Bug #54973 [Bgs]: SimpleXML casts intergers wrong.
Edit report at http://bugs.php.net/bug.php?id=54973&edit=1
ID: 54973
Updated by: dtajchreber@php.net
Reported by: bphelpsen at gmail dot com
Summary: SimpleXML casts intergers wrong.
Status: Bogus
Type: Bug
Package: SimpleXML related
Operating System: Linux
PHP Version: 5.3.6
Block user comment: N
Private report: N
New Comment:
This looks like a bug... SimpleXML's cast_object handler doesn't check for
overflow when trying to convert a node value to a
long. $xml->value goes through Zend's add_function and gets passed to
zendi_convert_scalar_to_number which calls SimpleXML's
cast_object handler because $xml->number is an object. It then gets chopped into
LONG_MAX by strtol. An overflow check could
fix this... but it might break some BC....
[1] http://lxr.php.net/xref/PHP_5_3/Zend/zend_operators.c#758
[2] http://lxr.php.net/xref/PHP_5_3/ext/simplexml/simplexml.c#1722
[3] http://lxr.php.net/xref/PHP_5_3/Zend/zend_operators.c#355
[4] http://lxr.php.net/xref/PHP_5_3/Zend/zend_operators.c#768
[5] http://www.gnu.org/s/hello/manual/libc/Parsing-of-Integers.html
Previous Comments:
------------------------------------------------------------------------
[2011-06-02 20:05:07] bphelpsen at gmail dot com
Then why do I get different results when I run this code:
<?php echo "214748364800" / 1024 / 1024 / 1024; ?>
than when I run the example code. Shouldn't they return the same value?
Here is an example, with the same results as my local test:
http://codepad.org/KICl3xHw
------------------------------------------------------------------------
[2011-06-02 20:00:54] iliaa@php.net
Thank you for taking the time to write to us, but this is not
a bug. Please double-check the documentation available at
http://www.php.net/manual/ and the instructions on how to
report
a bug at http://bugs.php.net/how-to-report.php
This has nothing to do with SimpleXML, but rather the fact that a numeric string
in PHP by default would converted to an integer.
------------------------------------------------------------------------
[2011-06-01 22:18:27] bphelpsen at gmail dot com
Description:
------------
When an XML node value is an integer SimpleXML always casts it to an int, even if its a float or
double.
Test script:
---------------
<?php
$xml =
simplexml_load_string("<xml><number>214748364800</number></xml>");
echo $xml->number . "\n"; // the proper number
$int = $xml->number / 1024 / 1024 / 1024; // initial cast to an int causes problems
echo $int . "\n";
$double = (double) $xml->number / 1024 / 1024 / 1024; // hard cast to a double fixes it
echo $double . "\n";
?>
Expected result:
----------------
214748364800
200
200
Actual result:
--------------
214748364800
1.9999999990687
200
------------------------------------------------------------------------
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Edit this bug report at http://bugs.php.net/bug.php?id=54973&edit=1
Thread (10 messages)