An other way to get all PHP errors that are set to be reported. This code will even work, when additional error types are added in future.
<?php
$pot = 0;
foreach (array_reverse(str_split(decbin(error_reporting()))) as $bit) {
if ($bit == 1) {
echo array_search(pow(2, $pot), get_defined_constants(true)['Core']). "<br>\n";
}
$pot++;
}
?>