What potential issues can arise when switching from non-SSL to SSL during a session in PHP?

When switching from non-SSL to SSL during a session in PHP, potential issues can arise due to the session cookie being marked as secure. This can lead to session invalidation or loss of session data. To solve this issue, you can override the session cookie settings to ensure it is not marked as secure when switching to SSL.

// Override session cookie settings to prevent marking as secure
ini_set('session.cookie_secure', 0);