https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69958
Ibrahim Gokhan YANIKLAR <yanikibo at yandex dot com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |yanikibo at yandex dot com --- Comment #2 from Ibrahim Gokhan YANIKLAR <yanikibo at yandex dot com> --- #include <iostream> template < std::size_t N > struct A { enum : std::size_t { value = N }; }; template < class... TL > using B = A< sizeof...(TL) >; template < class T > struct C { using type = T; }; template < class... TL > using D = typename C< B<TL...> >::type; template < class T, class U, class... TL > void foo( T, U, TL... ) { std::cout << (B<T, U, TL...>::value) << std::endl; std::cout << (D<T, U, TL...>::value) << std::endl; std::cout << (C< B<T, U, TL...> >::type::value) << std::endl; } int main() { foo(10, 20, 30, 40, 50); } //----------------------- // output(g++4.7): //----------------------- // 3 // 3 // 3 //----------------------- // output(g++4.8-g++5.3): //----------------------- // 5 // 5 // 3 //----------------------- // output(correct) //----------------------- // 5 // 5 // 5