1  struct foo
       2  {
       3    union
       4    {
       5      struct
       6      {
       7        int bar;
       8      };
       9    };
      10    union
      11    {
      12      struct
      13      {
      14        int baz;
      15        struct foo *foo;
      16      };
      17    };
      18  };
      19  
      20  struct foo *bar;