Thank you for this bug report. To properly diagnose the problem, we
need a backtrace to see what is happening behind the scenes. To
find out how to generate a backtrace, please read
http://bugs.php.net/bugs-generating-backtrace.php for *NIX and
http://bugs.php.net/bugs-generating-backtrace-win32.php for Win32

Once you have generated a backtrace, please submit it to this bug
report and change the status back to "Open". Thank you for helping
us make PHP better.

we really need a testscript or backtrace to diagnosis the problem

As I said I was not able to get a stacktrace on windows, so I decided to try it on ubuntu. After building the same php version I used on windows, I was able to get php to crash with my application. 
However, I was not able to get a stacktrace in this case either. It just says "No stack." at the end. I did get some other messages but I doubt it will be of any help.

I want to help as much as I can on this, but I'm not familiar with core dumps and stacktraces. If I could get some help generating these I would appreciate it.

jgroth@ubuntu:~$ gdb php
GNU gdb (GDB) 7.5-ubuntu
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
Reading symbols from /usr/local/bin/php...done.
(gdb) run /home/jgroth/crash-test/sorona-tms/src/main/php/index.php test
Starting program: /usr/local/bin/php /home/jgroth/crash-test/sorona-tms/src/main/php/index.php test
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Fri Oct 19 02:21:01 2012]  Script:  '/home/jgroth/crash-test/sorona-tms/src/main/php/index.php'
---------------------------------------
/tmp/php-5.4.8/Zend/zend_opcode.c(404) : Block 0x016854a8 status:
Invalid pointer: ((prev=0x00000248) != (prev.size=0x00000510))
---------------------------------------
[Fri Oct 19 02:21:01 2012]  Script:  '/home/jgroth/crash-test/sorona-tms/src/main/php/index.php'
---------------------------------------
/tmp/php-5.4.8/Zend/zend_opcode.c(404) : Block 0x01682188 status:
Invalid pointer: ((size=0x00000108) != (next.prev=0x000001b0))
Invalid pointer: ((prev=0x000000a9) != (prev.size=0x000001b0))
---------------------------------------
[Fri Oct 19 02:21:01 2012]  Script:  '/home/jgroth/crash-test/sorona-tms/src/main/php/index.php'
---------------------------------------
/tmp/php-5.4.8/Zend/zend_opcode.c(404) : Block 0x016857d0 status:
Beginning:      Freed
    Start:      OK
      End:      OK
---------------------------------------
[Inferior 1 (process 6653) exited normally]
(gdb) bt
No stack.
(gdb)

Ok, so I have somewhat been able to reproduce the problem. I can still not do it in a small script, but I have been able to remove enough code from my application so I can send it to anyone who might be looking into this issue. The application is based on CodeIgniter, so it's basicly the CI code + a few extra files from my application.

great, if it's okey, you can tar your application as a reproduce script for us

I could not find a way to upload anything to this report so I created a temporary repository over at github with the source. I hope this is OK, you can find it here: https://github.com/jgroth/php-crash

Something I found interesting while removing as much code as possible from my application was that I could not remove comments for some methods in some of the classes/interfaces. Doing so would not reproduce the bug. Also, when I turned off error reporting, I did not get the bug either.

Note that there is one "Notice" error reported by PHP in this test application. I do not have any such errors in the full application, but still got a php crash.

thanks, I can reproduce now, dmitry, seems related to the previous traits bug we 
fixed.

A simple reproduce script:

<?php

new Attachment("");

function __autoload($class) {
    switch ($class) {
    case "Attachment":
        eval(<<<'PHP'
class Attachment extends File {
}
PHP
    );
        break;
    case "File":
        eval(<<<'PHP'
class File {
    use TDatabaseObject {
        TDatabaseObject::__construct as private databaseObjectConstruct;
    }
    public function __construct() {
    }
}
PHP
    );
        break;
    case "TDatabaseObject":
        eval(<<<'PHP'
trait TDatabaseObject {
    public function __construct() {
    }
}
PHP
    );
        break;
    }
    return TRUE;
}