Uncaught Error: Cannot pass parameter 4 by reference

$qry = "insert into feed_info (site_url, feed_xml_url, enabled) values (?,?,?)";
$stmt->bind_param('sss', $obj["site_url"], $obj["feed_xml_url"],0);

This was the PHP code that threw this exception.

Uncaught Error: Cannot pass parameter 4 by reference

PHP error: “Cannot pass parameter 2 by reference” The pass by value 0 caused the issue, when the method is expecting a variable / pass by reference.

The following code fixed the problem.

$enabled=0;
$stmt->bind_param('sss', $obj["site_url"], $obj["feed_xml_url"],$enabled);