Namespace using declaration (bug in GCC/VS2010)?

Question

namespace A{
   int i;
}

int main(){
   using A::i;
   using A::i;
}

VS2010 - compiles fine

gcc (ideone) - compiles fine

Comeau -

Answer 1

Yes you are right. This is indeed a bug in g++, MSVC++ and Clang. Comeau has got it correct.

As you said 7.3.3/8 says

A using-declaration is a declaration and can therefore be used repeatedly where (and only where) multiple declarations are allowed

The following code snippet is also given.

void f()
{
    using A::i;
    using A::i;  //error: double declaration
}

Similarly your code is ill-formed too.