static (const) data members

[mcn]

trying to avoid using of Macros for declarations of the form

char u[MAXLEN];

because many old code in our departement was written before gcc was able to handle namespaces correctly, we used classes with static data members/methods instead. now we tried to port the following code to be used with VC++ 6.0

// a.hh
class A {
private:
  A() {}
  virtual ~A() {}

public:
  static const int a;
};

// a.cc
#include "a.h"

const int A::a = 7;

b.hh
class B {
public:
  B();
  virtual ~B() {}

};

// b.cc
#include "a.h"
#include "b.h"

B::B() 
{ 
  char u[A::a];  // error will occur here!!!
  std::cerr << "A::a is "   << A::a << std::endl; 
  std::cerr << "sizeof(u) is " << sizeof(u) << std::endl;
}

// test.cc
#include "b.h"

int main(int argc, char* argv[])
{
  B b;
  return 0;
}

things which works well with gcc yield the following the compiler errors using VC:

error C2057: expected constant expression
error C2466: cannot allocate an array of constant size 0
error C2133: 'u' : unknown size
error C2070: illegal sizeof operand

is this behaviour covered by the standard. i know that problems occur during dynamic initialization of A::a at runtime and its value may be undefined or 0 (statically initialized) but i never saw problems during compiletime.

mark