>nginx должен быть сконфигурирован с опцией --with-debug

#nginx -V
nginx version: nginx/1.2.0
configure arguments: --prefix=/usr/local/etc/nginx --with-cc-opt='-I /usr/local/include' --with-ld-opt='-L /usr/local/lib' --conf-path=/usr/local/etc/nginx/nginx.conf --sbin-path=/usr/local/sbin/nginx --pid-path=/var/run/nginx.pid --error-log-path=/var/log/nginx-error.log --user=www --group=www --with-debug --with-google_perftools_module --http-client-body-temp-path=/var/tmp/nginx/client_body_temp --http-fastcgi-temp-path=/var/tmp/nginx/fastcgi_temp --http-proxy-temp-path=/var/tmp/nginx/proxy_temp --http-scgi-temp-path=/var/tmp/nginx/scgi_temp --http-uwsgi-temp-path=/var/tmp/nginx/uwsgi_temp --http-log-path=/var/log/nginx-access.log --with-http_stub_status_module --with-pcre


#gdb /usr/local/sbin/nginx /root/nginx.core
GNU gdb 6.1.1 [FreeBSD]
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welcome to change it and/or distribute copies of it under certain conditions.
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This GDB was configured as "amd64-marcel-freebsd"...

warning: exec file is newer than core file.
Core was generated by `nginx'.
Program terminated with signal 11, Segmentation fault.
#0 0x00000000004065c3 in ngx_palloc (pool=Cannot access memory at address 0x1ae3f5
) at src/core/ngx_palloc.c:132
132 src/core/ngx_palloc.c: No such file or directory.
in src/core/ngx_palloc.c