diff options
Diffstat (limited to 'libstdc++-v3/include/std/variant')
| -rw-r--r-- | libstdc++-v3/include/std/variant | 34 |
1 files changed, 25 insertions, 9 deletions
diff --git a/libstdc++-v3/include/std/variant b/libstdc++-v3/include/std/variant index 2f44f97..f2f5583 100644 --- a/libstdc++-v3/include/std/variant +++ b/libstdc++-v3/include/std/variant @@ -393,8 +393,29 @@ namespace __variant _Variadic_union(in_place_index_t<_Np>, _Args&&...) = delete; }; - template<bool __trivially_destructible, typename _First, typename... _Rest> - union _Variadic_union<__trivially_destructible, _First, _Rest...> + template<typename _First, typename... _Rest> + union _Variadic_union<true, _First, _Rest...> + { + constexpr _Variadic_union() : _M_rest() { } + + template<typename... _Args> + constexpr + _Variadic_union(in_place_index_t<0>, _Args&&... __args) + : _M_first(in_place_index<0>, std::forward<_Args>(__args)...) + { } + + template<size_t _Np, typename... _Args> + constexpr + _Variadic_union(in_place_index_t<_Np>, _Args&&... __args) + : _M_rest(in_place_index<_Np-1>, std::forward<_Args>(__args)...) + { } + + _Uninitialized<_First> _M_first; + _Variadic_union<true, _Rest...> _M_rest; + }; + + template<typename _First, typename... _Rest> + union _Variadic_union<false, _First, _Rest...> { constexpr _Variadic_union() : _M_rest() { } @@ -410,24 +431,19 @@ namespace __variant : _M_rest(in_place_index<_Np-1>, std::forward<_Args>(__args)...) { } -#if __cpp_lib_variant >= 202106L _Variadic_union(const _Variadic_union&) = default; _Variadic_union(_Variadic_union&&) = default; _Variadic_union& operator=(const _Variadic_union&) = default; _Variadic_union& operator=(_Variadic_union&&) = default; - ~_Variadic_union() = default; - // If any alternative type is not trivially destructible then we need a // user-provided destructor that does nothing. The active alternative // will be destroyed by _Variant_storage::_M_reset() instead of here. - constexpr ~_Variadic_union() - requires (!__trivially_destructible) + _GLIBCXX20_CONSTEXPR ~_Variadic_union() { } -#endif _Uninitialized<_First> _M_first; - _Variadic_union<__trivially_destructible, _Rest...> _M_rest; + _Variadic_union<(is_trivially_destructible_v<_Rest> && ...), _Rest...> _M_rest; }; // _Never_valueless_alt is true for variant alternatives that can |