ID: 30695
Updated by: [EMAIL PROTECTED]
Reported By: php_bug at cklowe dot com
Status: Open
Bug Type: Math related
Operating System: Win32
PHP Version: 4CVS-2004-11-05 (stable)
New Comment:
THis is a change most likely caused by Joe's patches to it. I say we
should revert it as it breaks too many scripts.
Previous Comments:
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[2004-11-10 19:30:11] php_bug at cklowe dot com
I see your point, and I'm happy that integers are unsigned.
What worries me is that large hex initialisers (>= 0x80000000) are not
doing their job.
This is a change in behaviour.
Python v 2.4 and above, uses Large Integers for 0x80000000 which seems
acceptable. In previous versions it did the Right Thing and treated
0x80000000 as -214783648. Bitwise operations work as expected.
PHP did the Right Thing in version 4.3.8. As of the current snapshot
it no longer does the Right Thing.
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[2004-11-10 18:59:13] [EMAIL PROTECTED]
>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).
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[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.
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[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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Edit this bug report at http://bugs.php.net/?id=30695&edit=1
