- don't call JOIN::join_free(1) twice for every join in JOIN::cleanup().

The reason it happened was that both, JOIN::cleanup() and JOIN::join_free(),
went over all nested joins and called cleanup/join_free for them.
For that:
- split recursive and non-recursive parts of JOIN::cleanup() and
JOIN::join_free()
- rename JOIN::cleanup to JOIN::destroy, as it actually destroys its
  argument
- move the recursive part of JOIN::cleanup to st_select_lex::cleanup
- move the non-recursive part of JOIN::join_free to the introduced
  method JOIN::cleanup().

1 files changed, 29 insertions, 21 deletions

diff --git a/sql/sql_union.cc b/sql/sql_union.cc
index f59d7fffe85..87b67a5127a 100644
--- a/sql/sql_union.cc
+++ b/sql/sql_union.cc
@@ -553,7 +553,6 @@ bool st_select_lex_unit::exec()
 bool st_select_lex_unit::cleanup()
 {
   int error= 0;
-  JOIN *join;
   DBUG_ENTER("st_select_lex_unit::cleanup");
 
   if (cleaned)
@@ -572,29 +571,17 @@ bool st_select_lex_unit::cleanup()
   }
 
   for (SELECT_LEX *sl= first_select_in_union(); sl; sl= sl->next_select())
+    error|= sl->cleanup();
+
+  if (fake_select_lex)
   {
-    if ((join= sl->join))
-    {
-      error|= sl->join->cleanup();
-      delete join;
-    }
-    else
+    JOIN *join;
+    if ((join= fake_select_lex->join))
     {
-      // it can be DO/SET with subqueries
-      for (SELECT_LEX_UNIT *lex_unit= sl->first_inner_unit();
-	   lex_unit != 0;
-	   lex_unit= lex_unit->next_unit())
-      {
-	error|= lex_unit->cleanup();
-      }
+      join->tables_list= 0;
+      join->tables= 0;
     }
-  }
-  if (fake_select_lex && (join= fake_select_lex->join))
-  {
-    join->tables_list= 0;
-    join->tables= 0;
-    error|= join->cleanup();
-    delete join;
+    error|= fake_select_lex->cleanup();
   }
 
   DBUG_RETURN(error);
@@ -650,3 +637,24 @@ bool st_select_lex_unit::change_result(select_subselect *result,
     res= fake_select_lex->join->change_result(result);
   return (res);
 }
+
+
+bool st_select_lex::cleanup()
+{
+  bool error= FALSE;
+  DBUG_ENTER("st_select_lex::cleanup()");
+
+  if (join)
+  {
+    error|= join->destroy();
+    delete join;
+    join= 0;
+  }
+  for (SELECT_LEX_UNIT *lex_unit= first_inner_unit(); lex_unit ;
+       lex_unit= lex_unit->next_unit())
+  {
+    error|= lex_unit->cleanup();
+  }
+  DBUG_RETURN(error);
+}
+