php.net |  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login

go to bug id or search bugs for

Bug #61736 warning in usort when calling debug_backtrace
Submitted: 2012-04-15 12:27 UTC Modified: 2013-01-31 14:42 UTC
Votes:7
Avg. Score:3.7 ± 1.4
Reproduced:6 of 6 (100.0%)
Same Version:2 (33.3%)
Same OS:4 (66.7%)
From: hosiplan at gmail dot com Assigned:
Status: Not a bug Package: Arrays related
PHP Version: 5.4.1 OS: Linux
Private report: No CVE-ID: None
View Developer Edit
Welcome back! If you're the original bug submitter, here's where you can edit the bug or add additional notes.
If you forgot your password, you can retrieve your password here.
Password:
Status:
Package:
Bug Type:
Summary:
From: hosiplan at gmail dot com
New email:
PHP Version: OS:

 

 [2012-04-15 12:27 UTC] hosiplan at gmail dot com 
Description:
------------
When I call a function debug_backtrace() in usort() callback, it triggers 
unrelated warning. 

When i var_dump() it's result, it's OK.


Verified on my mashine
$ php -v
PHP 5.3.11-dev (cli) (built: Mar  1 2012 16:31:39) 

and on my friend's mashine with 5.3.5

Test script:
---------------
<?php

error_reporting(E_ALL | E_STRICT);

$versions = array('1', '2');

usort($versions, function ($me, $him) {
	debug_backtrace(FALSE);
	return 1;
});


Expected result:
----------------
No warning

Actual result:
--------------
Warning: usort() [function.usort]: Array was modified by the user comparison 
function in /home/hosiplan/develop/testing/php/backtrace.error.php on line 18

Patches

Pull Requests

History

AllCommentsChangesGit/SVN commitsRelated reports
 [2012-04-16 08:17 UTC] hosiplan at gmail dot com 
Affects version
 [2012-04-16 08:17 UTC] hosiplan at gmail dot com
-PHP Version: 5.3.10 +PHP Version: 5.4.1
 [2012-04-26 13:44 UTC] arjen at react dot com 
This worked in 5.3.0, it's broken in 5.3.1-5.3.11 and 5.4.0-5.4.1.

http://3v4l.org/1UiAq
 [2013-01-31 14:17 UTC] christopher dot loerken at bytro dot com 
This problem still exists in currentl stable 5.4.11
 [2013-01-31 14:42 UTC] johannes@php.net
-Status: Open +Status: Not a bug
 [2013-01-31 14:42 UTC] johannes@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

User debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS); else the array is provided as a part of the retuned array. The engine then can'T guarantee there won't be any changes ... and changes during a sort can lead to unpredictable results.
 
PHP Copyright © 2001-2025 The PHP Group
All rights reserved. 		Last updated: Tue Nov 04 21:00:01 2025 UTC