(<5.4) E_ALL = E_ACTUALLY_ALL & ~E_STRICT
Fixed as of PHP 5.4.
E_ALL doesn't actually mean "E_ALL"; it means E_ACTUALLY_ALL & ~E_STRICT. Shouldn't it be named E_ALMOST_ALL instead? Why isn't there a real E_ALL named constant? (There is no real constant named E_ACTUALLY_ALL; however, in some situations it is possible to use -1 to mean the same thing.)