How to brace initialize a std::stack in C++?

Question

I have a struct, one of whose members is a std::stack using a std::array as its underlying container:

struct S {
  int a, b; // dummy members
  std::stack<
    int, 
    std::array<int, 10>
  > st;
};

I would like to use brace initialization to initialize all members of an S struct, something like:

S const obj {
  1, // a
  2, // b
  {1, 2, 3} /* st
         ^
         I want this at the top of the stack */
};

Is this kind of initialization possible for std::stack? If yes, what would the syntax be?