Recently I updated the PHP version of my site from 7.4 to 8 and found out that…
A date() working fine on PHP 7.4 and bringing today’s date without any date formatting, will throw an error on PHP 8:
Uncaught ArgumentCountError: date() expects at least 1 argument, 0
There is actually an easy fix for that, but it will break however your scripts.
So before updating to PHP 8, it might be a good idea searching your code for date() and correct it to at least
For a full list of changes between PHP 7.4.x and PHP 8.0.x just check the source.