cc -pthread  -Wall -Wextra quick_exit.c -o quick_exit -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE  -lm -lpthread  -liconv
quick_exit.c:9:2: error: implicit declaration of function 'quick_exit' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
        quick_exit(0);
        ^
1 error generated.