Do namespaces affect initialization order in C++?

Question

Global variables are initialized in order of appearing in the translation module and the relative order of initialization of variables in different translation modules in unspecified (so-called "static initialization order fiasco").

Do namespaces have any influence on that? For example if I have this code:

//first.cpp
int first;
int second;

will it have any difference in initialization order compared to this code:

//second.cpp
namespace {
int first;
}
int second;

Are there cases where putting a global object into a namespace affects initialization order?

Answer 1

3.6 Other non-local variables with static storage duration have ordered initialization. Variables with ordered initialization defined within a single translation unit shall be initialized in the order of their definitions in the translation unit.

Namespaces have no effect on this - not mentioned in the section.

What does effect the order is different translation units. If you need to define the order across them, use an extension such as GCC's constructor attribute.