#27533 [Opn->Csd]: gmmktime can return wrong value on the night that DST comes into affect

ID: 27533 Updated by: rasmus@php.net Reported By: scottmacvicar at ntlworld dot com -Status: Open +Status: Closed Bug Type: Date/time related Operating System: * PHP Version: 4CVS, 5CVS (2004-03-11) New Comment: This bug has been fixed in CVS. Snapshots of the sources are packaged every three hours; this change will be in the next snapshot. You can grab the snapshot at http://snaps.php.net/. Thank you for the report, and for helping us make PHP better. Previous Comments: ------------------------------------------------------------------------ [2004-03-12 12:10:16] rasmus@php.net On my Linux box with TZ set to GMT I get: 1080259200 - 26 1080345600 - 27 1080432000 - 28 1080518400 - 29 which appears to me to be correct. But if this patch works around the bug on Windows then I don't see any problem with it. I don't see how it could negatively impact other platforms. ------------------------------------------------------------------------ [2004-03-09 09:44:15] webmaster at panyopanyo dot com I too can confirm this occurs on my system which uses the clock settings described here ------------------------------------------------------------------------ [2004-03-09 09:41:52] webmaster at ragnarokonline dot de wfm with my local timezone (Germany, GMT+1) but I could reproduce it, after I've changed the timzone to GMT+0 (Dublin, Edinburgh, Lissabon, London) Autodetect DST-Settings was always active. ------------------------------------------------------------------------ [2004-03-08 21:27:34] scottmacvicar at ntlworld dot com Description: ------------ This bug seems to have different affect on Windows and Linux. Windows ------ System has to be running GMT and Automatically adjust clock for daylight savings time checked. You'll notice that the 27th appears twice. The second occurence of the 27th is Sat Mar 27 23:00:00 2004. ------ Redhat 9.0 ------ The timestamp for linux on the 28th is Sun Mar 28 02:00:00 2004 /etc/sysconfig/clock ZONE="Europe/London" UTC=true ARC=false ------ So Windows lost an hour and linux gained 2 hours. Patch --- datetime.c 2004-03-09 02:19:32.000000000 +0000 +++ datetime.c.patched 2004-03-09 02:20:48.000000000 +0000 @@ -192,8 +192,8 @@ /* fall-through */ case 1: /* hour */ val = (*arguments[0])->value.lval; - if (val < 1) { - chgsecs += (1-val) * 60*60; val = 1; + if (val < 2) { + chgsecs += (2-val) * 60*60; val = 2; } ta->tm_hour = val; /* fall-through */ Changing the time to 02:01:01 seems to correct this issue and the windows machine stops eating an hour and not setting tm_idst to 1 and i have no idea whats going on with the linux machine. Reproduce code: --------------- <?php for ($i = 26; $i <= 29; $i++) { $datestamp = gmmktime(0, 0, 0, 3, $i, 2004); $day = gmdate('j', $datestamp); echo "$datestamp - $day\n\n"; } ?> Expected result: ---------------- 1080259200 - 26 1080345600 - 27 1080432000 - 28 1080518400 - 29 Actual result: -------------- Windows --- 1080259200 - 26 1080345600 - 27 1080428400 - 27 1080518400 - 29 Linux --- 1080259200 - 26 1080345600 - 27 1080439200 - 28 1080518400 - 29 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=27533&edit=1