1--TEST-- 2Omitting optional arg in method inherited from abstract class 3--FILE-- 4<?php 5 6abstract class A { 7 function foo($arg = 1) {} 8} 9 10class B extends A { 11 function foo() { 12 echo "foo\n"; 13 } 14} 15 16$b = new B(); 17$b->foo(); 18 19?> 20--EXPECTF-- 21Fatal error: Declaration of B::foo() must be compatible with A::foo($arg = 1) in %s on line %d 22