Fix for BUG#8218:

Remove TMP_TABLE_PARAM::copy_funcs_it. TMP_TABLE_PARAM is a member of JOIN which is 
copied via memcpy, and List_iterator_fast TMP_TABLE_PARAM::copy_funcs_it ends up 
pointing to the wrong List.


mysql-test/r/subselect.result:
  Testcase for BUG#8218
mysql-test/t/subselect.test:
  Testcase for BUG#8218
sql/sql_select.cc:
  Fix for BUG#8218: Create/use own iterator since TMP_TABLE_PARAM::copy_funcs_it is removed.

mysql-test/r/subselect.result

@@ -2196,3 +2196,110 @@ ERROR 42S22: Reference 'xx' not supported (forward reference in item list)
 select 1 = ALL (select 1 from t1 where 1 = xx ), 1 as xx from DUAL;
 ERROR 42S22: Reference 'xx' not supported (forward reference in item list)
 drop table t1;
+drop table if exists t1, t2, t3, t4, t5;
+Warnings:
+Note	1051	Unknown table 't1'
+Note	1051	Unknown table 't2'
+Note	1051	Unknown table 't3'
+Note	1051	Unknown table 't4'
+Note	1051	Unknown table 't5'
+CREATE TABLE t1 (
+categoryId int(11) NOT NULL,
+courseId int(11) NOT NULL,
+startDate datetime NOT NULL,
+endDate datetime NOT NULL,
+createDate datetime NOT NULL,
+modifyDate timestamp NOT NULL,
+attributes text NOT NULL
+);
+INSERT INTO t1 VALUES (1,41,'2004-02-09','2010-01-01','2004-02-09','2004-02-09',''),
+(1,86,'2004-08-16','2004-08-16','2004-08-16','2004-08-16',''),
+(1,87,'2004-08-16','2004-08-16','2004-08-16','2004-08-16',''),
+(2,52,'2004-03-15','2004-10-01','2004-03-15','2004-09-17',''),
+(2,53,'2004-03-16','2004-10-01','2004-03-16','2004-09-17',''),
+(2,88,'2004-08-16','2004-08-16','2004-08-16','2004-08-16',''),
+(2,89,'2004-08-16','2004-08-16','2004-08-16','2004-08-16',''),
+(3,51,'2004-02-09','2010-01-01','2004-02-09','2004-02-09',''),
+(5,12,'2004-02-18','2010-01-01','2004-02-18','2004-02-18','');
+CREATE TABLE t2 (
+userId int(11) NOT NULL,
+courseId int(11) NOT NULL,
+date datetime NOT NULL
+);
+INSERT INTO t2 VALUES (5141,71,'2003-11-18'),
+(5141,72,'2003-11-25'),(5141,41,'2004-08-06'),
+(5141,52,'2004-08-06'),(5141,53,'2004-08-06'),
+(5141,12,'2004-08-06'),(5141,86,'2004-10-21'),
+(5141,87,'2004-10-21'),(5141,88,'2004-10-21'),
+(5141,89,'2004-10-22'),(5141,51,'2004-10-26');
+CREATE TABLE t3 (
+groupId int(11) NOT NULL,
+parentId int(11) NOT NULL,
+startDate datetime NOT NULL,
+endDate datetime NOT NULL,
+createDate datetime NOT NULL,
+modifyDate timestamp NOT NULL,
+ordering int(11)
+);
+INSERT INTO t3 VALUES (12,9,'1000-01-01','3999-12-31','2004-01-29','2004-01-29',NULL);
+CREATE TABLE t4 (
+id int(11) NOT NULL,
+groupTypeId int(11) NOT NULL,
+groupKey varchar(50) NOT NULL,
+name text,
+ordering int(11),
+description text,
+createDate datetime NOT NULL,
+modifyDate timestamp NOT NULL
+);
+INSERT INTO t4 VALUES (9,5,'stationer','stationer',0,'Stationer','2004-01-29','2004-01-29'),
+(12,5,'group2','group2',0,'group2','2004-01-29','2004-01-29');
+CREATE TABLE t5 (
+userId int(11) NOT NULL,
+groupId int(11) NOT NULL,
+createDate datetime NOT NULL,
+modifyDate timestamp NOT NULL
+);
+INSERT INTO t5 VALUES (5141,12,'2004-08-06','2004-08-06');
+select
+count(distinct t2.userid) pass,
+groupstuff.*,
+count(t2.courseid) crse,
+t1.categoryid, 
+t2.courseid,
+date_format(date, '%b%y') as colhead
+from t2   
+join t1 on t2.courseid=t1.courseid  
+join
+(
+select 
+t5.userid,  
+parentid,  
+parentgroup,  
+childid,  
+groupname,  
+grouptypeid  
+from t5 
+join 
+(
+select t4.id as parentid,  
+t4.name as parentgroup,  
+t4.id as childid,  
+t4.name as groupname,  
+t4.grouptypeid  
+from   t4  
+) as gin on t5.groupid=gin.childid 
+) as groupstuff on t2.userid = groupstuff.userid 
+group by 
+groupstuff.groupname, colhead , t2.courseid;
+pass	userid	parentid	parentgroup	childid	groupname	grouptypeid	crse	categoryid	courseid	colhead
+1	5141	12	group2	12	group2	5	1	5	12	Aug04
+1	5141	12	group2	12	group2	5	1	1	41	Aug04
+1	5141	12	group2	12	group2	5	1	2	52	Aug04
+1	5141	12	group2	12	group2	5	1	2	53	Aug04
+1	5141	12	group2	12	group2	5	1	3	51	Oct04
+1	5141	12	group2	12	group2	5	1	1	86	Oct04
+1	5141	12	group2	12	group2	5	1	1	87	Oct04
+1	5141	12	group2	12	group2	5	1	2	88	Oct04
+1	5141	12	group2	12	group2	5	1	2	89	Oct04
+drop table if exists t1, t2, t3, t4, t5;

