ID:               30695
 Updated by:       [EMAIL PROTECTED]
 Reported By:      php_bug at cklowe dot com
-Status:           Open
+Status:           Feedback
 Bug Type:         Math related
 Operating System: Win32
 PHP Version:      4CVS-2004-11-05 (stable)
 New Comment:

>This is *not* a signed/unsigned integer problem 
No, why? It is.
And it can be clearly seen in this example:
<?
define ("BIG_NUM", 0x80000000);
$big_var = 0x80000000;
printf("%u, %u\n", BIG_NUM, $big_var);
printf("%f, %f\n", BIG_NUM, $big_var);
?>

Overflown integers are treated as floats and you cannot use bitwise
operators on floats (as I understand you use them to check access
privileges).


Previous Comments:
------------------------------------------------------------------------

[2004-11-10 18:37:48] php_bug at cklowe dot com

This is a change in behaviour.  In version 4.3.8 (for example) the
expected result is displayed.  In the snapshot of a week ago, the
actual result was displayed.

This is *not* a signed/unsigned integer problem (sorry if my
description was unclear).  It is an initialization from a numeric
literal problem.  Saturation to 0x7fffffff should not occur.  If you
like, 0x80000000 should be treated as -2147483648.  Having (say)
0x80000000 treated as any ther value than 0x80000000 is surely wrong.

Forgive me for reopening this bug, but I fear I must.

------------------------------------------------------------------------

[2004-11-10 18:16:01] [EMAIL PROTECTED]

Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to report
a bug at http://bugs.php.net/how-to-report.php

PHP does not support unsigned integers.


------------------------------------------------------------------------

[2004-11-05 18:35:57] php_bug at cklowe dot com

Description:
------------
Large integers are being saturated to the maximum signed value
(0x7fffffff) as opposed to being treated as the unsigned values.  

Panic!  I had code that set the high bit in a Permissions variable when
some condition was met.  

After changing PHP versions because of bug 25570, I found user reports
of "Why have I got all these additional permissions?" and "I've now got
Admin rights, OOoooh.  What happens if I run this SQL query in the page
I now have access to?".

Reproduce code:
---------------
define ("BIG_NUM", 0x80000000);
$big_var = 0x80000000;
echo sprintf("%08x, %08x", BIG_NUM, $big_var);


Expected result:
----------------
80000000,80000000

Actual result:
--------------
7fffffff, 7fffffff


------------------------------------------------------------------------


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