-# For some reason the above flags don't really work...
-if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR CMAKE_COMPILER_IS_GNUCXX)
- include(CheckCXXCompilerFlag)
- check_cxx_compiler_flag(--std=c++${CMAKE_CXX_STANDARD} STD_CXX)
- if (STD_CXX)
- set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} --std=c++${CMAKE_CXX_STANDARD}")
+if (CMAKE_VERSION VERSION_LESS "3.1")
+ if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang" OR CMAKE_COMPILER_IS_GNUCXX)
+ include(CheckCXXCompilerFlag)
+ check_cxx_compiler_flag(--std=c++${CMAKE_CXX_STANDARD} STD_CXX)
+ if (STD_CXX)
+ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} --std=c++${CMAKE_CXX_STANDARD}")
+ else ()
+ message(SEND_ERROR "Requires C++${CMAKE_CXX_STANDARD} or better")
+ endif ()