correction: 

the following code caused PHP to crash (for obvious reasons):

<?
$str = "foobar";
$hash = ord($str[0]);

/* .. rest of has value computation code ... */
?>


Well, I guess PHP could say something like: "dont use the variable name "hash" please... use your imagination to find another one :) "

Sorry, again a correction:

the problem was NOT the ord() function, but rather that PHP will not cope with large integers (even below 2^31).
Maybe the problem was the modulo operator and large numbers.
I will reprint my original source here:


function hash($str) {
// $p = 4294967291;        /* largest prime <= 2^32 */
// $p = 2147483647;        /* largest prime <= 2^31 */
// $p = 1073741789;        /* largest prime <= 2^30 */
// $p = 268435399;        /* largest prime <= 2^28 */
   $p = 33554393 ;        /* largest prime <= 2^25 */
// $p = 65521;            /* largest prime <= sqrt(2^32) */
  $BASE = 256;            /* largest char */

  if ($str == -1) {
    return -1;
  }

  $len = strlen($str);
  $hash = ord($str[0]);

  for ($i = 1; $i < $len; $i++) {
    debug("i = $i");
    $hash = (($hash * 32) + ord($str[$i])) % $p;
    debug("hash = $hash");
  }
  return $hash;
}

----
you can see from the values for $p some kind of boundary where the arithmetic ops wont work anymore. 
The debug() function basically echos the given string parameter. so nothing special about that.

Unfortunately I cannot change the name of the PR anymore but still please keep me informed what I can do to work with large numbers.

thanks,
aaron.

my mistake ... arghhh
sorry
(25 bits + 8 bit > 32 bit boundary)
Still, would be nice to have a "error: overflow message" :)