mysql-test/t/subselect.test

@@ -1465,3 +1465,105 @@ select 1 = ALL (select 1 from t1 where 1 = xx ), 1 as xx;
 -- error 1247
 select 1 = ALL (select 1 from t1 where 1 = xx ), 1 as xx from DUAL;
 drop table t1;
+
+# Test for BUG#8218
+drop table if exists t1, t2, t3, t4, t5;
+
+CREATE TABLE t1 (
+  categoryId int(11) NOT NULL,
+  courseId int(11) NOT NULL,
+  startDate datetime NOT NULL,
+  endDate datetime NOT NULL,
+  createDate datetime NOT NULL,
+  modifyDate timestamp NOT NULL,
+  attributes text NOT NULL
+);
+INSERT INTO t1 VALUES (1,41,'2004-02-09','2010-01-01','2004-02-09','2004-02-09',''),
+(1,86,'2004-08-16','2004-08-16','2004-08-16','2004-08-16',''),
+(1,87,'2004-08-16','2004-08-16','2004-08-16','2004-08-16',''),
+(2,52,'2004-03-15','2004-10-01','2004-03-15','2004-09-17',''),
+(2,53,'2004-03-16','2004-10-01','2004-03-16','2004-09-17',''),
+(2,88,'2004-08-16','2004-08-16','2004-08-16','2004-08-16',''),
+(2,89,'2004-08-16','2004-08-16','2004-08-16','2004-08-16',''),
+(3,51,'2004-02-09','2010-01-01','2004-02-09','2004-02-09',''),
+(5,12,'2004-02-18','2010-01-01','2004-02-18','2004-02-18','');
+
+CREATE TABLE t2 (
+  userId int(11) NOT NULL,
+  courseId int(11) NOT NULL,
+  date datetime NOT NULL
+);
+INSERT INTO t2 VALUES (5141,71,'2003-11-18'),
+(5141,72,'2003-11-25'),(5141,41,'2004-08-06'),
+(5141,52,'2004-08-06'),(5141,53,'2004-08-06'),
+(5141,12,'2004-08-06'),(5141,86,'2004-10-21'),
+(5141,87,'2004-10-21'),(5141,88,'2004-10-21'),
+(5141,89,'2004-10-22'),(5141,51,'2004-10-26');
+
+
+CREATE TABLE t3 (
+  groupId int(11) NOT NULL,
+  parentId int(11) NOT NULL,
+  startDate datetime NOT NULL,
+  endDate datetime NOT NULL,
+  createDate datetime NOT NULL,
+  modifyDate timestamp NOT NULL,
+  ordering int(11)
+);
+INSERT INTO t3 VALUES (12,9,'1000-01-01','3999-12-31','2004-01-29','2004-01-29',NULL);
+
+CREATE TABLE t4 (
+  id int(11) NOT NULL,
+  groupTypeId int(11) NOT NULL,
+  groupKey varchar(50) NOT NULL,
+  name text,
+  ordering int(11),
+  description text,
+  createDate datetime NOT NULL,
+  modifyDate timestamp NOT NULL
+);
+INSERT INTO t4 VALUES (9,5,'stationer','stationer',0,'Stationer','2004-01-29','2004-01-29'),
+(12,5,'group2','group2',0,'group2','2004-01-29','2004-01-29');
+
