cc -O2 -pipe  -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations errno/EMULTIHOP.c -o errno/EMULTIHOP -D_POSIX_C_SOURCE=202405L  -lm -lpthread 
errno/EMULTIHOP.c:3:2: error: "EMULTIHOP is not defined"
#error "EMULTIHOP is not defined"
 ^
1 error generated.