GNU gdb 6.1.1 [FreeBSD]
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This GDB was configured as "amd64-marcel-freebsd"...(no debugging symbols found)...
Attaching to program: /usr/local/bin/php, process 71888
Reading symbols from /lib/libcrypt.so.5...(no debugging symbols found)...done.
Loaded symbols for /lib/libcrypt.so.5
Reading symbols from /usr/local/lib/libpcre.so.1...(no debugging symbols found)...done.
Loaded symbols for /usr/local/lib/libpcre.so.1
Reading symbols from /lib/libm.so.5...(no debugging symbols found)...done.
Loaded symbols for /lib/libm.so.5
Reading symbols from /usr/local/lib/libxml2.so.5...(no debugging symbols found)...done.
Loaded symbols for /usr/local/lib/libxml2.so.5
Reading symbols from /lib/libz.so.5...(no debugging symbols found)...done.
Loaded symbols for /lib/libz.so.5
Reading symbols from /usr/local/lib/libiconv.so.3...(no debugging symbols found)...done.
Loaded symbols for /usr/local/lib/libiconv.so.3
Reading symbols from /lib/libthr.so.3...(no debugging symbols found)...done.
[New Thread 8017021c0 (LWP 100379)]
Loaded symbols for /lib/libthr.so.3
Reading symbols from /lib/libc.so.7...(no debugging symbols found)...done.
Loaded symbols for /lib/libc.so.7

 ... here is loading all PHP extension symbols (removed)

[Switching to Thread 8017021c0 (LWP 100379)]
0x0000000801529b1c in poll () from /lib/libc.so.7
(gdb) bt  
#0  0x0000000801529b1c in poll () from /lib/libc.so.7
#1  0x000000080137e7fe in poll () from /lib/libthr.so.3
#2  0x000000080abad6f9 in gearman_wait (universal=@0x81b2e2c60) at libgearman/universal.cc:270
#3  0x000000080abb04ee in gearman_worker_wait (worker=0x801746230) at libgearman/worker.cc:478
#4  0x000000080aa87918 in zif_gearman_worker_wait (ht=Variable "ht" is not available.
) at /usr/home/fruit/web/php-src/ext/php-ext-gearman/php_gearman.c:3379
#5  0x0000000801b061ee in xdebug_execute_internal () from /usr/local/lib/php/20090626/xdebug.so
#6  0x00000000005bf15d in zend_do_fcall_common_helper_SPEC ()
#7  0x00000000005be890 in execute ()
#8  0x0000000801b05e5d in xdebug_execute () from /usr/local/lib/php/20090626/xdebug.so
#9  0x0000000000594a8e in zend_execute_scripts ()
#10 0x000000000053f447 in php_execute_script ()
#11 0x0000000000621ef2 in main ()
#12 0x000000000041a4be in _start ()
#13 0x0000000800978000 in ?? ()
#14 0x0000000000000000 in ?? ()
#15 0x0000000000000000 in ?? ()
#16 0x0000000000000002 in ?? ()
#17 0x00007fffffffec50 in ?? ()
#18 0x00007fffffffec54 in ?? ()
#19 0x0000000000000000 in ?? ()

 ... and similar 700 lines (removed)
 
#726 0x00007fffffffe9b8 in ?? ()
#727 0x0000000000000002 in ?? ()
#728 0x00007fffffffe9d0 in ?? ()
#729 0x000000000000001c in ?? ()
Error accessing memory address 0x800000000000: Bad address.