Bug #74914 [NEW]: DateInterval subtraction across daylight savings change is incorrect

From: ricjea at sbcglobal dot net Operating system: Windows Server 2012 PHP version: 5.6.31 Package: Date/time related Bug Type: Bug Bug description:DateInterval subtraction across daylight savings change is incorrect Description: ------------ Found in PHP 5.6.31, still exists in version 7 as per testing with https://3v4l.org/35D4t If you subtract a DateInterval that ends during the spring daylight savings time transition, the wrong DateTime and DateTime->getTimestamp() are returned. See example. If the DateInterval spans the full transition, then it is ok. Test script: --------------- $a = new \DateTime('2016-03-13 3:00:00', new DateTimeZone('America/Los_Angeles')); echo "Original Timestamp: ".$a->getTimeStamp()."\n"; $b = clone $a; $b->sub(new \DateInterval('PT1S')); echo "Subtract 1 second Timestamp: ".$b->getTimeStamp()."\n"; print_r([$a,$b]); Expected result: ---------------- Original Timestamp: 1457863200 Subtract 1 second Timestamp: 1457863199 Array ( [0] => DateTime Object ( [date] => 2016-03-13 03:00:00.000000 [timezone_type] => 3 [timezone] => America/Los_Angeles ) [1] => DateTime Object ( [date] => 2016-03-13 01:59:59.000000 [timezone_type] => 3 [timezone] => America/Los_Angeles ) ) Actual result: -------------- Original Timestamp: 1457863200 Subtract 1 second Timestamp: 1457866799 Array ( [0] => DateTime Object ( [date] => 2016-03-13 03:00:00.000000 [timezone_type] => 3 [timezone] => America/Los_Angeles ) [1] => DateTime Object ( [date] => 2016-03-13 03:59:59.000000 [timezone_type] => 3 [timezone] => America/Los_Angeles ) ) -- Edit bug report at https://bugs.php.net/bug.php?id=74914&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=74914&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=74914&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=74914&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=74914&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=74914&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=74914&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=74914&r=needscript Try newer version: https://bugs.php.net/fix.php?id=74914&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=74914&r=support Expected behavior: https://bugs.php.net/fix.php?id=74914&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=74914&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=74914&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=74914&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=74914&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=74914&r=dst IIS Stability: https://bugs.php.net/fix.php?id=74914&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=74914&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=74914&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=74914&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=74914&r=mysqlcfg