Maybe this info from gdb can help too:

(gdb) frame 0
#0 0x4f3408cb in xdebug_execute_internal (current_execute_data=0x84536d4, return_value_used=0)
at /var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug.c:1321
1321 in /var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug.c
(gdb) print current_execute_data
$1 = (zend_execute_data ) 0x84536d4
(gdb) print return_value_used
$2 = 0
(gdb) x 0x84536d4
0x84536d4: 0x083fbe00
(gdb) x 0x083fbe00
0x83fbe00: 0x5010d530
(gdb) x 0x5010d530
0x5010d530 <ZEND_DO_FCALL_SPEC_CONST_HANDLER>: 0x57e58955
(gdb) print edata
$3 = (zend_execute_data ) 0x0
(gdb) print fse
$4 = (function_stack_entry ) 0x0
(gdb) print cur_opcode
$5 = (zend_op ) 0xffffffff
(gdb) print do_return
$6 = 0

Starting to see some memory leaks reported in apache's log too today:

[Sat Oct 23 17:56:13 2010] [notice] Apache/2.2.16 (Unix) mod_ssl/2.2.16 OpenSSL/0.9.8o configured -- resuming normal operations
[Sat Oct 23 18:04:04 2010] Script: '/home/trinitronx/sites/truthnaturals.com/wp-admin/index-extra.php'
/var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/main/SAPI.c(940) : Freeing 0x0A3D5DCC (16 bytes), script=/home/trinitronx/sites/truthnatural
s.com/wp-admin/index-extra.php
=== Total 1 memory leaks detected ===
[Sat Oct 23 18:04:02 2010] Script: '/home/trinitronx/sites/truthnaturals.com/wp-admin/index-extra.php'
/var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/main/SAPI.c(940) : Freeing 0x0A3F3204 (16 bytes), script=/home/trinitronx/sites/truthnatural
s.com/wp-admin/index-extra.php
=== Total 1 memory leaks detected ===
[Sat Oct 23 18:04:12 2010] Script: '/home/trinitronx/sites/truthnaturals.com/wp-admin/update-core.php'
/var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/main/SAPI.c(940) : Freeing 0x0A9251F8 (16 bytes), script=/home/trinitronx/sites/truthnatural
s.com/wp-admin/update-core.php
=== Total 1 memory leaks detected ===
[Sat Oct 23 18:03:49 2010] Script: '/home/trinitronx/sites/truthnaturals.com/wp-admin/index.php'
/var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/main/SAPI.c(940) : Freeing 0x0A4233EC (16 bytes), script=/home/trinitronx/sites/truthnatural
s.com/wp-admin/index.php
=== Total 1 memory leaks detected ===
[Sat Oct 23 18:04:05 2010] Script: '/home/trinitronx/sites/truthnaturals.com/wp-admin/index-extra.php'
/var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/main/SAPI.c(940) : Freeing 0x0A901774 (16 bytes), script=/home/trinitronx/sites/truthnatural
s.com/wp-admin/index-extra.php
=== Total 1 memory leaks detected ===
[Sat Oct 23 18:04:02 2010] Script: '/home/trinitronx/sites/truthnaturals.com/wp-admin/index-extra.php'
/var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/main/SAPI.c(940) : Freeing 0x0A8A4524 (16 bytes), script=/home/trinitronx/sites/truthnatural
s.com/wp-admin/index-extra.php
=== Total 1 memory leaks detected ===
[Sat Oct 23 18:57:33 2010] [notice] child pid 29651 exit signal Segmentation fault (11)
[Sat Oct 23 18:57:35 2010] [notice] child pid 29590 exit signal Segmentation fault (11)
[Sat Oct 23 18:58:34 2010] [notice] child pid 29585 exit signal Segmentation fault (11)
[Sat Oct 23 18:59:44 2010] [notice] child pid 28269 exit signal Segmentation fault (11)
[Sat Oct 23 18:59:45 2010] [notice] child pid 30170 exit signal Segmentation fault (11)

Tried having xdebug create trace file in tmp during a debug session today, and the only thing it recorded before segfaulting was this:

TRACE START [2010-10-24 01:10:35]
0.0720 385200 -> {main}() /home/trinitronx/sites/truthnaturals.com/index.php:0

Did another gdb backtrace too, and it looks a bit different:

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x4f383700 (LWP 30951)]
0x4eb9b500 in _zval_dtor_func (zvalue=0x59b9d064,
__zend_filename=0x4de2c06c "/var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug_handler_dbgp.c", __zend_lineno=1225)
at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_variables.c:35
35 /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_variables.c: No such file or directory.
in /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_variables.c

