cc -O2 -pipe  -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations fcntl/posix_fallocate.c -o fcntl/posix_fallocate -D_POSIX_C_SOURCE=202405L  -lm -lpthread 
fcntl/posix_fallocate.c:6:33: error: use of undeclared identifier 'posix_fallocate'
int (*foo)(int, off_t, off_t) = posix_fallocate;
                                ^
1 error generated.