_kill (threadid=<optimized out>, signo=signo@entry=6) at ./nptl/pthread_kill.c:100

#9  0x00007e7d6904579e in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26

#10 0x00007e7d690288cd in __GI_abort () at ./stdlib/abort.c:73

#11 0x00007e7d69028830 in __assert_fail_base (fmt=<optimized out>, assertion=<optimized out>, file=<optimized out>, line=<optimized out>, function=<optimized out>) at ./assert/assert.c:118

#12 0x000060e18d02880a in create_ref_for_key (join=0x7e7d5001d350, j=0x7e7d50071c38, org_keyuse=0x7e7d50075908, allow_full_scan=true, used_tables=4611686018427387905) at /src/mariadb2/sql/sql_select.cc:13686

#13 0x000060e18d027cc8 in JOIN::get_best_combination (this=0x7e7d5001d350) at /src/mariadb2/sql/sql_select.cc:13437

#14 0x000060e18d0069c0 in JOIN::optimize_stage2 (this=0x7e7d5001d350) at /src/mariadb2/sql/sql_select.cc:2772

#15 0x000060e18d0067c3 in JOIN::optimize_inner (this=0x7e7d5001d350) at /src/mariadb2/sql/sql_select.cc:2751

#16 0x000060e18d003a8b in JOIN::optimize (this=0x7e7d5001d350) at /src/mariadb2/sql/sql_select.cc:2006

#17 0x000060e18cf4b78a in st_select_lex::optimize_unflattened_subqueries (this=0x7e7d500182d8, const_only=false) at /src/mariadb2/sql/sql_lex.cc:5073

#18 0x000060e18d23643c in JOIN::optimize_unflattened_subqueries (this=0x7e7d5001ca00) at /src/mariadb2/sql/opt_subselect.cc:5907

#19 0x000060e18d008bb9 in JOIN::optimize_stage2 (this=0x7e7d5001ca00) at /src/mariadb2/sql/sql_select.cc:3344

#20 0x000060e18d0067c3 in JOIN::optimize_inner (this=0x7e7d5001ca00) at /src/mariadb2/sql/sql_select.cc:2751

#21 0x000060e18d003a8b in JOIN::optimize (this=0x7e7d5001ca00) at /src/mariadb2/sql/sql_select.cc:2006

#22 0x000060e18d0105bb in mysql_select (thd=0x7e7d50000dc8, tables=0x7e7d5001b8b0, fields=..., conds=0x0, og_num=0, order=0x0, group=0x0, having=0x0, proc_param=0x0, select_options=2164525824, result=0x7e7d5001c9d8, unit=0x7e7d500053c0, select_lex=0x7e7d500182d8) at /src/mariadb2/sql/sql_select.cc:5370

#23 0x000060e18cffd590 in handle_select (thd=0x7e7d50000dc8, lex=0x7e7d500052e0, result=0x7e7d5001c9d8, setup_tables_done_option=0) at /src/mariadb2/sql/sql_select.cc:634

#24 0x000060e18cf9d0d7 in execute_sqlcom_select (thd=0x7e7d50000dc8, all_tables=0x7e7d5001b8b0) at /src/mariadb2/sql/sql_parse.cc:6166

#25 0x000060e18cf9488e in mysql_execute_command (thd=0x7e7d50000dc8, is_called_from_prepared_stmt=false) at /src/mariadb2/sql/sql_parse.cc:3954

#26 0x000060e18cfa22e8 in mysql_parse (thd=0x7e7d50000dc8, rawbuf=0x7e7d50018200 "SELECT md5(a) IN (SELECT * FROM (SELECT '' FROM t) as x) FROM t", length=63, parser_state=0x7e7d628e62c0) at /src/mariadb2/sql/sql_parse.cc:7882

#27 0x000060e18cf8db01 in dispatch_command (command=COM_QUERY, thd=0x7e7d50000dc8, packet=0x7e7d5000c159 "SELECT md5(a) IN (SELECT * FROM (SELECT '' FROM t) as x) FROM t", packet_length=63, blocking=true) at /src/mariadb2/sql/sql_parse.cc:1877

#28 0x000060e18cf8c3e6 in do_command (thd=0x7e7d50000dc8, blocking=true) at /src/mariadb2/sql/sql_parse.cc:1416

#29 0x000060e18d1a8826 in do_handle_one_connection (connect=0x60e1c6632278, put_in_cache=true) at /src/mariadb2/sql/sql_connect.cc:1414

#30 0x000060e18d1a859b in handle_one_connection (arg=0x60e1c660d1b8) at /src/mariadb2/sql/sql_connect.cc:1326

#31 0x000060e18d78a598 in pfs_spawn_thread (arg=0x60e1c66250c8) at /src/mariadb2/storage/perfschema/pfs.cc:2198

#32 0x00007e7d690a27f1 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:448

#33 0x00007e7d69133c9c in __GI___clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78