[Mingw-users] Code C++ not compile in MinGW

[Георгий Ф. <ab...@ma...>]

Hello. When I compile this code

#include <cstdlib>
#include <iostream>

template <class Type> class Number {
protected:
    Type value;
public:
    Number(Type valueV) {
        value = valueV;
    }
    virtual Type getValue() {
        return value;
    } 
};

template <class Type> class Sqr : public Number<Type> {
public:
    Sqr(Type valueV) : Number<Type>(valueV) {}
    Type getValue() {
        return value * value;
    }
};

int main(int argc, char** argv) {
    Sqr<int> obSqrInt (20);
    std::cout << "obSqrInt.getValue() " << obSqrInt.getValue() << "\n";
    return 0;
}


 in MinGw, I get 

E:\Test>g++ -o a test.cpp
test.cpp: In member function 'Type Sqr<Type>::getValue()':
test.cpp:21:16: error: 'value' was not declared in this scope

When I compile and run this code in Visual c++, I get

obSqrInt.getValue() 400

Explain me, please, why MinGW not compile this code.

With best reguards, George, from Kiev