ID: 31569
User updated by: php at milonic dot com
Reported By: php at milonic dot com
Status: Open
Bug Type: Math related
Operating System: Fedora/Linux 9
PHP Version: 4.3.10
New Comment:
Narrowed the problem down to this:
$b=251066875;
$a=-3111919630;
echo $b ^= ($a<<10);
Fedora 3 echos: 251066875 (wrong)
All other OS's echo: 25768443 (correct)
Maybe it helps?
Cheers
Andy
Previous Comments:
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[2005-01-16 14:34:27] php at milonic dot com
Sorry but it's still the same even with 4.3.11-DEV
My guess is that this could be a Fedora problem but would like to know
either way.
It also seems unrelated to PHP version, happens on all of them both 4
and 5 - It all points to Fedora but just cannot think how.
I'll dig a little deeper and let you know if I find anything
Cheers
Andy
------------------------------------------------------------------------
[2005-01-16 13:05:15] [EMAIL PROTECTED]
Please try using this CVS snapshot:
http://snaps.php.net/php4-STABLE-latest.tar.gz
For Windows:
http://snaps.php.net/win32/php4-win32-STABLE-latest.zip
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[2005-01-16 12:59:15] php at milonic dot com
Description:
------------
Values returned using the following code produce different results
(incorrect) in PHP-4.3.10 and PHP-4.3.9 on Fedora Core 3.
When the same code is executed on a Linux 9 or FreeBSD5.3 machine the
values are correct.
Could be a Fedora problem but thought you'd like to take a look.
Reproduce code:
---------------
<?
function fillZeros($a, $b){
$z = hexdec(80000000);
if ($z & $a){
$a = ($a>>1);
$a &= (~$z);
$a |= 0x40000000;
$a = ($a>>($b-1));
}
else{
$a = ($a>>$b);
}
return $a;
}
function mixture($a,$b,$c)
{
$a -= $b; $a -= $c; $a ^= (fillZeros($c,13));
$b -= $c; $b -= $a; $b ^= ($a<<8);
$c -= $a; $c -= $b; $c ^= (fillZeros($b,13));
$a -= $b; $a -= $c; $a ^= (fillZeros($c,12));
$b -= $c; $b -= $a; $b ^= ($a<<16);
$c -= $a; $c -= $b; $c ^= (fillZeros($b,5));
$a -= $b; $a -= $c; $a ^= (fillZeros($c,3));
$b -= $c; $b -= $a; $b ^= ($a<<10);
$c -= $a; $c -= $b; $c ^= (fillZeros($b,15));
return array($a,$b,$c);
}
$test= mixture("11", "22", "33");
echo "$test[0], $test[1], $test[2]\n";
?>
Expected result:
----------------
Should be:
251066875, -1654377486, -1500734959
Actual result:
--------------
But instead get:
251066875, 1541925888, -402039036
Only happens on Fedora, all other boxes are fine.
------------------------------------------------------------------------
--
Edit this bug report at http://bugs.php.net/?id=31569&edit=1
