Bogus VC++ 2012 error?

gistfile1.cpp

// This is yielding warning C4100: 'data' : unreferenced formal parameter in VC++ 2012.
// which seems bogus. Thoughts?

template <typename T, typename P, typename P2>
HANDLE CreateThread(SECURITY_ATTRIBUTES* sa, SIZE_T stackSize, T* obj, DWORD(T::* func)(P), P2 data, const char* name, DWORD flags, DWORD* tid)
{
	typedef DWORD(T::* F)(P);
	std::unique_ptr<utility::ThreadInfoMemberFn<T, P, F> > ti(new utility::ThreadInfoMemberFn<T, P, F>(obj, func, data, name));
	HANDLE rv(::CreateThread(sa, stackSize, utility::ThreadDispatchMemberFn<T, P, F>, static_cast<void*>(ti.get()), flags, tid));
	if(NULL != rv) { ti.release(); }
	return rv;
}