Fix osx cling

CMakeLists.txt

@@ -174,7 +174,7 @@ if( CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR )
   message(STATUS "Found supported version: Clang ${CLANG_PACKAGE_VERSION}")
   message(STATUS "Using ClangConfig.cmake in: ${Clang_DIR}")
 
-  ## Clang 13 require c++14 or later, Clang 16 require c++17 or later.
+  ## Clang 13 require c++14 or later (using 17 to allow c++17 attribute [[maybe_unused]] in tests), Clang 16 require c++17 or later.
   if (CLANG_VERSION_MAJOR GREATER_EQUAL 16)
     if (NOT CMAKE_CXX_STANDARD)
       set (CMAKE_CXX_STANDARD 17)
@@ -184,10 +184,10 @@ if( CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR )
     endif()
   elseif (CLANG_VERSION_MAJOR GREATER_EQUAL 13)
     if (NOT CMAKE_CXX_STANDARD)
-      set (CMAKE_CXX_STANDARD 14)
+      set (CMAKE_CXX_STANDARD 17)
     endif()
-    if (CMAKE_CXX_STANDARD LESS 14)
-      message(fatal "LLVM/CppInterOp requires c++14 or later")
+    if (CMAKE_CXX_STANDARD LESS 17)
+      message(fatal "LLVM/CppInterOp requires c++17 or later")
     endif()
   endif()
 
@@ -327,12 +327,6 @@ include_directories(BEFORE SYSTEM
 #Removes flag due to issue with Google test download when LLVM_ENABLE_WERROR=On
 string(REPLACE "-Wcovered-switch-default" "" CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")
 
-message(CXX_OPTS "${CMAKE_CXX_FLAGS}")
-message(MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS}")
-message(EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS}")
-message(SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS}")
-message(SHARED_LIBRARY_CREATE_CXX_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS}")
-
 file(STRINGS "VERSION" CPPINTEROP_VERSION)
 string(REGEX MATCH "([0-9]*)\.([0-9]*)\.([0-9]*)" CPPINTEROP_VERSION_ONLY "${CPPINTEROP_VERSION}")
 set(CPPINTEROP_VERSION_MAJOR "${CMAKE_MATCH_1}")
@@ -455,4 +449,4 @@ endif()
 add_subdirectory(lib)
 if (CPPINTEROP_ENABLE_TESTING)
   add_subdirectory(unittests)
-endif(CPPINTEROP_ENABLE_TESTING)
+endif(CPPINTEROP_ENABLE_TESTING)