MDEV-21998: Server crashes in st_select_lex::add_table_to_list upon mix of KILL and sequences

Continue support the hack of current select equal builtin select if
selects stack is empty even after subselects.

mysql-test/main/parser.result

@@ -1893,4 +1893,12 @@ i
 1
 i
 2
+#
+# MDEV-21998: Server crashes in st_select_lex::add_table_to_list
+# upon mix of KILL and sequences
+#
+KILL ( SELECT 1 ) + LASTVAL(s);
+ERROR 42000: KILL does not support subqueries or stored functions
+KILL LASTVAL(s);
+ERROR 42000: KILL does not support subqueries or stored functions
 # End of 10.4 tests

mysql-test/main/parser.test

@@ -1677,6 +1677,14 @@ $$
 
 DELIMITER ;$$
 
+--echo #
+--echo # MDEV-21998: Server crashes in st_select_lex::add_table_to_list
+--echo # upon mix of KILL and sequences
+--echo #
 
+--error ER_SUBQUERIES_NOT_SUPPORTED
+KILL ( SELECT 1 ) + LASTVAL(s);
+--error ER_SUBQUERIES_NOT_SUPPORTED
+KILL LASTVAL(s);
 
 --echo # End of 10.4 tests

mysql-test/main/signal.result

@@ -2285,13 +2285,13 @@ begin
 DECLARE foo CONDITION FOR SQLSTATE '12345';
 SIGNAL foo SET MYSQL_ERRNO = `65`; /* illegal */
 end $$
-ERROR 42S22: Unknown column '65' in 'field list'
+ERROR 42000: Undeclared variable: 65
 create procedure test_signal()
 begin
 DECLARE foo CONDITION FOR SQLSTATE '12345';
 SIGNAL foo SET MYSQL_ERRNO = `A`; /* illegal */
 end $$
-ERROR 42S22: Unknown column 'A' in 'field list'
+ERROR 42000: Undeclared variable: A
 create procedure test_signal()
 begin
 DECLARE foo CONDITION FOR SQLSTATE '12345';
@@ -2342,7 +2342,7 @@ DECLARE foo CONDITION FOR SQLSTATE '12345';
 SIGNAL foo SET MYSQL_ERRNO = 1000,
 MESSAGE_TEXT = `Hello`;
 end $$
-ERROR 42S22: Unknown column 'Hello' in 'field list'
+ERROR 42000: Undeclared variable: Hello
 create procedure test_signal()
 begin
 DECLARE foo CONDITION FOR SQLSTATE '12345';

mysql-test/main/signal.test

@@ -2546,7 +2546,7 @@ end $$
 call test_signal $$
 drop procedure test_signal $$
 
--- error ER_BAD_FIELD_ERROR
+-- error ER_SP_UNDECLARED_VAR
 create procedure test_signal()
 begin
   DECLARE foo CONDITION FOR SQLSTATE '12345';
@@ -2554,7 +2554,7 @@ begin
 end $$
 
 
--- error ER_BAD_FIELD_ERROR
+-- error ER_SP_UNDECLARED_VAR
 create procedure test_signal()
 begin
   DECLARE foo CONDITION FOR SQLSTATE '12345';
@@ -2616,7 +2616,7 @@ end $$
 call test_signal $$
 drop procedure test_signal $$
 
--- error ER_BAD_FIELD_ERROR
+-- error ER_SP_UNDECLARED_VAR
 create procedure test_signal()
 begin
   DECLARE foo CONDITION FOR SQLSTATE '12345';

mysql-test/main/sp-error.result

@@ -454,7 +454,7 @@ else
 set b = a;
 end if;
 end|
-ERROR 42S22: Unknown column 'aa' in 'field list'
+ERROR 42000: Undeclared variable: aa
 create procedure bug4344() drop procedure bug4344|
 ERROR HY000: Can't drop or alter a PROCEDURE from within another stored routine
 create procedure bug4344() drop function bug4344|
@@ -1069,7 +1069,7 @@ IF bug13037_foo THEN
 SELECT 1;
 END IF;
 END|
-ERROR 42S22: Unknown column 'bug13037_foo' in 'field list'
+ERROR 42000: Undeclared variable: bug13037_foo
 CREATE PROCEDURE bug13037_p2()
 BEGIN
 SET @bug13037_foo = bug13037_bar;

