ID: 32434
User updated by: [EMAIL PROTECTED]
Reported By: [EMAIL PROTECTED]
-Status: Feedback
+Status: Open
Bug Type: Variables related
Operating System: Windows XP
PHP Version: 4.3.10
New Comment:
I'm maintaining a PHP library that generate or extract zip files in PHP
(PclZip on www.phpconcept.net).
Today this library does not support zip encryption. To support zip
encryption I need to do this kind of complex math ... The code for
encryption is quite ready, but failed because of this float truncate.
I wrote the bug report, because if it's a bug, and that it can be
solved, I will have the ability to propose this encryption feature. If
it can not be solved, then I will not try any more to do encryption
with PclZip.
Thanks for your support !
Vincent
Previous Comments:
------------------------------------------------------------------------
[2005-03-23 21:42:16] [EMAIL PROTECTED]
Why are you doing things like this?
------------------------------------------------------------------------
[2005-03-23 21:11:07] [EMAIL PROTECTED]
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)
------------------------------------------------------------------------
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Edit this bug report at http://bugs.php.net/?id=32434&edit=1