+CREATE TABLE t5 (
+  userId int(11) NOT NULL,
+  groupId int(11) NOT NULL,
+  createDate datetime NOT NULL,
+  modifyDate timestamp NOT NULL
+);
+INSERT INTO t5 VALUES (5141,12,'2004-08-06','2004-08-06');
+
+select
+  count(distinct t2.userid) pass,
+  groupstuff.*,
+  count(t2.courseid) crse,
+  t1.categoryid, 
+  t2.courseid,
+  date_format(date, '%b%y') as colhead
+from t2   
+join t1 on t2.courseid=t1.courseid  
+join
+(
+  select 
+    t5.userid,  
+    parentid,  
+    parentgroup,  
+    childid,  
+    groupname,  
+    grouptypeid  
+  from t5 
+  join 
+  (
+     select t4.id as parentid,  
+       t4.name as parentgroup,  
+       t4.id as childid,  
+       t4.name as groupname,  
+       t4.grouptypeid  
+     from   t4  
+  ) as gin on t5.groupid=gin.childid 
+) as groupstuff on t2.userid = groupstuff.userid 
+group by 
+  groupstuff.groupname, colhead , t2.courseid;
+
+drop table if exists t1, t2, t3, t4, t5;
+

sql/sql_class.h

@@ -1295,7 +1295,11 @@ class select_create: public select_insert {
 
 #include <myisam.h>
 
-/* Param to create temporary tables when doing SELECT:s */
+/* 
+  Param to create temporary tables when doing SELECT:s 
+  NOTE
+    This structure is copied using memcpy as a part of JOIN.
+*/
 
 class TMP_TABLE_PARAM :public Sql_alloc
 {
@@ -1307,7 +1311,6 @@ class TMP_TABLE_PARAM :public Sql_alloc
 public:
   List<Item> copy_funcs;
   List<Item> save_copy_funcs;
-  List_iterator_fast<Item> copy_funcs_it;
   Copy_field *copy_field, *copy_field_end;
   Copy_field *save_copy_field, *save_copy_field_end;
   byte	    *group_buff;
@@ -1324,7 +1327,7 @@ class TMP_TABLE_PARAM :public Sql_alloc
   uint  convert_blob_length; 
 
   TMP_TABLE_PARAM()
-    :copy_funcs_it(copy_funcs), copy_field(0), group_parts(0),
+    :copy_field(0), group_parts(0),
     group_length(0), group_null_parts(0), convert_blob_length(0)
   {}
   ~TMP_TABLE_PARAM()

sql/sql_select.cc

@@ -8601,8 +8601,7 @@ copy_fields(TMP_TABLE_PARAM *param)
   for (; ptr != end; ptr++)
     (*ptr->do_copy)(ptr);
 
-  List_iterator_fast<Item> &it=param->copy_funcs_it;
-  it.rewind();
+  List_iterator_fast<Item> it(param->copy_funcs);
   Item_copy_string *item;
   while ((item = (Item_copy_string*) it++))
     item->copy();