#29044 [Opn->Asn]: compact function doesn't take account of infinitly recursive arrays

ID: 29044 Updated by: jani@php.net Reported By: tomas_matousek at hotmail dot com -Status: Open +Status: Assigned Bug Type: Reproducible crash Operating System: * PHP Version: 5.2.5 -Assigned To: +Assigned To: nicholsr New Comment: AFAICT, this was fixed today? Previous Comments: ------------------------------------------------------------------------ [2008-01-24 12:08:10] nicholsr@php.net Reopening this bug because I reproduced it today on 5.2.5 and on HEAD and was about to raise my own bug for this. The problem is still clearly present from code inspection. Since this bug was originally raised the technique proposed by Tomas has been used successfully in several other recursive array functions such as for example array_walk_recursive and array_merge_recursive. I think compact could be fixed in the same way. I have a more extensive test case than the one Tomas supplied which I will commit to head but not to the 5.3 and 5.2 branches (to avoid adding breaking tests to stable branches.) The test case will be called compact_variation1.phpt ------------------------------------------------------------------------ [2005-03-16 01:00:06] php-bugs at lists dot php dot net No feedback was provided for this bug for over a week, so it is being suspended automatically. If you are able to provide the information that was originally requested, please do so and change the status of the bug back to "Open". ------------------------------------------------------------------------ [2005-03-06 20:36:46] sniper@php.net Please try using this CVS snapshot: http://snaps.php.net/php5-latest.tar.gz For Windows: http://snaps.php.net/win32/php5-win32-latest.zip ------------------------------------------------------------------------ [2004-07-07 11:13:40] tomas_matousek at hotmail dot com I don't think it very hard. You can add a flag to each array, e.g. bool visited, which will be false on array creation. You set the flag to true when going down the recursion and clears it on return. Than it suffice to test whether the flag has been set. Functions such print_r does detect recursion in some way. ------------------------------------------------------------------------ [2004-07-07 11:05:41] helly@php.net Nothing much we could do about it. Detecting a recursion at the same level, as in your example, is easy but detecting multi-level recursion is very hard. Also it would slow down the function very much and require lots of memory when it is used with multi level arrays. Maybe we can disallow array references or something like that. Patch is here: http://marcus-boerger.de/php/ext/bug29044.diff.txt please try. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at http://bugs.php.net/29044 -- Edit this bug report at http://bugs.php.net/?id=29044&edit=1