[CMake] Use C++17

rpcs3/CMakeLists.txt

@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.1)
 
 set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_LIST_DIR}/cmake_modules")
 set(RES_FILES "")
-set(CMAKE_CXX_STANDARD 14)
+set(CMAKE_CXX_STANDARD 17)
 include(CheckCXXCompilerFlag)
 
 # Qt section

rpcs3/Emu/RSX/rsx_utils.h

@@ -6,14 +6,7 @@
 #include <atomic>
 #include <memory>
 #include <bitset>
-
-// TODO: replace the code below by #include <optional> when C++17 or newer will be used
-#include <optional.hpp>
-namespace std
-{
-	template<class T>
-	using optional = experimental::optional<T>;
-}
+#include <optional>
 
 extern "C"
 {

rpcs3/stdafx.h

@@ -45,13 +45,3 @@ namespace std { inline namespace literals { inline namespace chrono_literals {}}
 #include <algorithm>
 
 using namespace std::literals;
-
-// Remove once we move to C++17
-namespace std
-{
-	template<typename T>
-	constexpr const T clamp(const T value, const T min, const T max)
-	{
-		return value < min ? min : value > max ? max : value;
-	}
-}