Merge msvensson@bk-internal.mysql.com:/home/bk/mysql-5.0

into  devsrv-b.mysql.com:/users/msvensson/mysql-5.0

mysql-test/r/ps_11bugs.result

@@ -116,3 +116,17 @@ execute st_1676 using @arg0, @arg1, @arg2;
 cola	colb	cold
 aaaa	yyyy	R
 drop table t1, t2;
+create table t1 (a int primary key);
+insert into t1 values (1);
+explain select * from t1 where 3 in (select (1+1) union select 1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
+2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+3	DEPENDENT UNION	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+NULL	UNION RESULT	<union2,3>	ALL	NULL	NULL	NULL	NULL	NULL	
+select * from t1 where 3 in (select (1+1) union select 1);
+a
+prepare st_18492 from 'select * from t1 where 3 in (select (1+1) union select 1)';
+execute st_18492;
+a
+drop table t1;

mysql-test/r/subselect.result

@@ -744,7 +744,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 3	DEPENDENT UNION	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
 NULL	UNION RESULT	<union2,3>	ALL	NULL	NULL	NULL	NULL	NULL	
 Warnings:
-Note	1003	select `test`.`t2`.`id` AS `id` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`id`,<exists>(select 1 AS `Not_used` having (<cache>(`test`.`t2`.`id`) = <null_helper>(1)) union select 1 AS `Not_used` having (<cache>(`test`.`t2`.`id`) = <null_helper>(3))))
+Note	1003	select `test`.`t2`.`id` AS `id` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`id`,<exists>(select 1 AS `1` having (<cache>(`test`.`t2`.`id`) = <ref_null_helper>(1)) union select 3 AS `3` having (<cache>(`test`.`t2`.`id`) = <ref_null_helper>(3))))
 SELECT * FROM t2 WHERE id IN (SELECT 5 UNION SELECT 3);
 id
 SELECT * FROM t2 WHERE id IN (SELECT 5 UNION SELECT 2);

mysql-test/t/ps_11bugs.test

@@ -130,3 +130,17 @@ drop table t1, t2;
 # end of bug#1676
 
 # End of 4.1 tests
+
+# bug#18492: mysqld reports ER_ILLEGAL_REFERENCE in --ps-protocol
+
+create table t1 (a int primary key);
+insert into t1 values (1);
+
+explain select * from t1 where 3 in (select (1+1) union select 1);
+
+select * from t1 where 3 in (select (1+1) union select 1);
+
+prepare st_18492 from 'select * from t1 where 3 in (select (1+1) union select 1)';
+execute st_18492;
+
+drop table t1;

sql/item.cc

@@ -5151,14 +5151,6 @@ bool Item_direct_view_ref::eq(const Item *item, bool binary_cmp) const
   return FALSE;
 }
 
-void Item_null_helper::print(String *str)
-{
-  str->append(STRING_WITH_LEN("<null_helper>("));
-  store->print(str);
-  str->append(')');
-}
-
-
 bool Item_default_value::eq(const Item *item, bool binary_cmp) const
 {
   return item->type() == DEFAULT_VALUE_ITEM && 

sql/item.h

@@ -1849,21 +1849,6 @@ class Item_ref_null_helper: public Item_ref
   }
 };
 
-class Item_null_helper :public Item_ref_null_helper
-{
-  Item *store;
-public:
-  Item_null_helper(Name_resolution_context *context_arg,
-                   Item_in_subselect* master, Item *item,
-		   const char *table_name_arg, const char *field_name_arg)
-    :Item_ref_null_helper(context_arg, master, (store= 0, &store),
-                          table_name_arg, field_name_arg),
-     store(item)
-    { ref= &store; }
-  void print(String *str);
-};
-
-
 /*
   The following class is used to optimize comparing of date and bigint columns
   We need to save the original item ('ref') to be able to call

sql/item_subselect.cc

@@ -928,14 +928,14 @@ Item_in_subselect::single_value_transformer(JOIN *join,
   {
     Item *item= (Item*) select_lex->item_list.head();
 
-    select_lex->item_list.empty();
-    select_lex->item_list.push_back(new Item_int("Not_used",
-						 (longlong) 1, 21));
-    select_lex->ref_pointer_array[0]= select_lex->item_list.head();
     if (select_lex->table_list.elements)
     {
       bool tmp;
       Item *having= item, *orig_item= item;
+      select_lex->item_list.empty();
+      select_lex->item_list.push_back(new Item_int("Not_used",
+                                                   (longlong) 1, 21));
+      select_lex->ref_pointer_array[0]= select_lex->item_list.head();
       item= func->create(expr, item);
       if (!abort_on_null && orig_item->maybe_null)
       {
@@ -990,17 +990,15 @@ Item_in_subselect::single_value_transformer(JOIN *join,
 	  comparison functions can't be changed during fix_fields()
 	  we can assign select_lex->having here, and pass 0 as last
 	  argument (reference) to fix_fields()
-        */
-        item= func->create(expr,
-                           new Item_null_helper(&select_lex->context,
-                                                this, item,
-                                                (char *)"<no matter>",
-                                                (char *)"<result>"));
-#ifdef CORRECT_BUT_TOO_SLOW_TO_BE_USABLE
-        if (!abort_on_null && left_expr->maybe_null)
-          item= new Item_cond_or(new Item_func_isnull(left_expr), item);
-#endif
-	select_lex->having= join->having= item;
+	*/
+	select_lex->having=
+	  join->having=
+	  func->create(expr,
+                       new Item_ref_null_helper(&select_lex->context, this,
+                                            select_lex->ref_pointer_array,
+                                            (char *)"<no matter>",
+                                            (char *)"<result>"));
+
 	select_lex->having_fix_field= 1;
         /*
           we do not check join->having->fixed, because comparison function