mysql-test/main/sp-error.test

@@ -615,7 +615,7 @@ call bug2653_1(1, @b)|
 
 drop procedure bug2653_1|
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug2653_2(a int, out b int)
 begin
   if aa < 0 then
@@ -1508,7 +1508,7 @@ DROP PROCEDURE IF EXISTS bug13037_p3;
 
 delimiter |;
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 CREATE PROCEDURE bug13037_p1()
 BEGIN
   IF bug13037_foo THEN

mysql-test/main/sp.result

@@ -4186,7 +4186,7 @@ select v, isnull(v);
 end if;
 end;
 end|
-ERROR 42S22: Unknown column 'undefined_var' in 'field list'
+ERROR 42000: Undeclared variable: undefined_var
 create procedure bug14643_2()
 begin
 declare continue handler for sqlexception select 'boo' as 'Handler';
@@ -4198,7 +4198,7 @@ select 2;
 end case;
 select undefined_var;
 end|
-ERROR 42S22: Unknown column 'undefined_var' in 'field list'
+ERROR 42000: Undeclared variable: undefined_var
 drop procedure if exists bug14304|
 drop table if exists t3, t4|
 create table t3(a int primary key auto_increment)|
@@ -4228,7 +4228,7 @@ create procedure bug14376()
 begin
 declare x int default x;
 end|
-ERROR 42S22: Unknown column 'x' in 'field list'
+ERROR 42000: Undeclared variable: x
 create procedure bug14376()
 begin
 declare x int default 42;
@@ -4483,7 +4483,7 @@ select 'no' as 'v';
 end if;
 select 'done' as 'End';
 end|
-ERROR 42S22: Unknown column 'v' in 'field list'
+ERROR 42000: Undeclared variable: v
 create procedure bug14498_2()
 begin
 declare continue handler for sqlexception select 'error' as 'Handler';
@@ -4492,7 +4492,7 @@ select 'yes' as 'v';
 end while;
 select 'done' as 'End';
 end|
-ERROR 42S22: Unknown column 'v' in 'field list'
+ERROR 42000: Undeclared variable: v
 create procedure bug14498_3()
 begin
 declare continue handler for sqlexception select 'error' as 'Handler';
@@ -4501,7 +4501,7 @@ select 'maybe' as 'v';
 until v end repeat;
 select 'done' as 'End';
 end|
-ERROR 42S22: Unknown column 'v' in 'field list'
+ERROR 42000: Undeclared variable: v
 create procedure bug14498_4()
 begin
 declare continue handler for sqlexception select 'error' as 'Handler';
@@ -4515,7 +4515,7 @@ select '?' as 'v';
 end case;
 select 'done' as 'End';
 end|
-ERROR 42S22: Unknown column 'v' in 'field list'
+ERROR 42000: Undeclared variable: v
 create procedure bug14498_5()
 begin
 declare continue handler for sqlexception select 'error' as 'Handler';
@@ -4529,7 +4529,7 @@ select '?' as 'v';
 end case;
 select 'done' as 'End';
 end|
-ERROR 42S22: Unknown column 'v' in 'field list'
+ERROR 42000: Undeclared variable: v
 drop table if exists t3|
 drop procedure if exists bug15231_1|
 drop procedure if exists bug15231_2|
@@ -8403,7 +8403,7 @@ DECLARE name VARCHAR(10);
 SET name="hello";
 call p1(name2);
 END|
-ERROR 42S22: Unknown column 'name2' in 'field list'
+ERROR 42000: Undeclared variable: name2
 call p2();
 a
 hello

