struct Base
{
   static int x;
}

int Base::x = 1;
and in file b.hpp, we have a struct
struct Derived: Base
{
   static int y;
}

int Derived::y = 2;
Is it guaranteed that when we compile these two class file, static
variable x will be initialized before static variable y?
I know that initialization of static variables are not defined, but
since x is in a base class, will it be first initialized?


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Am 23.04.2011 21:34, schrieb aakash:
> struct Base
> {
>     static int x;
> }
>
> int Base::x = 1;
> and in file b.hpp, we have a struct
> struct Derived: Base
> {
>     static int y;
> }
>
> int Derived::y = 2;
> Is it guaranteed that when we compile these two class file, static
> variable x will be initialized before static variable y?
> I know that initialization of static variables are not defined, but
> since x is in a base class, will it be first initialized?

Initialization order of variables of static storage duration is
specified for many situations *if* the variables are defined in the same
translation unit. Your description does not really say whether
Base::x and Derived::y are defined in the same translation unit. Both
initializations are so-called static-initializations (more specifically:
They are constant initializations), so it depends solely on the relative
points of definitions in the same translation unit to decide on the
order. In this case I don't see how you could observe a difference,
because both initializations are independent from each other.

There does *not* exist any rule that involves base-derived relationships
for static data members, so you cannot rely on such relations, if you
have a situations where both variables are defined in different
translation units.

HTH & Greetings from Bremen,

Daniel Kr   gler


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