1--TEST-- 2call_user_func() in combination with "Call to a member function method() on a non-object" 3--FILE-- 4<?php 5$comparator= null; 6var_dump(call_user_func([$comparator, 'compare'], 1, 2)); 7echo "Alive\n"; 8?> 9--EXPECTF-- 10Warning: call_user_func() expects parameter 1 to be a valid callback, first array member is not a valid class name or object in %s on line %d 11NULL 12Alive 13 14