Consider this C header:

```
struct Outer {
    struct Inner { int x; } a;
};

typedef struct Inner T;
```

The generated code for T is like this:

```
public class T extends Outer.Inner { ... }
```

This is all good, but Outer.Inner is final:

```
public class Outer {
    ...
    public static class Inner { ... }
}
```

So this program will fail to compile.