Test program:

template <class T> class foo
{
public:
    static const unsigned long long max = (T)~0ULL;
    bool toobig (unsigned long long val) 
    {
        return val > max;
    }
};

Message:

test.cc: In member function ‘bool foo<T>::toobig(long long unsigned int)’:
test.cc:7: error: ‘T’ used where a ‘long long unsigned int’ was expected

The baffling part is that T doesn't occur anywhere in or near line 7.  It's
almost as if the initialization part of the static const member has been
textually substituted in line 7 -- but if it were that should still be legal... 

It works ok if I explicitly initialize the member outside the class definition
via specializations, which is tolerable given that only a small number of cases
of this template class are used.