Posted by Jerry Stuckle on 07/30/07 21:21

google2006@sensation.net.au wrote:
> The following code never sees the end of the array, and generates an
> out of memory error under PHP5 (both CLI and Apache module) :
>
> while (isset($rank[$i])) {
> $rank[$i] = trim($rank[$i++]);
> }
>
> Moving the post increment to a separate line fixes this issue:
>
> while (isset($rank[$i])) {
> $rank[$i] = trim($rank[$i]);
> $i++;
> }
>
> For some reason PHP5 appears to be initializing $rank[($i+1)] each
> time, perhaps because it's passing the value to trim(). The subsequent
> isset() test on that element succeeds so the loop continues
> indefinitely as each new element is initialized.
>
> It works as expected under PHP4, stopping once it hits the end of the
> array. I can't find any documentation which hints at any change to the
> handling of uninitialized variables which caused this code to break.
>
> Thanks in advance for any help...
>

I did a quick look and don't see where this was behavior was explicitly
changed, but it looks more like a bug to me.

$i++ returns the old value of $i, so $rank[$i + 1] should never be
evaluated, IMHO.

I'd suggest putting it up as a bug on php.net and see what they say
about it.

--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
==================

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