use C++17 if available when configuring with cmake

build/CMakeLists.txt

@@ -184,16 +184,16 @@ else()
   set( CMAKE_EXE_LINKER_FLAGS_MINSIZEREL "-Wl,--gc-sections" ) # -flto is added from above
 endif ()
 
-# check for c++11 support
+# check for c++17 & c++11 support
 include(CheckCXXCompilerFlag)
+CHECK_CXX_COMPILER_FLAG("-std=c++17" CXX17_SUPPORTED)
 CHECK_CXX_COMPILER_FLAG("-std=c++11" CXX11_SUPPORTED)
-CHECK_CXX_COMPILER_FLAG("-std=c++0x" CXX0X_SUPPORTED)
-if (CXX11_SUPPORTED)
+if (CXX17_SUPPORTED)
+  set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17" )
+elseif (CXX11_SUPPORTED)
   set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11" )
-elseif (CXX0X_SUPPORTED) # gcc 4.6
-  set( CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x" )
-elseif (NOT MSVC)
-  message(SEND_ERROR "C++11 standard not seems to be supported by compiler. Too old version?")
+else
+  message(SEND_ERROR "C++17 nor C++11 standard not seems to be supported by compiler. Too old version?")
 endif ()
 
 if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")