1 files changed, 11 insertions, 49 deletions
diff --git a/third_party/abseil-cpp/absl/meta/type_traits.h b/third_party/abseil-cpp/absl/meta/type_traits.h
index d886cb30a8..ba87d2f0ed 100644
--- a/third_party/abseil-cpp/absl/meta/type_traits.h
+++ b/third_party/abseil-cpp/absl/meta/type_traits.h
@@ -35,7 +35,7 @@
 #ifndef ABSL_META_TYPE_TRAITS_H_
 #define ABSL_META_TYPE_TRAITS_H_
 
-#include <cstddef>
+#include <stddef.h>
 #include <functional>
 #include <type_traits>
 
@@ -47,14 +47,6 @@
 #define ABSL_META_INTERNAL_STD_CONSTRUCTION_TRAITS_DONT_CHECK_DESTRUCTION 1
 #endif
 
-// Defines the default alignment. `__STDCPP_DEFAULT_NEW_ALIGNMENT__` is a C++17
-// feature.
-#if defined(__STDCPP_DEFAULT_NEW_ALIGNMENT__)
-#define ABSL_INTERNAL_DEFAULT_NEW_ALIGNMENT __STDCPP_DEFAULT_NEW_ALIGNMENT__
-#else  // defined(__STDCPP_DEFAULT_NEW_ALIGNMENT__)
-#define ABSL_INTERNAL_DEFAULT_NEW_ALIGNMENT alignof(std::max_align_t)
-#endif  // defined(__STDCPP_DEFAULT_NEW_ALIGNMENT__)
-
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
@@ -227,7 +219,7 @@ using void_t = typename type_traits_internal::VoidTImpl<Ts...>::type;
 // This metafunction is designed to be a drop-in replacement for the C++17
 // `std::conjunction` metafunction.
 template <typename... Ts>
-struct conjunction : std::true_type {};
+struct conjunction;
 
 template <typename T, typename... Ts>
 struct conjunction<T, Ts...>
@@ -236,6 +228,9 @@ struct conjunction<T, Ts...>
 template <typename T>
 struct conjunction<T> : T {};
 
+template <>
+struct conjunction<> : std::true_type {};
+
 // disjunction
 //
 // Performs a compile-time logical OR operation on the passed types (which
@@ -246,7 +241,7 @@ struct conjunction<T> : T {};
 // This metafunction is designed to be a drop-in replacement for the C++17
 // `std::disjunction` metafunction.
 template <typename... Ts>
-struct disjunction : std::false_type {};
+struct disjunction;
 
 template <typename T, typename... Ts>
 struct disjunction<T, Ts...> :
@@ -255,6 +250,9 @@ struct disjunction<T, Ts...> :
 template <typename T>
 struct disjunction<T> : T {};
 
+template <>
+struct disjunction<> : std::false_type {};
+
 // negation
 //
 // Performs a compile-time logical NOT operation on the passed type (which
@@ -507,27 +505,6 @@ struct is_trivially_copy_assignable
 #endif  // ABSL_HAVE_STD_IS_TRIVIALLY_ASSIGNABLE
 };
 
-#if defined(__cpp_lib_remove_cvref) && __cpp_lib_remove_cvref >= 201711L
-template <typename T>
-using remove_cvref = std::remove_cvref<T>;
-
-template <typename T>
-using remove_cvref_t = typename std::remove_cvref<T>::type;
-#else
-// remove_cvref()
-//
-// C++11 compatible implementation of std::remove_cvref which was added in
-// C++20.
-template <typename T>
-struct remove_cvref {
-  using type =
-      typename std::remove_cv<typename std::remove_reference<T>::type>::type;
-};
-
-template <typename T>
-using remove_cvref_t = typename remove_cvref<T>::type;
-#endif
-
 namespace type_traits_internal {
 // is_trivially_copyable()
 //
@@ -639,23 +616,8 @@ using common_type_t = typename std::common_type<T...>::type;
 template <typename T>
 using underlying_type_t = typename std::underlying_type<T>::type;
 
-
-namespace type_traits_internal {
-
-#if (defined(__cpp_lib_is_invocable) && __cpp_lib_is_invocable >= 201703L) || \
-    (defined(_MSVC_LANG) && _MSVC_LANG >= 201703L)
-// std::result_of is deprecated (C++17) or removed (C++20)
-template<typename> struct result_of;
-template<typename F, typename... Args>
-struct result_of<F(Args...)> : std::invoke_result<F, Args...> {};
-#else
-template<typename F> using result_of = std::result_of<F>;
-#endif
-
-}  // namespace type_traits_internal
-
-template<typename F>
-using result_of_t = typename type_traits_internal::result_of<F>::type;
+template <typename T>
+using result_of_t = typename std::result_of<T>::type;
 
 namespace type_traits_internal {
 // In MSVC we can't probe std::hash or stdext::hash because it triggers a