Compiler Warning (level 2) C4356

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'member' : static data member cannot be initialized via derived class

The initialization of a static data member was ill formed. The compiler accepted the initialization.

This is a breaking change in the Visual C++ .NET 2003 compiler. See Summary of Compile-Time Breaking Changes for more information.

For code that works the same in all versions of Visual C++, initialize the member through the base class.

Use the warning pragma to suppress this warning.

The following sample generates C4356:

// C4356.cpp
// compile with: /W2 /EHsc
#include <iostream>

template <class T>
class C {
   static int n;
};

class D : C<int> {};

int D::n = 0; // C4356
// try the following line instead
// int C<int>::n = 0;

class A {
public:
   static int n;
};

class B : public A {};

int B::n = 10;   // C4356
// try the following line instead
// int A::n = 99;

int main() {
   using namespace std;
   cout << B::n << endl;
}