PHP get last month in March bug

This post is not laravel related, but is a big bug in PHP regarding how it handles months, especially February.

If you need  the last month, today(March 29), with one of the following ways

 date('Y-m-d', strtotime('-1 Month'));

 date('Y-m-d', mktime(0,0,0,date("m")-1,date("d"),date("Y")) );

 $date = new DateTime();
 $date->modify("-1 Month");

They all return “2013-03-01”, which can screw up your applications big time.

The solution is:

 date('Y-m-d', strtotime('first day of last month'));

Which returns “2013-02-01”;