libstdc++: Simplify nullary _Flat_set_impl::_M_try_emplace overload Remove the unused template parameter pack _Args (which always gets deduced to an empty pack). libstdc++-v3/ChangeLog: * include/std/flat_set (_Flat_set_impl::_M_try_emplace): Turn nullary overload into a non-template. Reviewed-by: Jonathan Wakely <jwakely@redhat.com>