#36828 [NEW]: segfault in special __destruct circumstances

From: locke at pushby dot com Operating system: Multiple: FreeBSD,Linux,Windows PHP version: 5.1.2 PHP Bug Type: Reproducible crash Bug description: segfault in special __destruct circumstances Description: ------------ Segfault occurs in object destructor when a number of conditions appear together. See code comment for details. This might be related to bug #36006 (http://bugs.php.net/bug.php?id=36006), but it isn't clear since commenting out *either* of the two lines indicated in the code below avoids the segfault. Reproduce code: --------------- <?php class segfault { protected $message = null; protected $foo = null; public function __construct ($message) { $this->foo = new foo ($this); $this->message = $message; } public function __destruct () { // If *either* of the following two lines are omitted, we don't segfault ... unset($this->foo); print( "MESSAGE: $this->message \n" ); } } class foo { protected $ob_ref = null; public function __construct ($ob_ref) { $this->ob_ref = $ob_ref; } } $segf = new segfault("ACK"); unset($segf); ?> Expected result: ---------------- Code prints: "MESSAGE: ACK" Actual result: -------------- No message is printed. PHP terminates with Segmentation Fault (or Bus error depending on the hardware). -- Edit bug report at http://bugs.php.net/?id=36828&edit=1 -- Try a CVS snapshot (PHP 4.4): http://bugs.php.net/fix.php?id=36828&r=trysnapshot44 Try a CVS snapshot (PHP 5.1): http://bugs.php.net/fix.php?id=36828&r=trysnapshot51 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=36828&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=36828&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=36828&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=36828&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=36828&r=needscript Try newer version: http://bugs.php.net/fix.php?id=36828&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=36828&r=support Expected behavior: http://bugs.php.net/fix.php?id=36828&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=36828&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=36828&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=36828&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=36828&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=36828&r=dst IIS Stability: http://bugs.php.net/fix.php?id=36828&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=36828&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=36828&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=36828&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=36828&r=mysqlcfg