How can PHP version 5.4.5 impact the usage of certain functions like session_is_registered()?

In PHP version 5.4.5, the function session_is_registered() was deprecated and removed in later versions. To fix this issue, you should use the isset() function to check if a session variable is set instead.

// Before
if (session_is_registered('variable_name')) {
    // do something
}

// After
if (isset($_SESSION['variable_name'])) {
    // do something
}