#30271 [Com]: Bitwise operator returns unwanted values

From: Date: Mon, 25 Oct 2004 07:30:53 +0000
Subject: #30271 [Com]: Bitwise operator returns unwanted values
References: 1  Groups: php.bugs 
Request: Send a blank email to php-bugs+get-68042@lists.php.net to get a copy of this message 
 ID:               30271
 Comment by:       one_half at seznam dot cz
 Reported By:      mccohy at kyberdigi dot cz
 Status:           Wont fix
 Bug Type:         Math related
 Operating System: Linux
 PHP Version:      5.0.2
 New Comment:

And what about to retype it to 64-bit integer ? :)) Or is that
difficult ?? :))


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

[2004-10-23 20:51:23] hholzgra@php.net

-2147483649 is to big for a PHP int so it is actually treated as a
float,
and the behavior of & on floats is undefined

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

[2004-10-18 00:18:37] almekind at xs4all dot nl

In php 5.0.1 it was still OK. Came with 5.0.2

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

[2004-09-29 10:17:53] mccohy at kyberdigi dot cz

Description:
------------
The bitwise operator "and" returns an unwanted value. Here is a simple
example:

Let's store value 924303769 in variable $a and value -2147483649 in
variable $ax. Now, let's count the 'bitwise and' of these two variables
($a & $ax).

PHP 5.0.2 returns zero. PHP 4.3.9 returns 924303769. I am not sure what
happens in 5.0.0 or 5.0.1, sorry.


Reproduce code:
---------------
$a=924303769;
$ax=-2147483649;
echo ($a & $ax)."\n"; 


Expected result:
----------------
924303769

Actual result:
--------------
0


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


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