1#include <stdio.h> 2#include <stdlib.h> 3#include <string.h> 4int main () 5{ 6struct base { 7 int basic; 8}; 9 10struct derived { 11 struct base common; 12 char extra; 13}; 14 15struct base *bp; 16 17bp = (struct base *) malloc (sizeof (struct derived)); 18 19bp->basic = 10; 20((struct derived *)bp)->extra = 'x'; 21return 0; 22} 23