Function pointer

test/core/test_ccall.cpp:27–31

  return (x + y) * z;
}
int *pointer(int *in) {
  printf("%d\n", *in);
  static int ret = 21;
  return &ret;
}

// This test checks that ccall restores the stack correctly to whatever it was
// when ccall was entered.  We save the stack pointer on the heap in stackChecker