Nginx mod security fails to compile

I am trying to compile modsecurity 2.7.7 (this download link) along with nging 1.15.8 but I am having issues where it will not compile.

Commands used when compiling modsecurity:

./autogen.sh ./configure --enable-standalone-module 

This is the error I am getting when I compile.

objs/Makefile:1278: recipe for target 'objs/addon/modsecurity/ngx_http_modsecurity.o' failed make[1]: Leaving directory '/work-disk/server_setup/compile_nginx/nginx' Makefile:11: recipe for target 'install' failed STDERR: /work-disk/server_setup/compile_nginx/mod_security/nginx/modsecurity/ngx_http_modsecurity.c: In function ‘ngx_http_modsecurity_save_request_body’: /work-disk/server_setup/compile_nginx/mod_security/nginx/modsecurity/ngx_http_modsecurity.c:531:15: error: ‘ngx_http_connection_t {aka struct <anonymous>}’ has no member named ‘nfree’          if (hc->nfree && size == cscf->large_client_header_buffers.size) {                ^ /work-disk/server_setup/compile_nginx/mod_security/nginx/modsecurity/ngx_http_modsecurity.c:533:32: error: ‘ngx_http_connection_t {aka struct <anonymous>}’ has no member named ‘nfree’              buf = hc->free[--hc->nfree];                                 ^ make[1]: *** [objs/addon/modsecurity/ngx_http_modsecurity.o] Error 1 make: *** [build] Error 2 /work-disk/server_setup/compile_nginx/mod_security/nginx/modsecurity/ngx_http_modsecurity.c: In function ‘ngx_http_modsecurity_save_request_body’: /work-disk/server_setup/compile_nginx/mod_security/nginx/modsecurity/ngx_http_modsecurity.c:531:15: error: ‘ngx_http_connection_t {aka struct <anonymous>}’ has no member named ‘nfree’          if (hc->nfree && size == cscf->large_client_header_buffers.size) {                ^ /work-disk/server_setup/compile_nginx/mod_security/nginx/modsecurity/ngx_http_modsecurity.c:533:32: error: ‘ngx_http_connection_t {aka struct <anonymous>}’ has no member named ‘nfree’              buf = hc->free[--hc->nfree];                                 ^ make[1]: *** [objs/addon/modsecurity/ngx_http_modsecurity.o] Error 1 make: *** [install] Error 2