Implement P0298R3: 'std::byte'. Reviewed as https://reviews.llvm.org/D31022
llvm-svn: 298689
diff --git a/libcxx/include/cstddef b/libcxx/include/cstddef
index 103898b..6258449 100644
--- a/libcxx/include/cstddef
+++ b/libcxx/include/cstddef
@@ -28,6 +28,7 @@
size_t
max_align_t
nullptr_t
+ byte // C++17
} // std
@@ -58,4 +59,32 @@
_LIBCPP_END_NAMESPACE_STD
+#if _LIBCPP_STD_VER > 14
+namespace std // purposefully not versioned
+{
+enum class byte : unsigned char {};
+
+constexpr byte& operator|=(byte& __lhs, byte __rhs) noexcept
+{ return __lhs = byte(static_cast<unsigned char>(__lhs) | static_cast<unsigned char>(__rhs)); }
+constexpr byte operator| (byte __lhs, byte __rhs) noexcept
+{ return byte(static_cast<unsigned char>(__lhs) | static_cast<unsigned char>(__rhs)); }
+
+constexpr byte& operator&=(byte& __lhs, byte __rhs) noexcept
+{ return __lhs = byte(static_cast<unsigned char>(__lhs) & static_cast<unsigned char>(__rhs)); }
+constexpr byte operator& (byte __lhs, byte __rhs) noexcept
+{ return byte(static_cast<unsigned char>(__lhs) & static_cast<unsigned char>(__rhs)); }
+
+constexpr byte& operator^=(byte& __lhs, byte __rhs) noexcept
+{ return __lhs = byte(static_cast<unsigned char>(__lhs) ^ static_cast<unsigned char>(__rhs)); }
+constexpr byte operator^ (byte __lhs, byte __rhs) noexcept
+{ return byte(static_cast<unsigned char>(__lhs) ^ static_cast<unsigned char>(__rhs)); }
+
+constexpr byte operator~ (byte __b) noexcept
+{ return byte(~static_cast<unsigned char>(__b)); }
+
+}
+
+#include <type_traits> // rest of byte
+#endif
+
#endif // _LIBCPP_CSTDDEF