_generic_isCC(c, _CC_NON_FINAL_FOLD)
# define _IS_IN_SOME_FOLD_ONLY_FOR_USE_BY_REGCOMP_DOT_C(c) \
_generic_isCC(c, _CC_IS_IN_SOME_FOLD)
-# define _IS_MNEMONIC_CNTRL_ONLY_FOR_USE_BY_REGCOMP_DOT_C(c) \
- _generic_isCC(c, _CC_MNEMONIC_CNTRL)
+
+/* is c a control character for which we have a mnemonic? */
+# if defined(PERL_CORE) || defined(PERL_EXT)
+# define isMNEMONIC_CNTRL(c) _generic_isCC(c, _CC_MNEMONIC_CNTRL)
+# endif
#else /* else we don't have perl.h H_PERL */
/* If we don't have perl.h, we are compiling a utility program. Below we