Question

I had a problem, which I eventually reduced down to this simple example:

template <int dimensions> class Base {
    protected:
        Base(void) {}
    public:
        virtual ~Base(void) {}

        void base_method(void) {}
};
template <int dimensions> class MyClass : public Base<dimensions> {
    public:
        MyClass(void) : Base<dimensions>() {
            base_method();
        }
        ~MyClass(void) {}
};

This compiles fine on MSVC 2010, but fails with g++ 4.6:

main2.cpp: In constructor âMyClass<dimensions>::MyClass()â:
main2.cpp:12:16: error: there are no arguments to âbase_methodâ that depend on a template parameter, so a declaration of âbase_methodâ must be available [-fpermissive]
main2.cpp:12:16: note: (if you use â-fpermissiveâ, G++ will accept your code, but allowing the use of an undeclared name is deprecated)

What’s going on?

Answer 1

you have to do:

this->base_method();

or

Base<dimension>::base_method();

Compilers generally will not consider methods in templated base class for function resolution.