Documentation
#include <stdlib.h>

void g(int *p) {
  if (p != 0) {
    p[0] = 10;
  }
}

void h(int *p) { p[1] = 20; }

void f(int size) {
  int *p = (int *)malloc(size * sizeof(int));
  g(p);
  h(p);
}

int main() {
  int i = 0;
  int j = 10;
  f(i + j);
}