PHP Interger Overflow Handling Help

[davlee]

I'm having problems running a php program on my Linux box which runs fine on my Windows box.

 

I traced the problem down to a line of code:

 

$higherValue = 0xFFFFFFFF;

 

This should be an maximum unsigned int value of 4294967295, but PHP doesn't handle unsigned int so it should convert it to a float. This is not happening on my system. Instead it is just converting it to a max int value of 2147483647.

 

I wrote a small php test script:

 

var_dump(0x00000000);

var_dump(0xFFFFFFFF);

var_dump(0xFFFFFFFE);

 

On Windows:

 

int(0)

float(4294967295)

float(4294967294)

 

On Linux:

 

int(0)

int(2147483647)

int(2147483647)

 

Versions:

 

Windows:

 

>.\win32\php -c php-win.ini -v

PHP 5.3.15 (cli) (built: Jul 20 2012 00:20:38)

Copyright © 1997-2012 The PHP Group

Zend Engine v2.3.0, Copyright © 1998-2012 Zend Technologies

 

Linux:

> php -v

PHP 5.3.27 (cli) (built: Jun 24 2014 01:48:44)

Copyright © 1997-2013 The PHP Group

Zend Engine v2.3.0, Copyright © 1998-2013 Zend Technologies

 

 

How do I get integer overflow working? Do I have a bad build of PHP?

[mikosiko]

In your Linux Box what echo PHP_INT_MAX produce?

 

from the manual

The size of an integer is platform-dependent, although a maximum value of about two billion is the usual value (that's 32 bits signed). 64-bit platforms usually have a maximum value of about 9E18, except for Windows, which is always 32 bit. PHP does not support unsigned integers. Integer size can be determined using the constant PHP_INT_SIZE, and maximum value using the constant PHP_INT_MAX since PHP 4.4.0 and PHP 5.0.5.

 

[davlee]

Size = 4, Max = 2147483647