How to best way to construct a static class member in c++?

So simply put, I have a class Foo with a Foo() constructor.


Another class Bar which define a static member of class Foo: the Foo member is being initialized (but not constructed).


What's the best way to construct the static member, in other words where or how should I make sure the constructor is called on the static member?


Should I turn to singleton?
// In demo.h

class Foo {
Foo() {
// doing important stuff in there
}
};

class Bar {
static Foo foo;
};

// In demo.cpp
Foo Bar :: foo = Foo();

void main() {
Bar bar;

// bar.foo is not constructed yet. How to do that?
}