gcc -c -pipe -O -W -Wall -Wpointer-arith -Wno-unused-parameter -Wunused-function -Wunused-variable -Wunused-value -Werror -g -march=native -Ofast -fomit-frame-pointer -fstack-protector -D_FORTIFY_SOURCE=2 -flto -fwhole-program -fuse-linker-plugin -I src/core -I src/event -I src/event/modules -I src/os/unix -I objs -I src/http -I src/http/modules \ -o objs/src/http/ngx_http_spdy.o \ src/http/ngx_http_spdy.c

src/http/ngx_http_spdy.c: In function ‘ngx_http_init_spdy’:

src/http/ngx_http_spdy.c:261:34: error: variable ‘rc’ set but not used [-Werror=unused-but-set-variable]

src/http/ngx_http_spdy.c: In function ‘ngx_http_spdy_process_ping’:

src/http/ngx_http_spdy.c:1512:35: error: variable ‘c’ set but not used [-Werror=unused-but-set-variable]

src/http/ngx_http_spdy.c: In function ‘ngx_http_spdy_send_rst_stream’:

src/http/ngx_http_spdy.c:2552:35: error: variable ‘c’ set but not used [-Werror=unused-but-set-variable] cc1: all warnings being treated as errors

I would point out that the -Werror is set by the vanilla version of nginx and not a flag that I passed in.