1  #include <stdio.h>
       2  #include <string.h>
       3  #include <stdlib.h>
       4  
       5  typedef struct{void*super;int name;int size;}t;
       6  t*f(t*clas,int size)
       7  {
       8    t*child=(t*)malloc(size);
       9    memcpy(child,clas,clas->size);
      10    child->super=clas;
      11    child->name=0;
      12    child->size=size;
      13    return child;
      14  }
      15  main()
      16  {
      17    t foo,*bar;
      18    memset(&foo,37,sizeof(t));
      19    foo.size=sizeof(t);
      20    bar=f(&foo,sizeof(t));
      21    if(bar->super!=&foo||bar->name!=0||bar->size!=sizeof(t))abort();
      22    exit(0);
      23  }