mysql-test/main/sp.test

@@ -5046,7 +5046,7 @@ drop procedure if exists bug14643_1|
 drop procedure if exists bug14643_2|
 --enable_warnings
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug14643_1()
 begin
   declare continue handler for sqlexception select 'boo' as 'Handler';
@@ -5062,7 +5062,7 @@ begin
   end;
 end|
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug14643_2()
 begin
   declare continue handler for sqlexception select 'boo' as 'Handler';
@@ -5117,7 +5117,7 @@ drop table t3, t4|
 drop procedure if exists bug14376|
 --enable_warnings
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug14376()
 begin
   declare x int default x;
@@ -5344,7 +5344,7 @@ drop procedure if exists bug14498_4|
 drop procedure if exists bug14498_5|
 --enable_warnings
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug14498_1()
 begin
   declare continue handler for sqlexception select 'error' as 'Handler';
@@ -5357,7 +5357,7 @@ begin
   select 'done' as 'End';
 end|
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug14498_2()
 begin
   declare continue handler for sqlexception select 'error' as 'Handler';
@@ -5368,7 +5368,7 @@ begin
   select 'done' as 'End';
 end|
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug14498_3()
 begin
   declare continue handler for sqlexception select 'error' as 'Handler';
@@ -5379,7 +5379,7 @@ begin
   select 'done' as 'End';
 end|
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug14498_4()
 begin
   declare continue handler for sqlexception select 'error' as 'Handler';
@@ -5395,7 +5395,7 @@ begin
   select 'done' as 'End';
 end|
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 create procedure bug14498_5()
 begin
   declare continue handler for sqlexception select 'error' as 'Handler';
@@ -9931,7 +9931,7 @@ BEGIN
   call p1(name);
 END|
 
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 CREATE OR REPLACE PROCEDURE p3 ()
 BEGIN
   DECLARE name VARCHAR(10);

mysql-test/suite/compat/oracle/r/sp-cursor-rowtype.result

@@ -1045,7 +1045,7 @@ NULL;
 END LOOP;
 END;
 $$
-ERROR 42000: Undefined CURSOR: c2
+ERROR 42000: Undeclared variable: c2
 # Make sure "rec" shadows other declarations outside the loop
 CREATE TABLE t1 (a INT, b VARCHAR(10));
 INSERT INTO t1 VALUES (10, 'b0');

mysql-test/suite/compat/oracle/r/sp.result

@@ -1019,7 +1019,7 @@ LOOP
 EXIT WHEN unknown_ident IS NULL;
 END LOOP;
 END$$
-ERROR 42S22: Unknown column 'unknown_ident' in 'field list'
+ERROR 42000: Undeclared variable: unknown_ident
 CREATE PROCEDURE p1
 AS
 BEGIN
@@ -1028,7 +1028,7 @@ LOOP
 EXIT label WHEN unknown_ident IS NULL;
 END LOOP;
 END$$
-ERROR 42S22: Unknown column 'unknown_ident' in 'field list'
+ERROR 42000: Undeclared variable: unknown_ident
 CREATE PROCEDURE p1
 AS
 BEGIN
@@ -1036,7 +1036,7 @@ LOOP
 CONTINUE WHEN unknown_ident IS NULL;
 END LOOP;
 END$$
-ERROR 42S22: Unknown column 'unknown_ident' in 'field list'
+ERROR 42000: Undeclared variable: unknown_ident
 CREATE PROCEDURE p1
 AS
 BEGIN
@@ -1045,7 +1045,7 @@ LOOP
 CONTINUE label WHEN unknown_ident IS NULL;
 END LOOP;
 END$$
-ERROR 42S22: Unknown column 'unknown_ident' in 'field list'
+ERROR 42000: Undeclared variable: unknown_ident
 #
 # MDEV-10583 sql_mode=ORACLE: SQL%ROWCOUNT
 #

mysql-test/suite/compat/oracle/t/sp-cursor-rowtype.test

@@ -1128,7 +1128,7 @@ DELIMITER ;$$
 --echo # IN followed by an unknown cursor name
 
