sizeof in static const member initialization

Question

I have such code:

class A
{
public:

    unsigned long a;
    static const unsigned long b = sizeof(a); // \"error C2327: \'A::a\' : is not a type name, static,          


        

Answer 1

static const-qualified member in-class initialisers using non-static members were not part of the C++ standard until C++11.

The earliest MSVC compiler that fully supports C++11 is MSVC2017.

That compiler will compile your code correctly.