Bug #77243 [Ver->Csd]: Weekdays are calculated incorrectly for negative years

Edit report at https://bugs.php.net/bug.php?id=77243&edit=1 ID: 77243 Updated by: git@php.net Reported by: bjoern dot fischer at dezem dot de Summary: Weekdays are calculated incorrectly for negative years -Status: Verified +Status: Closed Type: Bug Package: Date/time related Operating System: Linux PHP Version: 7.2.12 Assigned To: derick Block user comment: N Private report: N New Comment: Automatic comment on behalf of derickr Revision: https://github.com/php/php-src/commit/36990aab8eda82984d4c9c7ddaeb2c131b31382c Log: Fixed bug #77243 (Weekdays are calculated incorrectly for negative years) Previous Comments: ------------------------------------------------------------------------ [2022-06-09 15:59:04] derick@php.net https://github.com/php/php-src/pull/8740 ------------------------------------------------------------------------ [2022-05-13 16:10:32] derick@php.net Dan and Christoph are both incorrect. PHP implements the ISO8601 calendar, which is the Gregorian calendar with the year 0. It supports timestamps in a 64-bit range, which is well beyond 1900 (like 213 billion years or so). This indeed looks like a bug. ------------------------------------------------------------------------ [2021-10-01 17:11:24] cmb@php.net Related To: Bug #78496 ------------------------------------------------------------------------ [2020-10-17 13:52:46] cmb@php.net > Expected: 0000-01-02 There is no year zero in the Gregorian nor the Julian calendar, though. Consider to use ext/calendar for such purposes. ------------------------------------------------------------------------ [2018-12-05 15:41:23] danack@php.net From the date page http://php.net/manual/en/function.date.php : The valid range of a timestamp is typically from Fri, 13 Dec 1901 20:45:54 GMT to Tue, 19 Jan 2038 03:14:07 GMT. (These are the dates that correspond to the minimum and maximum values for a 32-bit signed integer). However, before PHP 5.1.0 this range was limited from 01-01-1970 to 19-01-2038 on some systems (e.g. Windows). You may need to use a more specific library to cope with BCE dates, and to do things like deal with the Julian to Gregorian calendar changes. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=77243 -- Edit this bug report at https://bugs.php.net/bug.php?id=77243&edit=1