Static pointer to class member causes undefined reference

Asked Dec 15 '16 at 16:23

Active Dec 15 '16 at 16:23

Viewed 20 times

SSCCE of my problem is:

class Callee
{
public:
  int m1()
  {
    return 5;
  }

  constexpr static int (Callee::*method)() = &Callee::m1;
};

template <class O> int call(O &o, int (O::*m)())
{
  return (o.*m)();
}

int main()
{
  Callee callee;
  return
    (callee.*Callee::method)() // works fine
    *
    call<Callee>(callee, Callee::method) // causes undefined reference in GCC
  ;
}

This code compiled in clang (3.4-1) but failed in gcc (4.8.4) with message:

undefined reference to `Callee::method'

Shorter, I can call some class method by its pointer directly, but I can't call it from templated function. (It is more unclear, than I inherit from Callee, because both methods works fine) Why?

asked Dec 15 '16 at 16:23

dyomas

1

Note that the code is well formed and link property in C++17, since `static constexpr` data member are inlined by default. – Guillaume Racicot Dec 15 '16 at 18:56
@Guillaume, Did you mean «properLy»? – dyomas Dec 16 '16 at 08:16
yes. I guess I hit muscle memory – Guillaume Racicot Dec 16 '16 at 13:43

Static pointer to class member causes undefined reference

0 Answers0