I'm not sure if this is the place to submit problems related to Zend Optimizer, but i couldnt find anything on zend.com.

I'm having reproducible crashes of Apache threads on certain pages of our CMS. Our developers are currently trying to pinpoint the critical point in the scripts to create a script for reproduction of the problem. For now the critical point seems to be around some preg_replace's.

What i do have atm is a backtrace and some sysinfo. Since Zend Optimizer doesnt load when PHP is compiled with debug info, i couldnt squeeze out any more info than this:

Program received signal SIGSEGV, Segmentation fault.
0x40582378 in zend_assign_to_variable_reference ()
   from /usr/local/Zend/ZendOptimizer.so
(gdb) bt
#0  0x40582378 in zend_assign_to_variable_reference ()
   from /usr/local/Zend/ZendOptimizer.so
#1  0x40587e8e in zend_assign_to_variable_reference ()
   from /usr/local/Zend/ZendOptimizer.so
#2  0x40587e8e in zend_assign_to_variable_reference ()
   from /usr/local/Zend/ZendOptimizer.so
#3  0x4058b325 in zend_oe () from /usr/local/Zend/ZendOptimizer.so
#4  0x8163e9a in zend_execute_scripts () at eval.c:88
#5  0x80c223d in php_execute_script () at eval.c:88
#6  0x816c0ca in apache_php_module_main () at eval.c:88
#7  0x80bf5a6 in php_restore_umask () at eval.c:88
#8  0x80bf602 in php_restore_umask () at eval.c:88
#9  0x8188969 in ap_invoke_handler () at eval.c:88
#10 0x819dd1f in ap_some_auth_required () at eval.c:88
#11 0x819dd86 in ap_process_request () at eval.c:88
#12 0x8194b46 in ap_child_terminate () at eval.c:88
#13 0x8194dea in ap_child_terminate () at eval.c:88
#14 0x8195178 in ap_child_terminate () at eval.c:88
#15 0x819574c in ap_child_terminate () at eval.c:88
#16 0x8195dac in main () at eval.c:88
#17 0x403572eb in __libc_start_main (main=0x81959f8 <main>, argc=2,
    ubp_av=0xbffffb24, init=0x8076e04 <_init>, fini=0x821acdc <_fini>,
    rtld_fini=0x4000c130 <_dl_fini>, stack_end=0xbffffb1c)
    at ../sysdeps/generic/libc-start.c:129

System is Slackware Linux 8.0 running kernel 2.2.20/glibc-2.2.3/gcc-2.95.3
Apache_1.3.22
php-4.1.1
ZendOptimizer-1.2.0-PHP_4.1.0-Linux_glibc21-i386

php config:

./configure  --with-apache=../apache_1.3.22 --with-mysql=/usr/local --with-pgsql=/usr/local --with-gd=../gd-1.8.4 --with-freetype-dir=/usr --with-jpeg-dir=/usr --with-png-dir=/usr/local --with-zlib --with-imap --with-openssl --with-curl --with-gettext --with-xml --enable-ftp --enable-sysvsem --enable-sysvshm --enable-track-vars --enable-memory-limit --enable-trans-sid --enable-debug=no

Optimizer config from php.ini:

zend_optimizer.optimization_level=15
zend_optimizer.enable_loader=0
zend_extension="/usr/local/Zend/ZendOptimizer.so"

If you need more info i'd be glad to help.