Test showing that time() can be earlier than \DateTime() despite later in execution order

time-datetime-test.php

<?php

for ($tries = 0; $tries < 500000; ++$tries) {
    $first = (int)((new \DateTime('now'))->format('U'));
    $second = \time();

    if ($second < $first) {
	die("The second time was earlier after $tries tries:\n"
	    . "     First: $first\n"
	    . "    Second: $second\n");
    }
}