note 89146 added to language.operators.bitwise

I had a weird problem with bitwise operators applied to session variables in $_SESSION. I would check whether a logged user was authorized to perform an operation through a simple comparison between the bitmask of auth levels authorized for the operation and the user's auth level stored in $_SESSION: <?php $ok = ($allowed_auth & $_SESSION['auth']); ?> However, this got any sort of wrong and unpredictable results! In the end, I decided that something had to be going wrong with the way the PHP interpreter understood this operation, and I tried to typecast the session variable... et voilà: <?php $ok = ($allowed_auth & ((int) $_SESSION['auth'])); ?> This works perfectly. Bottom line: unless this is a bug that has been fixed in recent versions of PHP, you should typecast session variables to int before performing bitwise operations on them. ---- Server IP: 80.241.173.254 Probable Submitter: 84.220.166.138 ---- Manual Page -- http://www.php.net/manual/en/language.operators.bitwise.php Edit -- https://master.php.net/note/edit/89146 Del: integrated -- https://master.php.net/note/delete/89146/integrated Del: useless -- https://master.php.net/note/delete/89146/useless Del: bad code -- https://master.php.net/note/delete/89146/bad+code Del: spam -- https://master.php.net/note/delete/89146/spam Del: non-english -- https://master.php.net/note/delete/89146/non-english Del: in docs -- https://master.php.net/note/delete/89146/in+docs Del: other reasons-- https://master.php.net/note/delete/89146 Reject -- https://master.php.net/note/reject/89146 Search -- https://master.php.net/manage/user-notes.php