Manual merge of mysql-5.1-bugteam into mysql-trunk-merge.

Conflicts:

Text conflict in .bzr-mysql/default.conf
Text conflict in mysql-test/suite/rpl/r/rpl_slow_query_log.result
Text conflict in mysql-test/suite/rpl/t/rpl_slow_query_log.test
Conflict adding files to server-tools.  Created directory.
Conflict because server-tools is not versioned, but has versioned children.  Versioned directory.
Conflict adding files to server-tools/instance-manager.  Created directory.
Conflict because server-tools/instance-manager is not versioned, but has versioned children.  Versioned directory.
Contents conflict in server-tools/instance-manager/options.cc
Text conflict in sql/mysqld.cc

1 files changed, 22 insertions, 6 deletions

diff --git a/sql/item.cc b/sql/item.cc
index b52619ceee0..4b6b77860d6 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -4467,17 +4467,33 @@ bool Item_field::fix_fields(THD *thd, Item **reference)
               It's not an Item_field in the select list so we must make a new
               Item_ref to point to the Item in the select list and replace the
               Item_field created by the parser with the new Item_ref.
+
+              NOTE: If we are fixing an alias reference inside ORDER/GROUP BY
+              item tree, then we use new Item_ref as an intermediate value
+              to resolve referenced item only.
+              In this case the new Item_ref item is unused.
             */
             Item_ref *rf= new Item_ref(context, db_name,table_name,field_name);
             if (!rf)
               return 1;
-            thd->change_item_tree(reference, rf);
+
+            bool save_group_fix_field= thd->lex->current_select->group_fix_field;
             /*
-              Because Item_ref never substitutes itself with other items 
-              in Item_ref::fix_fields(), we can safely use the original 
-              pointer to it even after fix_fields()
-             */
-            return rf->fix_fields(thd, reference) ||  rf->check_cols(1);
+              No need for recursive resolving of aliases.
+            */
+            thd->lex->current_select->group_fix_field= 0;
+
+            bool ret= rf->fix_fields(thd, (Item **) &rf) || rf->check_cols(1);
+            thd->lex->current_select->group_fix_field= save_group_fix_field;
+            if (ret)
+              return TRUE;
+
+            if (save_group_fix_field && alias_name_used)
+              thd->change_item_tree(reference, *rf->ref);
+            else
+              thd->change_item_tree(reference, rf);
+
+            return FALSE;
           }
         }
       }