CHECK_CXX_SOURCE_COMPILES("#include <unordered_map>
                             int main() {
                               std::unordered_map<int, int> map;
                               return 0;
                             }"
                            HAVE_UNORDERED_MAP_IN_STD_NAMESPACE)

ELSE (HAVE_UNORDERED_MAP_IN_STD_NAMESPACE)

ENDIF (HAVE_UNORDERED_MAP_IN_STD_NAMESPACE)