note 101990 added to datetime.diff

I found that DateTime::diff isn't as accurate as I thought. I calculated the age gap between now and a birthdate from before 1970 (unix epoch). Here's what I got: Given today is January 21st, 2011: <?php date_default_timezone_set('Europe/Berlin'); // birthdate format is YYYY-MM-DD $birth = new DateTime('1966-01-21'); $today = new DateTime(); $diff = $birth->diff($today); echo $diff->format('%y'); // will output 45 wrongly $birth = new DateTime('1966-01-23'); $today = new DateTime(); $diff = $birth->diff($today); echo $diff->format('%y'); // will output 45 wrongly $birth = new DateTime('1966-01-24'); // three days difference! $today = new DateTime(); $diff = $birth->diff($today); echo $diff->format('%y'); // will output 44 - correct ?> When calculating with the date() function it was more accurate (didn't use seconds/hours for comparison). Note that 3 days may be a lot if you want to create invoices and have to check against a given age to determine if the customer is chargable for taxes and so on. If someone also found this behaviour I'd like to hear about it - give me a quick mail at schindhelm (at) gmail (dot) com. Thanks. ---- Server IP: 69.147.83.197 Probable Submitter: 94.217.26.85 ---- Manual Page -- http://www.php.net/manual/en/datetime.diff.php Edit -- https://master.php.net/note/edit/101990 Del: integrated -- https://master.php.net/note/delete/101990/integrated Del: useless -- https://master.php.net/note/delete/101990/useless Del: bad code -- https://master.php.net/note/delete/101990/bad+code Del: spam -- https://master.php.net/note/delete/101990/spam Del: non-english -- https://master.php.net/note/delete/101990/non-english Del: in docs -- https://master.php.net/note/delete/101990/in+docs Del: other reasons-- https://master.php.net/note/delete/101990 Reject -- https://master.php.net/note/reject/101990 Search -- https://master.php.net/manage/user-notes.php