Fix WeakMap object reference offset causing TypeError

[Nevay]

Fix TypeError when using object reference as WeakMap offset.

$a = new stdClass();
$b = &$a;
$map = new WeakMap();
$map[$a] = true;

Fatal error: Uncaught TypeError: WeakMap key must be an object

[cmb69]

Thank you! That looks about right, although I don't quite understand the use case (why referencing an object?)

[Nevay]

I stumbled across this while using a by-ref parameter which is stored in a WeakMap afterwards (ref-1, ref-2):

function doStuff(?object &$obj = null): void {
    $obj = new stdClass();
}
doStuff($obj);
$map = new WeakMap();
$map[$obj] = null;

[cmb69]

Ah, yeah, that makes sense (although I wish PHP had out parameters for such purposes).

[arnaud-lb]

Thank you !