nginx 1.1.11 *) Feature: the "so_keepalive" parameter of the "listen" directive. Thanks to Vsevolod Stakhov. *) Feature: the "if_not_empty" parameter of the "fastcgi/scgi/uwsgi_param" directives. *) Feature: the $https variable. *) Feature: the "proxy_redirect" directive supports variables in the first parameter. *) Feature: the "proxy_redirect" directive supports regular expressions. *) Bugfix: the $sent_http_cache_control variable might contain a wrong value if the "expires" directive was used. Thanks to Yichun Zhang. *) Bugfix: the "read_ahead" directive might not work combined with "try_files" and "open_file_cache". *) Bugfix: a segmentation fault might occur in a worker process if small time was used in the "inactive" parameter of the "proxy_cache_path" directive. *) Bugfix: responses from cache might hang.

--- a/src/os/unix/ngx_freebsd_sendfile_chain.c
+++ b/src/os/unix/ngx_freebsd_sendfile_chain.c
@@ -246,9 +246,14 @@ ngx_freebsd_sendfile_chain(ngx_connectio
                 }
             }
 
-            hdtr.headers = (struct iovec *) header.elts;
+            /*
+             * sendfile() does unneeded work if sf_hdtr's count is 0,
+             * but corresponding pointer is not NULL
+             */
+
+            hdtr.headers = header.nelts ? (struct iovec *) header.elts: NULL;
             hdtr.hdr_cnt = header.nelts;
-            hdtr.trailers = (struct iovec *) trailer.elts;
+            hdtr.trailers = trailer.nelts ? (struct iovec *) trailer.elts: NULL;
             hdtr.trl_cnt = trailer.nelts;
 
             /*