Bug #76038 [Nab]: strtotime returning wrong date on -1 month

Edit report at https://bugs.php.net/bug.php?id=76038&edit=1 ID: 76038 Updated by: requinix@php.net Reported by: diego at agudo dot eti dot br Summary: strtotime returning wrong date on -1 month Status: Not a bug Type: Bug Package: Date/time related Operating System: Windows / Linux PHP Version: 7.2.2 Block user comment: N Private report: N New Comment: Good for them. But PHP and much of the Linux/GNU world do not work like that. Previous Comments: ------------------------------------------------------------------------ [2018-03-01 16:20:44] diego at agudo dot eti dot br Sorry but I disagree, should be 2018-02-28. Oracle/PostgreSQL/MySQL works like a charm. If I do like you said, I lost 2~3 days. SAMPLE MySQL: SELECT DATE_ADD(DATE_ADD(NOW(),INTERVAL + 30 DAY), INTERVAL -1 MONTH) ORACLE: SELECT ADD_MONTHS(TO_DATE('2018-03-31','YYYY-MM-DD'),-1) FROM DUAL ------------------------------------------------------------------------ [2018-03-01 15:32:00] requinix@php.net -1 month means subtract one from the month number. 2018-03-31 -1 month = 2018-02-31 which overflows to 2018-03-03. ------------------------------------------------------------------------ [2018-03-01 15:03:13] Wes dot example at example dot org I don't see how the suggested behavior is more correct than the current one. When doing "month math" you are supposed to ignore the days, since months have different lengths. ------------------------------------------------------------------------ [2018-03-01 14:28:13] diego at agudo dot eti dot br Description: ------------ strtotime returning wrong date on -1 month Test script: --------------- $data = '2018-03-31'; print_r($data); echo "\n\n"; $data = strtotime($data); print_r($data); echo "\n\n"; $data = date("Y-m-d", $data); print_r($data); echo "\n\n"; $data = strtotime($data); print_r($data); echo "\n\n"; $data = date("Y-m-d", strtotime('-1 month', $data)); print_r($data); echo "\n\n"; Expected result: ---------------- 2018-02-28 Actual result: -------------- 2018-03-03 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=76038&edit=1