1 #include <stdio.h> 2 #include <stdlib.h> 3 #include <string.h> 4 int main () 5 { 6 struct base { 7 int basic; 8 }; 9 10 struct derived { 11 struct base common; 12 char extra; 13 }; 14 15 struct derived d; 16 struct base *bp; 17 18 bp = (struct base *)&d; 19 20 bp->basic = 10; 21 ((struct derived *)bp)->extra = 'x'; 22 return 0; 23 } 24