Re: Rethinking 64bit sizes and PHP-NG

On Sat, May 17, 2014 at 9:01 PM, Nikita Nefedov <inefedor@gmail.com> wrote: > Hey, > > First thank you for arranging all this points. > > I just wanted to ask: could we also make nNextFreeElement be unsigned? > Because with your proposal it would be possible to overflow it with the > code like this: $array[pow(2, 32) + 1] = 123; (if I understand it correctly) > > And besides that we can't have negative keys anyway. > PHP arrays store integral keys larger than PHP_INT_MAX as a string rather than an integer. Auto-incrementing does not work past that point. If you write something like this... $array[PHP_INT_MAX] = 42; $array[] = 43; ...you'll receive an error (this is intentional). You get that error because the code explicitly makes sure that nNextFreeElement can never overflow. (Here is an example of such an overflow check: http://lxr.php.net/xref/PHP_TRUNK/Zend/zend_hash.c#435). Nikita