invalid use of brace-enclosed initializer list

I want to initialize the Foo class

class Foo {
public:
    struct MyStruct {
        uint8 i;
        char c;
    };

    Foo(MyStruct args...){

    };
};

But I'm getting a error

error: invalid use of brace-enclosed initializer list

auto test = Foo(
    {1, 'a'},
    {2, 'b'}
);

If I do this with variables, there is no error

Foo::MyStruct a1 = {1, 'a'};
Foo::MyStruct b2 = {2, 'b'};

auto test = Foo(a1, b2);

But I'm not comfortable with that, I'd like to make the code a compact