(gdb) bt
#0 0x4eb9b500 in _zval_dtor_func (zvalue=0x59b9d064,
zend_filename=0x4de2c06c "/var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug_handler_dbgp.c", zend_lineno=1225)
at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_variables.c:35
#1 0x4de146dc in _zval_dtor (zvalue=0x59b9d064,
zend_filename=0x4de2c06c "/var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug_handler_dbgp.c", zend_lineno=1225)
at /usr/lib/php5/include/php/Zend/zend_variables.h:35
0000002 0x4de1469c in xdebug_dbgp_handle_eval (retval=0x59b9d17c, context=0x4de32d54, args=0x848e5f8)
at /var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug_handler_dbgp.c:1225
0000003 0x4de1aadc in xdebug_dbgp_parse_option (context=0x4de32d54, line=0x848e498 "eval -i 5591 -- JHRoaXMtPnJhdGVbJ3NlcnZpY2VzJ10=", flags=0,
retval=0x848dd80) at /var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug_handler_dbgp.c:2260
0000004 0x4de1ae84 in xdebug_dbgp_cmdloop (context=0x4de32d54, bail=1) at /var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug_handler_dbgp.c:2309
0000005 0x4de1c60a in xdebug_dbgp_breakpoint (context=0x4de32d54, stack=0x8443d48, file=0x83f9db8 "/home/trinitronx/sites/truthnaturals.com/index.php",
lineno=14, type=2, exception=0x0, message=0x0) at /var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug_handler_dbgp.c:2606
0000006 0x4de0caf5 in xdebug_statement_call (op_array=0x83f9bb0) at /var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug.c:1748
0000007 0x4ebd05dd in zend_extension_statement_handler (extension=0x82fcfc0, op_array=0x83f9bb0)
at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_execute.c:740
0000008 0x4eb919b1 in zend_llist_apply_with_argument (l=0x4f10d0cc, func=0x4ebd05bf <zend_extension_statement_handler>, arg=0x83f9bb0)
at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_llist.c:428
0000009 0x4ebd4941 in ZEND_EXT_STMT_SPEC_HANDLER (execute_data=0x844d8cc)
at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_vm_execute.h:530
0000010 0x4ebd5468 in ZEND_USER_OPCODE_SPEC_HANDLER (execute_data=0x844d8cc)
at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_vm_execute.h:706
0000011 0x4ebd219d in execute (op_array=0x83f9bb0) at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend_vm_execute.h:107
0000012 0x4de0b64a in xdebug_execute (op_array=0x83f9bb0) at /var/tmp/portage/dev-php5/xdebug-2.1.0/work/xdebug-2.1.0/xdebug.c:1272
0000013 0x4ddeeebd in suhosin_execute_ex (op_array=0x83f9bb0, zo=0, dummy=0) at /var/tmp/portage/dev-php5/suhosin-0.9.31/work/suhosin-0.9.31/execute.c:583
0000014 0x4ddeef07 in suhosin_execute (op_array=0x83f9bb0) at /var/tmp/portage/dev-php5/suhosin-0.9.31/work/suhosin-0.9.31/execute.c:595
0000015 0x4eb9e3d3 in zend_execute_scripts (type=8, retval=0x0, file_count=3)
at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/Zend/zend.c:1266
0000016 0x4eb25d2d in php_execute_script (primary_file=0x59b9f820) at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/main/main.c:2275
0000017 0x4ec74913 in php_handler (r=0x8431330) at /var/tmp/portage/dev-lang/php-5.3.3-r1/work/sapis-build/apache2/sapi/apache2handler/sapi_apache2.c:673
0000018 0x08075c34 in ap_run_handler (r=0x8431330) at config.c:158
0000019 0x08078be5 in ap_invoke_handler (r=0x8431330) at config.c:376
0000020 0x080832b2 in ap_internal_redirect (new_uri=0x8431320 "/index.php", r=0x842ad38) at http_request.c:502
0000021 0x4f2d60a4 in handler_redirect (r=0x842ad38) at mod_rewrite.c:4856
0000022 0x08075c34 in ap_run_handler (r=0x842ad38) at config.c:158
0000023 0x08078be5 in ap_invoke_handler (r=0x842ad38) at config.c:376
0000024 0x0808342e in ap_process_request (r=0x842ad38) at http_request.c:282
0000025 0x0808081c in ap_process_http_connection (c=0x841e6e8) at http_core.c:190
0000026 0x0807c8c0 in ap_run_process_connection (c=0x841e6e8) at connection.c:43
0000027 0x08087f26 in child_main (child_num_arg=<value optimized out>) at prefork.c:662
0000028 0x080881c1 in make_child (s=0x80ac4e8, slot=0) at prefork.c:702
0000029 0x0808889d in ap_mpm_run (_pconf=0x80aa5f0, plog=0x80d86a8, s=0x80ac4e8) at prefork.c:978
0000030 0x08063c12 in main (argc=Cannot access memory at address 0x0
) at main.c:740

Recently I upgraded to php version 5.3.6-pl0-gentoo, and xdebug version 2.1.2dev. I also recompiled without -O2 (see http://bugs.xdebug.org/view.php?id=154).

I still am getting segfaults during a debug session. The session will start ok, however after hitting 'continue' in Eclipse, apache segfaults.

I've improved handling things with eval in Xdebug 2.1.3 and later. Can you please try?

Hello, can you please try Xdebug 2.2.0RC2?

I ran first with PHP 5.3.8 and now running with PHP 5.4.2, as I get segmentation aults. With 5.3.8 it happend occasionally, now with 5.4.2 it happens instantly:

With xdebug 2.2.0RC2, PHP 5.2.4 it crashes instantly, without executing a single line of code - everytime:

http://pastebin.com/sSri8b6k

memoryleak, can you reproduce this with a commandline script as well? If so, could you make a real backtrace as is described at https://bugs.php.net/bugs-generating-backtrace.php ?

Hi Derick, I've set up nginx + PHP-FPM, and works now without problems. Just with Apache it doesn't.

memoryleak, which MPM are you using with Apache? prefork, worker, something else?

Hi Derick,

Server-pool management (MPM prefork specific)

523 StartServers 1
524 MinSpareServers 1
525 MaxSpareServers 1
526 # ServerLimit and MaxClients support n% syntax which sets them to a
527 # fraction of the current RLIMIT_NPROC limit.
528 ServerLimit 50%
529 MaxClients 50%
530 ListenBackLog 512
531 MaxRequestsPerChild 100000

Further information: That's the Apache configuration that is comes with OS X Lion by default.

Is this still a problem for you?

@derick: The old gentoo system that I had installed this on is currently out of commission, and since I have no easy way of reproducing the bug... Not anymore ;-)

Okay, thanks. Closing this out then.