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Consider the following code: template<class T> class Foo { public: Foo() { a = 1; } protected: int a; }; template<class T> class Bar : public Foo<T> { public: Bar() { b = 4; }; int Perna(int u); protected: int b; }; template<class T> int Bar<T>::Perna(int u) { int c = Foo<T>::a * 4; // This works return (a + b) * u; // This doesn't } g++ 3.4.6, 4.3.2 and 4.1.2 give error test.cpp: In member function `int Bar<T>::Perna(int)': test.cpp:25: error: `a' was not declared in this scope g++ 2.96 and MSVC 6, 7, 7.1, 8 and 9 accept it, as do (at least) older Intel and SGI c++ compilers. Do the new Gnu C++ compiler obey the standard or not? If they do, what is the rationale behind that inheriting class is not able to see a protected inherited member variable? Also, if there's int A() { return a; } in Foo, I get error test.cpp:25: error: there are no arguments to A that depend on a template parameter, so a declaration of A must be available test.cpp:25: error: (if you use -fpermissiveâ, G++ will accept your code, but allowing the use of an undeclared name is deprecated) when I try to use it in a member function of Bar. I find that curious as well: Bar inherits Foo, so I think it's obvious that A() in scope of Bar is Foo::A().

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