Are all constexpr variable implicitly inline?

Question

I was playing around with auto template parameters and I was surprised that this code didn\'t compiled:

constexpr auto bar = 2;

template

        

Answer 1

Are all constexpr variable implicitly inline?

No. Only constexpr functions and constexpr static data members are implicitly inline ([dcl.constexpr]/1).

Also, how does that affect the linkage of my variable bar?

A constexpr variable is const ([dcl.constexpr]/9). A non-inline const variable that is not explicitly declared extern has internal linkage ([basic.link]/3).