Assertion `marked_for_read()' failed in Field_varstring::val_str on CHECKSUM TABLE

USE test;

SET SQL_MODE='';

CREATE TABLE t (v1 VARCHAR (255) AS (c1) PERSISTENT, c1 VARCHAR(50)) COLLATE=latin1_general_ci ENGINE=MyISAM;

INSERT INTO t VALUES(1,0xff00fef0);

CHECKSUM TABLE t EXTENDED;

mysqld: /test/10.5_dbg/sql/field.cc:7681: virtual String* Field_varstring::val_str(String*, String*): Assertion `marked_for_read()' failed.

Core was generated by `/test/MD150620-mariadb-10.5.4-linux-x86_64-dbg/bin/mysqld --no-defaults --core-'.

Program terminated with signal SIGABRT, Aborted.

#0  __pthread_kill (threadid=<optimized out>, signo=signo@entry=6)

    at ../sysdeps/unix/sysv/linux/pthread_kill.c:57

[Current thread is 1 (Thread 0x147aba8a2700 (LWP 1634674))]

(gdb) bt

#0  __pthread_kill (threadid=<optimized out>, signo=signo@entry=6) at ../sysdeps/unix/sysv/linux/pthread_kill.c:57

#1  0x0000555a824834c6 in my_write_core (sig=sig@entry=6) at /test/10.5_dbg/mysys/stacktrace.c:518

#2  0x0000555a81c25d60 in handle_fatal_signal (sig=6) at /test/10.5_dbg/sql/signal_handler.cc:330

#3  <signal handler called>

#4  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51

#5  0x0000147abb716801 in __GI_abort () at abort.c:79

#6  0x0000147abb70639a in __assert_fail_base (fmt=0x147abb88d7d8 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x555a8278a644 "marked_for_read()", file=file@entry=0x555a8278a473 "/test/10.5_dbg/sql/field.cc", line=line@entry=7681, function=function@entry=0x555a8278d140 <Field_varstring::val_str(String*, String*)::__PRETTY_FUNCTION__> "virtual String* Field_varstring::val_str(String*, String*)") at assert.c:92

#7  0x0000147abb706412 in __GI___assert_fail (assertion=assertion@entry=0x555a8278a644 "marked_for_read()", file=file@entry=0x555a8278a473 "/test/10.5_dbg/sql/field.cc", line=line@entry=7681, function=function@entry=0x555a8278d140 <Field_varstring::val_str(String*, String*)::__PRETTY_FUNCTION__> "virtual String* Field_varstring::val_str(String*, String*)") at assert.c:101

#8  0x0000555a81bff837 in Field_varstring::val_str (this=0x147a99852d30, val_buffer=<optimized out>, val_ptr=0x147aba8a0850) at /test/10.5_dbg/sql/field.cc:7681

#9  0x0000555a81c2e0d4 in Field::val_str (str=0x147aba8a0850, this=0x147a99852d30) at /test/10.5_dbg/sql/field.h:1025

#10 handler::calculate_checksum (this=0x147a998376a0) at /test/10.5_dbg/sql/handler.cc:5465

#11 0x0000555a81a46e4b in mysql_checksum_table (thd=thd@entry=0x147a99815088, tables=tables@entry=0x147a99874170, check_opt=check_opt@entry=0x147a9981a338) at /test/10.5_dbg/sql/sql_table.cc:11617

#12 0x0000555a8197c43d in mysql_execute_command (thd=thd@entry=0x147a99815088) at /test/10.5_dbg/sql/sql_parse.cc:4376

#13 0x0000555a8198815c in mysql_parse (thd=thd@entry=0x147a99815088, rawbuf=<optimized out>, length=<optimized out>, parser_state=parser_state@entry=0x147aba8a1350, is_com_multi=is_com_multi@entry=false, is_next_command=is_next_command@entry=false) at /test/10.5_dbg/sql/sql_parse.cc:7993

#14 0x0000555a81974c60 in dispatch_command (command=command@entry=COM_QUERY, thd=thd@entry=0x147a99815088, packet=packet@entry=0x147a99867089 "", packet_length=packet_length@entry=25, is_com_multi=is_com_multi@entry=false, is_next_command=is_next_command@entry=false) at /test/10.5_dbg/sql/sql_parse.cc:1874

#15 0x0000555a8197343a in do_command (thd=0x147a99815088) at /test/10.5_dbg/sql/sql_parse.cc:1355

#16 0x0000555a81acec47 in do_handle_one_connection (connect=<optimized out>, connect@entry=0x147a9cd7a808, put_in_cache=put_in_cache@entry=true) at /test/10.5_dbg/sql/sql_connect.cc:1411

#17 0x0000555a81acf363 in handle_one_connection (arg=arg@entry=0x147a9cd7a808) at /test/10.5_dbg/sql/sql_connect.cc:1313

#18 0x0000555a81f30902 in pfs_spawn_thread (arg=0x147aba046c88) at /test/10.5_dbg/storage/perfschema/pfs.cc:2201

#19 0x0000147abc3f96db in start_thread (arg=0x147aba8a2700) at pthread_create.c:463

#20 0x0000147abb7f788f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95