Struct with `initializer_list` ctor inside union?

Question

I have a struct which is POD, but for convenience, I want it to have std::initializer_list ctor. Default ctor, copy ctor and dtor are implicit. It seems however that using initializer_list ctor disqualifies the struct as POD, hence it cannot be inside a union:

#include<initializer_list>
struct A{
   A(const std::initializer_list<int>&);
};

union{
   A a;
} a;

gcc 4.6 --std=c++0x:

error: use of deleted function ‘<anonymous union>::._0()’
error: ‘<anonymous union>::._0()’ is implicitly deleted because the default definition would be ill-formed:
error: no matching function for call to ‘A::A()’

Is there away around it? Is it related to the unrestricted unions feature of c++11?

Answer 1

The union itself must have an explicit ctor -- thanks to this article ):

union _u{
   A a;
   _u(){};
} a;