create table t1 (i int) engine=myisam; 

create algorithm=temptable view v1 as select * from t1 ;

select * from (select 1 from v1 union (select 1 from v1 where @a := uuid())) dt;

mysqld: /10.2/sql/table.cc:5637: void TABLE_LIST::set_check_materialized(): Assertion `!derived->first_select()->first_inner_unit() || derived->first_select()->first_inner_unit()->first_select()-> exclude_from_table_unique_test' failed.

stdlib/abort.c:91(__GI_abort)[0x7fc843736bd7]

assert/assert.c:92(__assert_fail_base)[0x7fc843736c82]

/10.2/sql/mysqld(_ZN10TABLE_LIST22set_check_materializedEv+0x2af)[0x55c67728514b]

/10.2/sql/mysqld(_ZN10TABLE_LIST24set_materialized_derivedEv+0x23f)[0x55c676f1597f]

sql/table.cc:5639(TABLE_LIST::set_check_materialized())[0x55c6777062e8]

sql/table.h:2360(TABLE_LIST::set_materialized_derived())[0x55c6770928c4]

sql/item_func.cc:4720(Item_func_set_user_var::fix_fields(THD*, Item**))[0x55c6770902ab]

sql/sql_select.cc:1353(JOIN::optimize_inner())[0x55c676f8c3f9]

sql/sql_select.cc:1115(JOIN::optimize())[0x55c676f885aa]

sql/sql_derived.cc:897(mysql_derived_optimize(THD*, LEX*, TABLE_LIST*))[0x55c677093072]

sql/sql_derived.cc:198(mysql_handle_single_derived(LEX*, TABLE_LIST*, unsigned int))[0x55c6770902ab]

sql/sql_select.cc:1401(JOIN::optimize_inner())[0x55c677231e04]

sql/sql_select.cc:1115(JOIN::optimize())[0x55c676f8c2d6]

sql/sql_union.cc:957(st_select_lex_unit::optimize())[0x55c676f885aa]

sql/sql_derived.cc:888(mysql_derived_optimize(THD*, LEX*, TABLE_LIST*))[0x55c677093072]

sql/sql_derived.cc:198(mysql_handle_single_derived(LEX*, TABLE_LIST*, unsigned int))[0x55c6770902ab]

sql/sql_select.cc:1401(JOIN::optimize_inner())[0x55c6770a978b]

sql/sql_select.cc:1115(JOIN::optimize())[0x55c67708913d]

sql/sql_select.cc:3804(mysql_select(THD*, TABLE_LIST*, unsigned int, List<Item>&, Item*, unsigned int, st_order*, st_order*, Item*, st_order*, unsigned long long, select_result*, st_select_lex_unit*, st_select_lex*))[0x55c677010aad]

sql/sql_select.cc:376(handle_select(THD*, LEX*, select_result*, unsigned long))[0x55c676ffdf73]

sql/sql_parse.cc:6479(execute_sqlcom_select(THD*, TABLE_LIST*))[0x55c677019211]

sql/sql_parse.cc:3537(mysql_execute_command(THD*))[0x55c676ff48c6]

sql/sql_parse.cc:8013(mysql_parse(THD*, char*, unsigned int, Parser_state*, bool, bool))[0x55c676ff1a45]

sql/sql_parse.cc:1834(dispatch_command(enum_server_command, THD*, char*, unsigned int, bool, bool))[0x55c6773199f6]

sql/sql_parse.cc:1386(do_command(THD*))[0x55c6773193fe]

sql/sql_connect.cc:1335(do_handle_one_connection(CONNECT*))[0x55c6784d1404]

/lib/x86_64-linux-gnu/libpthread.so.0(+0x76ba)[0x7fc84437b6ba]

x86_64/clone.S:111(clone)[0x7fc84381041d]