Packed keys: assertion failure

--source include/have_sequence.inc

--source include/have_innodb.inc

CREATE TABLE `t3` (

  `a` varchar(100) DEFAULT NULL,

  `b` varchar(32) DEFAULT NULL,

  `c` int(11) DEFAULT NULL

) ENGINE=INNODB DEFAULT CHARSET=utf8;

insert into t3 

select

  concat('1234567890AB-', 10000 + seq),

  concat('abcd-', 10000 + seq),

  NULL

from seq_1_to_10000;

set sort_buffer_size=32000;

select a from t3 order by a;

drop table t3;

Thread 14 "mysqld" received signal SIGABRT, Aborted.

[Switching to Thread 0x7ffff0057700 (LWP 28493)]

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

51      ../sysdeps/unix/sysv/linux/raise.c: No such file or directory.

(gdb) wher

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

#1  0x00007ffff56bd801 in __GI_abort () at abort.c:79

#2  0x00007ffff56ad39a in __assert_fail_base (fmt=0x7ffff58347d8 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x555556ce0080 "sort_length <= param->sort_length", file=file@entry=0x555556cdfa88 "/home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/filesort.cc", line=line@entry=1738, 

    function=function@entry=0x555556ce0ca0 <read_to_buffer(st_io_cache*, Merge_chunk*, Sort_param*)::__PRETTY_FUNCTION__> "ulong read_to_buffer(IO_CACHE*, Merge_chunk*, Sort_param*)") at assert.c:92

#3  0x00007ffff56ad412 in __GI___assert_fail (assertion=0x555556ce0080 "sort_length <= param->sort_length", file=0x555556cdfa88 "/home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/filesort.cc", line=1738, 

    function=0x555556ce0ca0 <read_to_buffer(st_io_cache*, Merge_chunk*, Sort_param*)::__PRETTY_FUNCTION__> "ulong read_to_buffer(IO_CACHE*, Merge_chunk*, Sort_param*)") at assert.c:101

#4  0x000055555611f5ee in read_to_buffer (fromfile=0x7ffff0055140, buffpek=0x7fffb8088da0, param=0x7ffff00550a0) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/filesort.cc:1738

#5  0x0000555556120619 in merge_buffers (param=0x7ffff00550a0, from_file=0x7ffff0055140, to_file=0x7fffb815d9c0, sort_buffer=..., lastbuff=0x7fffb8088d30, Fb=0x7fffb8088d30, Tb=0x7fffb8088da0, flag=1) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/filesort.cc:2087

#6  0x00005555561207a6 in merge_index (param=0x7ffff00550a0, sort_buffer=..., buffpek=0x7fffb8088d30, maxbuffer=2, tempfile=0x7ffff0055140, outfile=0x7fffb815d9c0) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/filesort.cc:2112

#7  0x000055555611b2fe in filesort (thd=0x7fffb8000d60, table=0x7fffb8159960, filesort=0x7fffb8016a88, tracker=0x7fffb8017160, join=0x7fffb8014cf8, first_table_bit=1) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/filesort.cc:389

#8  0x0000555555e6762a in create_sort_index (thd=0x7fffb8000d60, join=0x7fffb8014cf8, tab=0x7fffb8015f78, fsort=0x7fffb8016a88) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/sql_select.cc:23696

#9  0x0000555555e617da in st_join_table::sort_table (this=0x7fffb8015f78) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/sql_select.cc:21435

#10 0x0000555555e613b5 in join_init_read_record (tab=0x7fffb8015f78) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/sql_select.cc:21374

#11 0x0000555555e5f172 in sub_select (join=0x7fffb8014cf8, join_tab=0x7fffb8015f78, end_of_records=false) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/sql_select.cc:20451

#12 0x0000555555e5e662 in do_select (join=0x7fffb8014cf8, procedure=0x0) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/sql_select.cc:19992

#13 0x0000555555e32cbf in JOIN::exec_inner (this=0x7fffb8014cf8) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/sql_select.cc:4457

#14 0x0000555555e31deb in JOIN::exec (this=0x7fffb8014cf8) at /home/psergey/dev-git2/10.5-packed-sort-keys-cl/sql/sql_select.cc:4238

#15 0x0000555555e3351c in mysql_select (thd=0x7fffb8000d60, tables=0x7fffb8013b38, fields=..., conds=0x0, og_num=1, order=0x7fffb8014b70, group=0x0, having=0x0, proc_param=0x0, select_options=2147748608, result=0x7fffb8014cd0, unit=0x7fffb8004ca8, select_lex=0x7fffb8013538)

(gdb) list

1733            {

1734              uint sort_length=  param->using_packed_sortkeys() ?

1735                                 Sort_keys::read_sortkey_length(record) :

1736                                 param->sort_length;

1737

1738              DBUG_ASSERT(sort_length <= param->sort_length);

1739

1740              if (record + sort_length + size_of_addon_length >

1741                  buffpek->buffer_end())

1742                break;                                // Incomplete record.

(gdb) p sort_length

$1 = 360330348

(gdb) p param->sort_length

$2 = 307