From:             
Operating system: Fedora 14
PHP version:      5.3.6
Package:          *Programming Data Structures
Bug Type:         Bug
Bug description:Using $variable--; and $variable -= '1'; yield different 
results.

Description:
------------
While the code below may have other problems, the simple fact of the matter
is that when I uncomment "$int--;" and comment "$int -= '1';" the code will
loop for at least a minute, but when it is left as is below it does not and
will terminate as expected.  Since I've been told the two pieces of code
have the exact same logic, I have no explaination for this.  Please contact
me if you know why.  The php package was installed using 'yum install php
php-mysql' on fedora 14.







Test script:
---------------
<?php

function GeneratePassword($int, $string){

        $new_string = '';

        while ($int >= 0){

                $new_string += $string[rand(0, (strlen($string) - 1))];

                //$int--;

                $int -= '1';

                echo 'round';

                echo 'dump of int: ' . var_dump($int);

                echo 'dump of string: ' . var_dump($string);

                echo 'dump of new_string: ' . var_dump($new_string);

                

        }

        return ($new_string);

}



fwrite(STDOUT, "Choose an int");

$int = fgets(STDIN);

fwrite(STDOUT, "Choose a string");

$string = fgets(STDIN);

$pass = GeneratePassword($int, $string);

echo 'anything';

echo $pass;

?>

Actual result:
--------------
CASE 1 USING:

//$int--;

$int -= '1';

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



php -f delete_me2.php

Choose an int2

Choose a stringbb

roundint(1)

dump of int: string(3) "bb

"

dump of string: int(0)

dump of new_string: roundint(0)

dump of int: string(3) "bb

"

dump of string: int(0)

dump of new_string: roundint(-1)

dump of int: string(3) "bb

"

dump of string: int(0)

dump of new_string: anything0





CASE 2 USING:

$int--;

//$int -= '1';

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



php -f delete_me2.php

Choose an int2

Choose a stringbb

roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"

dump of int: string(3) "bb

"

dump of string: string(0) ""

dump of new_string: roundstring(2) "2

"



... (loops for at least 60 seconds) ...

-- 
Edit bug report at http://bugs.php.net/bug.php?id=54549&edit=1
-- 
Try a snapshot (PHP 5.2):            
http://bugs.php.net/fix.php?id=54549&r=trysnapshot52
Try a snapshot (PHP 5.3):            
http://bugs.php.net/fix.php?id=54549&r=trysnapshot53
Try a snapshot (trunk):              
http://bugs.php.net/fix.php?id=54549&r=trysnapshottrunk
Fixed in SVN:                        
http://bugs.php.net/fix.php?id=54549&r=fixed
Fixed in SVN and need be documented: 
http://bugs.php.net/fix.php?id=54549&r=needdocs
Fixed in release:                    
http://bugs.php.net/fix.php?id=54549&r=alreadyfixed
Need backtrace:                      
http://bugs.php.net/fix.php?id=54549&r=needtrace
Need Reproduce Script:               
http://bugs.php.net/fix.php?id=54549&r=needscript
Try newer version:                   
http://bugs.php.net/fix.php?id=54549&r=oldversion
Not developer issue:                 
http://bugs.php.net/fix.php?id=54549&r=support
Expected behavior:                   
http://bugs.php.net/fix.php?id=54549&r=notwrong
Not enough info:                     
http://bugs.php.net/fix.php?id=54549&r=notenoughinfo
Submitted twice:                     
http://bugs.php.net/fix.php?id=54549&r=submittedtwice
register_globals:                    
http://bugs.php.net/fix.php?id=54549&r=globals
PHP 4 support discontinued:          http://bugs.php.net/fix.php?id=54549&r=php4
Daylight Savings:                    http://bugs.php.net/fix.php?id=54549&r=dst
IIS Stability:                       
http://bugs.php.net/fix.php?id=54549&r=isapi
Install GNU Sed:                     
http://bugs.php.net/fix.php?id=54549&r=gnused
Floating point limitations:          
http://bugs.php.net/fix.php?id=54549&r=float
No Zend Extensions:                  
http://bugs.php.net/fix.php?id=54549&r=nozend
MySQL Configuration Error:           
http://bugs.php.net/fix.php?id=54549&r=mysqlcfg

Reply via email to