SIGSEGV in Item_field::Item_field on plugin aggregate DISTINCT over a constant

INSTALL SONAME 'func_test';

SELECT test_plugin_count(DISTINCT 1);

Core was generated by `/test/mtest/MDEV-40672/MD130926-mariadb-13.2.0-linux-x86_64-dbg/bin/mariadbd --'.

Program terminated with signal SIGSEGV, Segmentation fault.

#0  0x00005824a07469f8 in Item_field::Item_field (this=0x76b65401c170, thd=0x76b654000d60, f=0x0)at /test/mtest/MDEV-40672/13.1_dbg/sql/item.cc:3348

[Current thread is 1 (LWP 1698251)]

(gdb) bt

#0  0x00005824a07469f8 in Item_field::Item_field (this=0x76b65401c170, thd=0x76b654000d60, f=0x0)at /test/mtest/MDEV-40672/13.1_dbg/sql/item.cc:3348

#1  0x00005824a08795c1 in Aggregator_distinct::setup (this=0x76b65401bfd0, thd=0x76b654000d60) at /test/mtest/MDEV-40672/13.1_dbg/sql/item_sum.cc:844

#2  0x00005824a03848b5 in Item_sum::aggregator_setup (this=0x76b65401abe0, thd=0x76b654000d60) at /test/mtest/MDEV-40672/13.1_dbg/sql/item_sum.h:560

#3  0x00005824a0337c0d in setup_sum_funcs (thd=0x76b654000d60, func_ptr=0x76b65401bfa8)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_select.cc:30241

#4  0x00005824a0333fc7 in JOIN::make_aggr_tables_info (this=0x76b65401b6f0)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_select.cc:4238

#5  0x00005824a0322491 in JOIN::optimize_stage2 (this=0x76b65401b6f0)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_select.cc:3618

#6  0x00005824a031fca6 in JOIN::optimize_inner (this=0x76b65401b6f0)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_select.cc:2790

#7  0x00005824a031d44d in JOIN::optimize (this=0x76b65401b6f0)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_select.cc:2017

#8  0x00005824a0315038 in mysql_select (thd=0x76b654000d60, tables=0x0, fields=@0x76b65401a838: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x76b65401ad10, last = 0x76b65401ad10, elements = 1}, <No data fields>}, conds=0x0, og_num=0, order=0x0, group=0x0, having=0x0, proc_param=0x0, select_options=2164525824, result=0x76b65401b6c0, unit=0x76b6540052f8, select_lex=0x76b65401a580)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_select.cc:5426

#9  0x00005824a0314bc5 in handle_select (thd=0x76b654000d60, lex=0x76b654005218, result=0x76b65401b6c0, setup_tables_done_option=0)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_select.cc:637

#10 0x00005824a02b105d in execute_sqlcom_select (thd=0x76b654000d60, all_tables=0x0) at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_parse.cc:6266

#11 0x00005824a02a5b86 in mysql_execute_command (thd=0x76b654000d60, is_called_from_prepared_stmt=false)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_parse.cc:4038

#12 0x00005824a029dbe4 in mysql_parse (thd=0x76b654000d60, rawbuf=0x76b65401a4d0 "SELECT test_plugin_count(DISTINCT 1)", length=36, parser_state=0x7eb7450b5a80)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_parse.cc:8005

#13 0x00005824a029afad in dispatch_command (command=COM_QUERY, thd=0x76b654000d60, packet=0x76b65400b701 "SELECT test_plugin_count(DISTINCT 1)", packet_length=36, blocking=true)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_parse.cc:1903

#14 0x00005824a029e793 in do_command (thd=0x76b654000d60, blocking=true)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_parse.cc:1437

#15 0x00005824a04a5039 in do_handle_one_connection (connect=0x5824dbe8e390, put_in_cache=true)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_connect.cc:1514

#16 0x00005824a04a4dde in handle_one_connection (arg=0x5824dbf77bc0)at /test/mtest/MDEV-40672/13.1_dbg/sql/sql_connect.cc:1426

#17 0x00007eb76c69cb84 in start_thread (arg=<optimized out>)at ./nptl/pthread_create.c:447

#18 0x00007eb76c729ecc in clone3 ()at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78