Assertion `!derived->first_select()->first_inner_unit() || derived->first_select()->first_inner_unit()->with_element || derived->first_select()->first_inner_unit()->first_select()-> exclude_from_table_unique_test' failed

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 0 = (@A := `i`))) dt;

mysqld: /10.2/sql/table.cc:5638: 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.

190522 21:49:49 [ERROR] mysqld got signal 6 ;

stdlib/abort.c:91(__GI_abort)[0x7ff3de96002a]

assert/assert.c:92(__assert_fail_base)[0x7ff3de956bd7]

/lib/x86_64-linux-gnu/libc.so.6(+0x2dc82)[0x7ff3de956c82]

sql/table.cc:5640(TABLE_LIST::set_check_materialized())[0x55cd271e9307]

sql/table.h:2361(TABLE_LIST::set_materialized_derived())[0x55cd26e779c9]

sql/item_func.cc:4726(Item_func_set_user_var::fix_fields(THD*, Item**))[0x55cd2766b312]

sql/item_func.cc:200(Item_func::fix_fields(THD*, Item**))[0x55cd2763a5ca]

sql/sql_select.cc:1354(JOIN::optimize_inner())[0x55cd26ff53a6]

sql/sql_select.cc:1116(JOIN::optimize())[0x55cd26ff2d8d]

sql/sql_derived.cc:897(mysql_derived_optimize(THD*, LEX*, TABLE_LIST*))[0x55cd26eee59b]

sql/sql_derived.cc:198(mysql_handle_single_derived(LEX*, TABLE_LIST*, unsigned int))[0x55cd26eea74c]

sql/sql_select.cc:1402(JOIN::optimize_inner())[0x55cd26ff5b54]

sql/sql_select.cc:1116(JOIN::optimize())[0x55cd26ff2d8d]

sql/sql_union.cc:957(st_select_lex_unit::optimize())[0x55cd27195894]

sql/sql_derived.cc:888(mysql_derived_optimize(THD*, LEX*, TABLE_LIST*))[0x55cd26eee478]

sql/sql_derived.cc:198(mysql_handle_single_derived(LEX*, TABLE_LIST*, unsigned int))[0x55cd26eea74c]

sql/sql_select.cc:1402(JOIN::optimize_inner())[0x55cd26ff5b54]

sql/sql_select.cc:1116(JOIN::optimize())[0x55cd26ff2d8d]

sql/sql_select.cc:3806(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*))[0x55cd2700c2f5]

sql/sql_select.cc:376(handle_select(THD*, LEX*, select_result*, unsigned long))[0x55cd26febbd5]

sql/sql_parse.cc:6486(execute_sqlcom_select(THD*, TABLE_LIST*))[0x55cd26f73671]

sql/sql_parse.cc:3534(mysql_execute_command(THD*))[0x55cd26f60a66]

sql/sql_parse.cc:8020(mysql_parse(THD*, char*, unsigned int, Parser_state*, bool, bool))[0x55cd26f7bdd5]

sql/sql_parse.cc:1835(dispatch_command(enum_server_command, THD*, char*, unsigned int, bool, bool))[0x55cd26f5745f]

sql/sql_parse.cc:1387(do_command(THD*))[0x55cd26f545dc]

sql/sql_connect.cc:1335(do_handle_one_connection(CONNECT*))[0x55cd2727dc28]

sql/sql_connect.cc:1242(handle_one_connection)[0x55cd2727d630]

perfschema/pfs.cc:1864(pfs_spawn_thread)[0x55cd2842d544]

/lib/x86_64-linux-gnu/libpthread.so.0(+0x76ba)[0x7ff3df59b6ba]

x86_64/clone.S:111(clone)[0x7ff3dea3041d]

Query (0x62b000000288): select * from (select 1 from v1  union (select 1 from v1 where 0 = (@A := `i`))) dt