tr1::function, tr1::bind and class member functions

Hello all again.

I've come across a rather annoying problem and I know it's because I'm misunderstanding something. I just can't find anything relevant anywhere on Google and the documentation for these two tr1:: objects is severely lacking.

Anyway, I use the Microsoft flavors of compilers. I've been working with a simple callback mechanism using tr1::function/tr1::bind and it's been working [mostly] well. The issue now is when it gets compiled on the mac with GCC/LLVM (although it would probably show the same problem on any other system with GCC).

The error that's popping up is this:

Code:

c++/4.2.1/tr1/functional_iterate.h:197: error: cannot apply member pointer
'((const std::tr1::_Mem_fn<void (StateManager::*)(Event&)>*)this)->std::tr1::_Mem_fn<void (StateManager::*)(Event&)>::__pmf'
to '* __ptr', which is of non-class type 'StateManager*'

The specific line of code it's referencing is this one:

Code:

eventHandler.register_callback(EVENT_TYPE_1, std::tr1::bind(&StateManager::handleEvent, &stateManager, std::tr1::placeholders::_1));

The following is the code in context (forgive me for the length):

Code:

enum EventType { EVENT_TYPE_1, EVENT_TYPE_2 };


struct Event
{
    int value1;
    int value2;
    EventType type;
};


class EventHandler
{
public:
    typedef std::tr1::function<void(Event& event)> Callback;

    EventHandler()
    {}

    void register_callback(EventType type, Callback callback)
    {
        mCallbackMap.insert(pair<EventType, Callback>(type, callback));
    }

private:
    typedef std::multimap<EventType, Callback> CallbackMap;

    CallbackMap mCallbackMap;
};


class MyClass
{
public:
    go()
    {
        EventHandler eventHandler;

        eventHandler.register_callback(EVENT_TYPE_1, std::tr1::bind(&StateManager::handleEvent, &stateManager, std::tr1::placeholders::_1));
    }

private:
    StateManager stateManager;
};

Breaking down the error, I'm reading it as "Can't assign member pointer '_pmf' to '* _ptr', a pointer to a StateManager, the pointer not being a class". Confusing, I'm sure, but what's the problem here? Is this something I'm misunderstanding or is this a bug in GCC's implementation of tr1::bind? I'm hesitent to believe that though. How can I resolve this?

I did a bit of digging around and I believe I may have found the issue.

It seems that bind() and related objects/functions have an issue when it comes to binding member functions of non-local objects (e.g., in this case StateManager is a member attribute of MyClass and is thus not a local object). I don't know if this is a flaw in the GCC code, a flaw in the specification, an artifact of ambiguity or actually intended.

By removing StateManager as a member attribute and instead making it a local object, the problem disappears.

I guess my question now, then, is why is this so? I couldn't find much information about it except for some speculations on a few sites.