select.test, sql_select.cc, sql_lex.cc, item.cc:

  Bug #7672 after merge fix

mysql-test/t/select.test

@@ -2165,7 +2165,7 @@ select found_rows();
 
 DROP TABLE t1;
 
-# End of 4.1 tests
+#
 # Bug 7672 Unknown column error in order clause
 #
 CREATE TABLE t1 (a INT, b INT);
@@ -2174,3 +2174,4 @@ CREATE TABLE t1 (a INT, b INT);
 SELECT a, b AS c FROM t1 ORDER BY c+1;
 SELECT a, b AS c FROM t1 ORDER BY b+1;
 drop table t1;
+# End of 4.1 tests

sql/item.cc

@@ -1760,10 +1760,15 @@ bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
     if ((tmp= find_field_in_tables(thd, this, tables, &where, 0)) ==
 	not_found_field)
     {
-      if (thd->lex.select_lex.is_item_list_lookup)
+      /* Look up in current select's item_list to find aliased fields */
+      if (thd->lex->current_select->is_item_list_lookup)
       {
-        Item** res= find_item_in_list(this, thd->lex.select_lex.item_list);
-        if (res && *res && (*res)->type() == Item::FIELD_ITEM)
+        uint counter;
+        bool not_used;
+        Item** res= find_item_in_list(this, thd->lex->current_select->item_list,
+                                      &counter, REPORT_EXCEPT_NOT_FOUND,
+                                      &not_used);
+        if (res != not_found_item && (*res)->type() == Item::FIELD_ITEM)
         {
           set_field((*((Item_field**)res))->field);
           return 0;

sql/sql_lex.cc

@@ -160,7 +160,6 @@ void lex_start(THD *thd, uchar *buf,uint length)
   lex->duplicates= DUP_ERROR;
   lex->ignore= 0;
   lex->proc_list.first= 0;
-  lex->select_lex.is_item_list_lookup= 0;
 }
 
 void lex_end(LEX *lex)
@@ -1084,6 +1083,7 @@ void st_select_lex::init_query()
   prep_where= 0;
   subquery_in_having= explicit_limit= 0;
   parsing_place= NO_MATTER;
+  is_item_list_lookup= 0;
 }
 
 void st_select_lex::init_select()
@@ -1110,6 +1110,7 @@ void st_select_lex::init_select()
   select_limit= HA_POS_ERROR;
   offset_limit= 0;
   with_sum_func= 0;
+
 }
 
 /*

sql/sql_select.cc

@@ -8348,11 +8348,16 @@ find_order_in_list(THD *thd, Item **ref_pointer_array,
 
     'it' reassigned in if condition because fix_field can change it.
   */
+  thd->lex->current_select->is_item_list_lookup= 1;
   if (!it->fixed &&
       (it->fix_fields(thd, tables, order->item) ||
        (it= *order->item)->check_cols(1) ||
        thd->is_fatal_error))
+  {
+    thd->lex->current_select->is_item_list_lookup= 0;
     return 1;					// Wrong field 
+  }
+  thd->lex->current_select->is_item_list_lookup= 0;
   uint el= all_fields.elements;
   all_fields.push_front(it);		        // Add new field to field list
   ref_pointer_array[el]= it;