From:             jancha at trave dot lv
Operating system: Gentoo
PHP version:      5.2.12
PHP Bug Type:     Math related
Bug description:  modulus (mod) returns wrong value

Description:
------------
We came accorss following  case:

<?php echo 72.6 * 100 % 100;

You would expect: 60
But you get: 59

We did further analysis and got following results:
[OK] 72.0:0
[FAIL] 72.1:9 
[OK] 72.2:20 
[OK] 72.3:30
[OK] 72.4:40
[OK] 72.5:50
[FAIL] 72.6:59
[OK] 72.7:70
[OK] 72.8:80
[OK] 72.9:90

That makes us think that bug happens, if last digit is either 1 or 6.
Also, according to manual, operands of modulus are converted to integers by
stripping decimal part away - in our case that is not reason, as 72.6 * 100
= 7260 (float). And conversion to int should result with 7260.

Reproduce code:
---------------
<?php echo 72.6 * 100 % 100;

Expected result:
----------------
60

Actual result:
--------------
59

-- 
Edit bug report at http://bugs.php.net/?id=50824&edit=1
-- 
Try a snapshot (PHP 5.2):            
http://bugs.php.net/fix.php?id=50824&r=trysnapshot52
Try a snapshot (PHP 5.3):            
http://bugs.php.net/fix.php?id=50824&r=trysnapshot53
Try a snapshot (PHP 6.0):            
http://bugs.php.net/fix.php?id=50824&r=trysnapshot60
Fixed in SVN:                        
http://bugs.php.net/fix.php?id=50824&r=fixed
Fixed in SVN and need be documented: 
http://bugs.php.net/fix.php?id=50824&r=needdocs
Fixed in release:                    
http://bugs.php.net/fix.php?id=50824&r=alreadyfixed
Need backtrace:                      
http://bugs.php.net/fix.php?id=50824&r=needtrace
Need Reproduce Script:               
http://bugs.php.net/fix.php?id=50824&r=needscript
Try newer version:                   
http://bugs.php.net/fix.php?id=50824&r=oldversion
Not developer issue:                 
http://bugs.php.net/fix.php?id=50824&r=support
Expected behavior:                   
http://bugs.php.net/fix.php?id=50824&r=notwrong
Not enough info:                     
http://bugs.php.net/fix.php?id=50824&r=notenoughinfo
Submitted twice:                     
http://bugs.php.net/fix.php?id=50824&r=submittedtwice
register_globals:                    
http://bugs.php.net/fix.php?id=50824&r=globals
PHP 4 support discontinued:          http://bugs.php.net/fix.php?id=50824&r=php4
Daylight Savings:                    http://bugs.php.net/fix.php?id=50824&r=dst
IIS Stability:                       
http://bugs.php.net/fix.php?id=50824&r=isapi
Install GNU Sed:                     
http://bugs.php.net/fix.php?id=50824&r=gnused
Floating point limitations:          
http://bugs.php.net/fix.php?id=50824&r=float
No Zend Extensions:                  
http://bugs.php.net/fix.php?id=50824&r=nozend
MySQL Configuration Error:           
http://bugs.php.net/fix.php?id=50824&r=mysqlcfg

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