clang -O2  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations time/timespec_get.c -o time/timespec_get -D_POSIX_C_SOURCE=202405L  -lm  -lintl
time/timespec_get.c:5:38: error: use of undeclared identifier 'timespec_get'
int (*foo)(struct timespec *, int) = timespec_get;
                                     ^
1 error generated.