php is even more crappy than i thought

crap.php

<?php
error_reporting(E_ALL|E_STRICT);

function crap(&$var) {
    echo '$var='.$var."\n";
    $var = 'x';
}

crap($x = 123);
# Strict Standards: Only variables should be passed by reference in php shell code on line 1
echo '$x='.$x."\n";
# 123
crap($y);
echo '$y='.$y."\n";
# x

gistfile1.txt

Output:

Strict Standards: Only variables should be passed by reference in - on line 9
$var=123
$x=123
$var=
$y=x