From: [EMAIL PROTECTED]
Operating system: Windows XP
PHP version: 4.3.10
PHP Bug Type: Variables related
Bug description: Bad result for float multiplication
Description:
------------
When multiplying two float, the truncated result is not correct.
Reproduce code:
---------------
<?php
$v1 = (float)0x5a05df1b;
$v2 = (float)0x2d02ef8d;
echo 'v1='.sprintf("0x%X (%d)", $v1, $v1).'<br>';
echo 'v2='.sprintf("0x%X (%d)", $v2, $v2).'<br>';
(float)$v3=(float)$v1*(float)$v2;
echo 'v1*v2='.sprintf("0x%X (%d)", (float)$v3, (float)$v3).'<br>';
// Actual result is :
// v1=0x5A05DF1B (1510334235)
// v2=0x2D02EF8D (755167117)
// v1*v2=0x8DBC1700 (-1917053184)
//
// Result should be : 0xFD410808DBC16DF
// Truncated should be : 0x8DBC16DF
?>
Expected result:
----------------
Result should be : 0xFD410808DBC16DF, because variable is a float, result
should be truncated like that :
0x8DBC16DF
Actual result:
--------------
v1*v2=0x8DBC1700 (-1917053184)
--
Edit bug report at http://bugs.php.net/?id=32434&edit=1
--
Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=32434&r=trysnapshot4
Try a CVS snapshot (php5.0):
http://bugs.php.net/fix.php?id=32434&r=trysnapshot50
Try a CVS snapshot (php5.1):
http://bugs.php.net/fix.php?id=32434&r=trysnapshot51
Fixed in CVS: http://bugs.php.net/fix.php?id=32434&r=fixedcvs
Fixed in release: http://bugs.php.net/fix.php?id=32434&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=32434&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=32434&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=32434&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=32434&r=support
Expected behavior: http://bugs.php.net/fix.php?id=32434&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=32434&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=32434&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=32434&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=32434&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=32434&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=32434&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=32434&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=32434&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=32434&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=32434&r=mysqlcfg
