Usable case of pointer to array with unspecified bounds in C++ (not in C)

Question

Consider following code:

int main() {
    int (*p)[]; // pointer to array with unspecified bounds

    int a[] = {1};
    int b[] = {1,2};

    p = &a; /         


        

Answer 1

I think a compiler should accept it (irrespective of the -O setting) because a definition of the static can be provided by another compilation unit. (This is perhaps a pragmatic deviation from the standard - I'm not an C++ expert.) The posted snippet can be compiled, but it is incomplete and cannot be brought to execution without a definition of the static member.

File c.h:

struct C {
    static int v[];
};

File x.cpp

#include "c.h"
#include 
int main(){
    int (*p)[] = &C::v; // works in C++ if 'v' isn't defined (only declared)
    std::cout << (*p)[0] << std::endl; 
    return 0;
}

File y.cpp

#include "c.h"
int C::v[3] = {1,2,3};

Compiled and linked using (dont-tell-me-it's-old) g++ 4.3.3. Prints 1.