source: CIVL/mods/dev.civl.abc/examples/prune/structs1.c

typedef int time_t;
struct tm;
char *asctime(const struct tm *timeptr);
struct tm *gmtime(const time_t *timer);
struct tm *localtime(const time_t *timer);
struct tm { int x; };

int main() {
  asctime((struct tm *)0);
  return 0;
}