From:             zerkyn at gmail dot com
Operating system: Windows 7, Linux
PHP version:      5.3.14
Package:          SimpleXML related
Bug Type:         Bug
Bug description:SimpleXML memory leak, if circular references are removed by 
Garbage Collector

Description:
------------
The SimpleXMLElement memory leaks, when:
1) An object holds reference to a SimpleXMLElement, and
2) The object is involved in a circular references net, and
3) All external references to that net are cleared, so Garbage Collector
finds that net, correctly sees it as a garbage cycle, and cleans all its
objects

After the Garbage Collector finishes its work, the memory, consumed by
SimpleXMLElement is not freed, thus producing a memory leak.

The issue is reproduced both at Windows and Linux platforms.

Full version for the test script is there:
https://dl.dropbox.com/u/17950262/php/issues/simplexml_memory_leak.zip


Test script:
---------------
<?php
class SelfLinked
{
    public $xml;
    public $me;

    public function __construct()
    {
        $this->xml =
simplexml_load_file('pretty_big_file_of_1mb_size.xml');
        $this->me = $this;
    }
}

echo "Sys memory usage before: ", SystemMemoryUsage(), "\n";

for ($i = 0; $i < 1000; $i++) {
    $a = new SelfLinked();
    unset($a);
    gc_collect_cycles();
}

echo "Sys memory usage after: ", SystemMemoryUsage(), "\n";

/** ----------------------------------------------------- */
function SystemMemoryUsage() 
{
    ... 
    // Return memory consumption by executing system tool - tasklist, ps or
anything else
    // See https://bugs.php.net/bug.php?id=62467 on proper memory profiling
of SimpleXML functions
}
}

Expected result:
----------------
Memory consumption does not change.

Actual result:
--------------
Huge increase of memory consumption is reported.

-- 
Edit bug report at https://bugs.php.net/bug.php?id=62468&edit=1
-- 
Try a snapshot (PHP 5.4):            
https://bugs.php.net/fix.php?id=62468&r=trysnapshot54
Try a snapshot (PHP 5.3):            
https://bugs.php.net/fix.php?id=62468&r=trysnapshot53
Try a snapshot (trunk):              
https://bugs.php.net/fix.php?id=62468&r=trysnapshottrunk
Fixed in SVN:                        
https://bugs.php.net/fix.php?id=62468&r=fixed
Fixed in SVN and need be documented: 
https://bugs.php.net/fix.php?id=62468&r=needdocs
Fixed in release:                    
https://bugs.php.net/fix.php?id=62468&r=alreadyfixed
Need backtrace:                      
https://bugs.php.net/fix.php?id=62468&r=needtrace
Need Reproduce Script:               
https://bugs.php.net/fix.php?id=62468&r=needscript
Try newer version:                   
https://bugs.php.net/fix.php?id=62468&r=oldversion
Not developer issue:                 
https://bugs.php.net/fix.php?id=62468&r=support
Expected behavior:                   
https://bugs.php.net/fix.php?id=62468&r=notwrong
Not enough info:                     
https://bugs.php.net/fix.php?id=62468&r=notenoughinfo
Submitted twice:                     
https://bugs.php.net/fix.php?id=62468&r=submittedtwice
register_globals:                    
https://bugs.php.net/fix.php?id=62468&r=globals
PHP 4 support discontinued:          
https://bugs.php.net/fix.php?id=62468&r=php4
Daylight Savings:                    https://bugs.php.net/fix.php?id=62468&r=dst
IIS Stability:                       
https://bugs.php.net/fix.php?id=62468&r=isapi
Install GNU Sed:                     
https://bugs.php.net/fix.php?id=62468&r=gnused
Floating point limitations:          
https://bugs.php.net/fix.php?id=62468&r=float
No Zend Extensions:                  
https://bugs.php.net/fix.php?id=62468&r=nozend
MySQL Configuration Error:           
https://bugs.php.net/fix.php?id=62468&r=mysqlcfg

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