fixed cleupup() for distinct aggregate functions (BUG#2663)

sql/item_sum.cc:
  fixed cleupup() for distinct aggregate functions
tests/client_test.c:
  fixed subqueries test
  test of distinct aggregate functions in PS

sql/item_sum.cc

@@ -1093,13 +1093,18 @@ void Item_sum_count_distinct::cleanup()
   if (!original)
   {
     if (table)
+    {
       free_tmp_table(current_thd, table);
+      table= 0;
+    }
     delete tmp_table_param;
+    tmp_table_param= 0;
     if (use_tree)
+    {
       delete_tree(tree);
-    table= 0;
       use_tree= 0;
     }
+  }
   DBUG_VOID_RETURN;
 }
 
@@ -1677,10 +1682,17 @@ void Item_func_group_concat::cleanup()
   {
     THD *thd= current_thd;
     if (table)
+    {
       free_tmp_table(thd, table);
+      table= 0;
+    }
     delete tmp_table_param;
+    tmp_table_param= 0;
     if (tree_mode)
+    {
       delete_tree(tree);
+      tree_mode= 0;
+    }
   }
   DBUG_VOID_RETURN;
 }

tests/client_test.c

@@ -8117,6 +8117,7 @@ static void test_subqueries()
   myquery(rc);
 
   stmt= mysql_prepare(mysql, query, strlen(query));
+  mystmt_init(stmt);
   for (i= 0; i < 3; i++)
   {
     rc= mysql_execute(stmt);
@@ -8142,6 +8143,37 @@ static void test_bad_union()
   myerror(NULL); 
 }
 
+static void test_distinct()
+{
+  MYSQL_STMT *stmt;
+  int rc, i;
+  const char *query= "SELECT count(distinct b), group_concat(a) FROM t1";
+
+  myheader("test_subquery");
+  
+  rc = mysql_query(mysql, "DROP TABLE IF EXISTS t1");
+  myquery(rc);
+  
+  rc= mysql_query(mysql,"CREATE TABLE t1 (a int , b int);");
+  myquery(rc);
+
+  rc= mysql_query(mysql,
+		  "insert into t1 values (1,1), (2, 2), (3,3), (4,4), (5,5);");
+  myquery(rc);
+
+  for (i= 0; i < 3; i++)
+  {
+    stmt= mysql_prepare(mysql, query, strlen(query));
+    mystmt_init(stmt);
+    rc= mysql_execute(stmt);
+    mystmt(stmt, rc);
+    assert(1 == my_process_stmt_result(stmt));
+    mysql_stmt_close(stmt);
+  }
+
+  rc= mysql_query(mysql, "DROP TABLE t1");
+  myquery(rc);
+}
 
 /*
   Read and parse arguments and MySQL options from my.cnf
@@ -8390,6 +8422,7 @@ int main(int argc, char **argv)
                                prepared queries */
     test_subqueries();	    /* repeatable subqueries */
     test_bad_union();       /* correct setup of UNION */
+    test_distinct();	    /* distinct aggregate functions */
 
 
     end_time= time((time_t *)0);