For you

What is the output of this program and why?

#include <stdio.h>

void f(void) {
  printf("hax my anus\n");
  fflush(stdout);
  f();
}

int main(void) {
  f();
  return 0;
}

It runs forever, a valid optimization is

void f(void) {
  while (1) {
    printf("hax my anus\n");
    fflush(stdout);
  }
}

Which is why it won't crash on your machines when you compile it with GCC and use optimization (GCC does TCO).