Bug #17499 Alter table of ndb partitioned tables causes mysqld to core

- moved used_partitions initialization

sql/ha_ndbcluster.cc

@@ -3381,8 +3381,13 @@ int ha_ndbcluster::extra(enum ha_extra_function operation)
     DBUG_PRINT("info", ("HA_EXTRA_RESET"));
     DBUG_PRINT("info", ("Clearing condition stack"));
     cond_clear();
+    /*
+     * Regular partition pruning will set the bitmap appropriately.
+     * Some queries like ALTER TABLE doesn't use partition pruning and
+     * thus the 'used_partitions' bitmap needs to be initialized
+     */
     if (m_part_info)
-      bitmap_clear_all(&m_part_info->used_partitions);
+      bitmap_set_all(&m_part_info->used_partitions);
     break;
   case HA_EXTRA_IGNORE_DUP_KEY:       /* Dup keys don't rollback everything*/
     DBUG_PRINT("info", ("HA_EXTRA_IGNORE_DUP_KEY"));

sql/sql_table.cc

@@ -5200,8 +5200,6 @@ copy_data_between_tables(TABLE *from,TABLE *to,
   */
   to->file->ha_set_all_bits_in_write_set();
   from->file->ha_retrieve_all_cols();
-  if (from->part_info)
-    bitmap_set_all(&(from->part_info->used_partitions));
   init_read_record(&info, thd, from, (SQL_SELECT *) 0, 1,1);
   if (ignore ||
       handle_duplicates == DUP_REPLACE)