#27895 [NEW]: Access violation while throwing exception

From: mes at zeroc dot com Operating system: Windows 2000/XP PHP version: 5.0.0RC1 PHP Bug Type: Zend Engine 2 problem Bug description: Access violation while throwing exception Description: ------------ I'm using PHP 5.0.0RC1 and Apache 2.0.49 on Windows 2000 & XP. After executing the enclosed script a number of times, I eventually receive an Access Violation notice. Sometimes it happens after two executions, sometimes after 20, but it always happens. I initially used the binary distributions of PHP5 and Apache, but I've also compiled Apache and PHP5 from sources using VC 6.0 and VC 7.0, with the same result. Unfortunately, the problem only appears when I compile in release mode, not in debug mode. However, I believe the problem occurs in the first while loop of zend_fetch_debug_backtrace, where the args variable eventually points to an invalid location and is then dereferenced. Reproduce code: --------------- <HTML> <HEAD> <TITLE>Access Violation Demo</TITLE> </HEAD> <BODY> <H1>Access Violation Demo</H1> <?php if(isset($_POST["submitted"])) { echo "<HR>\n"; echo "<P>Status:<BR><B>\n"; try { throw new Exception; } catch(Exception $ex) { echo "<pre>\n"; print_r($ex); echo "</pre>\n"; } echo "</B></P>\n"; echo "<HR>\n"; } ?> <P> <FORM method="POST" action="<?php echo basename($_SERVER["PHP_SELF"]); ?>"> <INPUT type="hidden" name="submitted" value="yes"> <INPUT type="submit" name="Submit" value="Submit"> </FORM> </BODY> </HTML> Expected result: ---------------- Access violation dialog Actual result: -------------- Can't get a useful stack trace because it doesn't seem to happen in debug mode. -- Edit bug report at http://bugs.php.net/?id=27895&edit=1 -- Try a CVS snapshot (php4): http://bugs.php.net/fix.php?id=27895&r=trysnapshot4 Try a CVS snapshot (php5): http://bugs.php.net/fix.php?id=27895&r=trysnapshot5 Fixed in CVS: http://bugs.php.net/fix.php?id=27895&r=fixedcvs Fixed in release: http://bugs.php.net/fix.php?id=27895&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=27895&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=27895&r=needscript Try newer version: http://bugs.php.net/fix.php?id=27895&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=27895&r=support Expected behavior: http://bugs.php.net/fix.php?id=27895&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=27895&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=27895&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=27895&r=globals PHP 3 support discontinued: http://bugs.php.net/fix.php?id=27895&r=php3 Daylight Savings: http://bugs.php.net/fix.php?id=27895&r=dst IIS Stability: http://bugs.php.net/fix.php?id=27895&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=27895&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=27895&r=float