gistfile1.txt

typedef struct Foo Foo;

Foo *bar;   // this is ok

void bartest()
{
   bar->a = 2; // this is NOT ok, struct Foo is not defined
}

// Note, no typedef here, just defining struct Foo
struct Foo {
  int a, b;
};

var bartest2()
{
   bar->a = 2;  // this is ok, Foo is now defined
}