Warning: parameter by reference

I get the following warning:
Warning: Parameter 1 to bodyclasses_bodyclasses_user_role() expected to be a reference, value given in bodyclasses_get_bodyclasses() (line 81 of /var/www/html/hyper/sites/all/modules/contrib/bodyclasses/bodyclasses.module).

none of the callback functions use the $variables to alter any values
thus they do not need to receive the variable via reference

function bodyclasses_bodyclasses_user_role(&$variables) {
function bodyclasses_bodyclasses_context(&$variables) {
function bodyclasses_bodyclasses_views(&$variables) {

instead be just

function bodyclasses_bodyclasses_user_role($variables) {
function bodyclasses_bodyclasses_context($variables) {
function bodyclasses_bodyclasses_views($variables) {