diff --git a/m4/nc_cxx.m4 b/m4/nc_cxx.m4
index b7faa3b7..9f4d064a 100644
--- a/m4/nc_cxx.m4
+++ b/m4/nc_cxx.m4
@@ -14,14 +14,5 @@ AC_DEFUN([NC_CXX],[
     AC_C_RESTRICT
     AC_C_INLINE
 
-    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([struct A     { virtual void C (void) = 0;  };
-                                        struct B : A { void C (void) override; }; ],
-                                       [])],
-                      [], [AC_DEFINE([override], [], [Pretend about override keyword support])])
-
-    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([struct A final { }; ],
-                                       [])],
-                      [], [AC_DEFINE([final], [], [Pretend about final keyword support])])
-
     AX_APPEND_COMPILE_FLAGS([-fvisibility=hidden], [], [-Werror])
 ])