https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69939
Bug ID: 69939 Summary: Ambiguous forward in experimental/tuple Product: gcc Version: 5.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libstdc++ Assignee: unassigned at gcc dot gnu.org Reporter: padhi at cs dot ucla.edu Target Milestone: --- In the line 57 of gcc/libstdc++-v3/include/experimental/tuple (from gcc-5-branch), `forward` should be `std::forward`: ``` template <typename _Fn, typename _Tuple, std::size_t... _Idx> constexpr decltype(auto) __apply_impl(_Fn&& f, _Tuple&& t, std::index_sequence<_Idx...>) { return std::forward<_Fn>(f)(get<_Idx>(forward<_Tuple>(t))...); } ``` (https://github.com/gcc-mirror/gcc/blob/gcc-5-branch/libstdc%2B%2B-v3/include/experimental/tuple#L57)