cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations semaphore/sem_clockwait.c -o semaphore/sem_clockwait -D_POSIX_C_SOURCE=202405L  -lm -lpthread  -liconv
semaphore/sem_clockwait.c:5:29: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
    5 | int (*foo)(sem_t *restrict, clockid_t, const struct timespec *restrict) = sem_clockwait;
      |                             ^
      |                             int
semaphore/sem_clockwait.c:5:75: error: use of undeclared identifier 'sem_clockwait'; did you mean 'sem_trywait'?
    5 | int (*foo)(sem_t *restrict, clockid_t, const struct timespec *restrict) = sem_clockwait;
      |                                                                           ^~~~~~~~~~~~~
      |                                                                           sem_trywait
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/sys/semaphore.h:58:5: note: 'sem_trywait' declared here
   58 | int sem_trywait(sem_t *);
      |     ^
semaphore/sem_clockwait.c:5:7: error: incompatible function pointer types initializing 'int (*)(sem_t *restrict, int, const struct timespec *restrict)' (aka 'int (*)(int *restrict, int, const struct timespec *restrict)') with an expression of type 'int (sem_t *)' (aka 'int (int *)') [-Wincompatible-function-pointer-types]
    5 | int (*foo)(sem_t *restrict, clockid_t, const struct timespec *restrict) = sem_clockwait;
      |       ^                                                                   ~~~~~~~~~~~~~
3 errors generated.