Hi all!

I have a problem with a friend declaration

When compiling with gcc 2.95.2 I get an Internal compiler error.
When compiling with a recent snapshot I get an error message.
After reading the standard I don't understand what is legal C++.
Can someone explain?

I am trying to use typedefs in a friend declaration.
I suspect that this illegal since this is not an
"elaborated-type-specifier".
But I do not really know what that means ....

I will give 2 code examples together with compiler error messages.
If someone knows what really is correct or not I would be greatful!
If none of the code I have written is correct, is there a short answer to
"How much typedef you can use in a friend declaration" ?

---------------------
Example 1:
This code gives 2 different result with 2 different compiler versions.
With gcc 2.95.2:
bug2.cpp:20: Internal compiler error.
bug2.cpp:20: Please submit a full bug report.
With the mainline compiler (2.96 20000125 (experimental)):
bug2.cpp:20: typedef `Singleton<S, NoCleanupMgr2>::InstantiatorType' in
elaborated type specifier
bug2.cpp:20: ANSI C++ forbids declaration of `type name' with no type
----------
template <typename SINGLETON, typename MANAGER> class SingletonTraits { };

template <typename SINGLETON, typename MANAGER>
class Singleton

public:
  typedef typename
    SingletonTraits<SINGLETON, MANAGER>::InstantiatorType InstantiatorType;
};

class NoCleanupMgr2 {};

// Traits class
//
template <typename SINGLETON>
struct SingletonTraits<SINGLETON, NoCleanupMgr2>  {
  typedef NoCleanupMgr2 InstantiatorType;
};

class S: public Singleton<S, NoCleanupMgr2> {
  friend class Singleton<S, NoCleanupMgr2>::InstantiatorType; // Line 20
};

int main(){
  return 0;
}

---------------------------------------
Example 2:
This code compiles ok with both gcc 2.95.2 and the recent snapshot, but is
it correct?
-----
template <typename SINGLETON, typename MANAGER> class SingletonTraits { };

template <typename SINGLETON, typename MANAGER>
class Singleton

public:
  typedef typename
    SingletonTraits<SINGLETON, MANAGER>::InstantiatorType InstantiatorType;
};

class NoCleanupMgr2

public:
  class H {};
};

// Traits class
//
template <typename SINGLETON>
struct SingletonTraits<SINGLETON, NoCleanupMgr2>  {
  typedef NoCleanupMgr2::H InstantiatorType;
};


class S: public Singleton<S, NoCleanupMgr2> {
  friend class Singleton<S, NoCleanupMgr2>::InstantiatorType;
};

int main(){
  S s;
  return 0;
}
------------------------------
I would also be grateful for any constructive comments of what to do
instead,
if the code I have written is totally wrong. I am using typedefs because I
don't
whant to change the friend decl if I change the MANAGER template parameter.
So, in a complete example the class NoCleanupMgr2 would be a typedeffed in
the
class S definition. Then it would look like this:

typedef NoCleanupMgr2 Mgr;

class S: public Singleton<S, Mgr> {
  friend class Singleton<S, Mgr>::InstantiatorType;
};
---
Best regards, Peter Nordlund



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