PHP notice: Undefined variable: source

Undefined variable: source in field_file_save_file() (field_file.inc)

  if (!file_copy($file, $file->destination, FILE_EXISTS_RENAME)) {
    form_set_error($source, t('File upload error. Could not move uploaded file.'));
    watchdog('file', 'Upload error. Could not move file %file to destination %destination.', array('%file' => $file->filename, '%destination' => $file->filepath));
    return 0;
  }

$source should be changed to $file->source
and $file->filepath should be changed to $file->destination