trait detecting anonymous union?

[Bastiaan Veelo via Digitalmars-d-learn]

`
void main()
{
        import std.stdio;
        struct S
        {
                int i;
                union
                {
                        int a;
                        double b;
                }
        }
        S s;
        writeln(s);                  // S(10, #{overlap a, b})
        import std.traits;
        writeln([FieldNameTuple!S]); // ["i", "a", "b"]
}
`
Is there a way to detect at CT that S has overlapping data 
members, when an anonimous union is used as above?

Thanks,
Bastiaan.