-SET(LIBBATCH_NO_CXX11_SUPPORT FALSE CACHE BOOL "Switch OFF C++-11 standard")
-IF(NOT LIBBATCH_NO_CXX11_SUPPORT)
- # C++11 support
- CHECK_CXX_COMPILER_FLAG("-std=c++11" COMPILER_SUPPORTS_CXX11)
- IF(COMPILER_SUPPORTS_CXX11)
- MESSAGE(STATUS "Enable C++11 support")
- SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
- ELSE()
- CHECK_CXX_COMPILER_FLAG("-std=c++0x" COMPILER_SUPPORTS_CXX0X)
- IF(COMPILER_SUPPORTS_CXX0X)
- MESSAGE(STATUS "Enable C++0x support")
- SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++0x")
- ELSE()
- MESSAGE(WARNING "Compiler ${CMAKE_CXX_COMPILER} has no C++11 support.")
- ENDIF()
- ENDIF()
+# Option: C++ standard to use
+# Note: CMake by default enables C++ extensions; they can be disabled by additionally
+# specifying -DCMAKE_CXX_EXTENSIONS=OFF
+CMAKE_POLICY(SET CMP0057 NEW) # for IF(IN_LIST) operator
+SET(LIBBATCH_CXX_STANDARD 11 CACHE STRING "C++ standard to use")
+SET(_supported_standards 11 14 17 20)
+IF(NOT ${LIBBATCH_CXX_STANDARD} IN_LIST _supported_standards)
+ MESSAGE(FATAL_ERROR "Unsupported C++ standard: ${LIBBATCH_CXX_STANDARD}; allowed values: ${_supported_standards}")