 DELIMITER $$;
---error ER_SP_CURSOR_MISMATCH
+--error ER_SP_UNDECLARED_VAR
 CREATE PROCEDURE p1 AS
   CURSOR c1 IS SELECT 'test' AS a FROM DUAL;
 BEGIN

mysql-test/suite/compat/oracle/t/sp.test

@@ -1094,7 +1094,7 @@ DROP FUNCTION f1;
 --echo #
 
 DELIMITER $$;
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 CREATE PROCEDURE p1
 AS
 BEGIN
@@ -1106,7 +1106,7 @@ DELIMITER ;$$
 
 
 DELIMITER $$;
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 CREATE PROCEDURE p1
 AS
 BEGIN
@@ -1119,7 +1119,7 @@ DELIMITER ;$$
 
 
 DELIMITER $$;
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 CREATE PROCEDURE p1
 AS
 BEGIN
@@ -1131,7 +1131,7 @@ DELIMITER ;$$
 
 
 DELIMITER $$;
---error ER_BAD_FIELD_ERROR
+--error ER_SP_UNDECLARED_VAR
 CREATE PROCEDURE p1
 AS
 BEGIN

sql/sql_lex.cc

@@ -7560,6 +7560,7 @@ Item *LEX::create_item_ident_sp(THD *thd, Lex_ident_sys_st *name,
 
   const Sp_rcontext_handler *rh;
   sp_variable *spv;
+  uint unused_off;
   DBUG_ASSERT(spcont);
   DBUG_ASSERT(sphead);
   if ((spv= find_variable(name, &rh)))
@@ -7598,7 +7599,9 @@ Item *LEX::create_item_ident_sp(THD *thd, Lex_ident_sys_st *name,
       return new (thd->mem_root) Item_func_sqlerrm(thd);
   }
 
-  if (!current_select)
+  if (!select_stack_head() &&
+      (current_select->parsing_place != FOR_LOOP_BOUND ||
+       spcont->find_cursor(name, &unused_off, false) == NULL))
   {
     // we are out of SELECT or FOR so it is syntax error
     my_error(ER_SP_UNDECLARED_VAR, MYF(0), name->str);
@@ -9083,7 +9086,8 @@ Item *LEX::create_item_query_expression(THD *thd,
 
   // Add the subtree of subquery to the current SELECT_LEX
   SELECT_LEX *curr_sel= select_stack_head();
-  DBUG_ASSERT(current_select == curr_sel);
+  DBUG_ASSERT(current_select == curr_sel ||
+              (curr_sel == NULL && current_select == &builtin_select));
   if (!curr_sel)
   {
     curr_sel= &builtin_select;
@@ -9315,7 +9319,8 @@ SELECT_LEX *LEX::parsed_subselect(SELECT_LEX_UNIT *unit)
 
   // Add the subtree of subquery to the current SELECT_LEX
   SELECT_LEX *curr_sel= select_stack_head();
-  DBUG_ASSERT(current_select == curr_sel);
+  DBUG_ASSERT(current_select == curr_sel ||
+              (curr_sel == NULL && current_select == &builtin_select));
   if (curr_sel)
   {
     curr_sel->register_unit(unit, &curr_sel->context);
@@ -9391,7 +9396,8 @@ TABLE_LIST *LEX::parsed_derived_table(SELECT_LEX_UNIT *unit,
 
   // Add the subtree of subquery to the current SELECT_LEX
   SELECT_LEX *curr_sel= select_stack_head();
-  DBUG_ASSERT(current_select == curr_sel);
+  DBUG_ASSERT(current_select == curr_sel ||
+              (curr_sel == NULL && current_select == &builtin_select));
 
   Table_ident *ti= new (thd->mem_root) Table_ident(unit);
   if (ti == NULL)

sql/sql_lex.h

@@ -3632,8 +3632,9 @@ public:
 
     if (unlikely(!select_stack_top))
     {
-      current_select= NULL;
-      DBUG_PRINT("info", ("Top Select is empty"));
+      current_select= &builtin_select;
+      DBUG_PRINT("info", ("Top Select is empty -> sel builtin: %p",
+                          current_select));
     }
     else
       current_select= select_stack[select_stack_top - 1];