I am working on a login system for a project using MVC programming and ran into this error. Here is the code, the problem line is #31
This login system is a tutoria
The problem is that the 3rd parameter is the result of a function call:
md5($pass . $this->salt)
You need to save that value to a variable before passing it to bind_param so that it can be passed by reference.
Example:
$password = md5($pass . $this->salt);
$stmt->bind_param("ss", $user, $password);
Also, don't use md5 to hash passwords.