diff --git a/include/xlocale/_ctype.h b/include/xlocale/_ctype.h
index 1fdebd6d73e..aaad8da5418 100644
--- a/include/xlocale/_ctype.h
+++ b/include/xlocale/_ctype.h
@@ -88,6 +88,11 @@ __istype_l(__ct_rune_t __c, unsigned long __f, locale_t __loc)
 		_XLOCALE_INLINE int isw##fname##_l(int __c, locale_t __l)\
 		{ return __istype_l(__c, cat, __l); }
 #else
+_XLOCALE_INLINE int
+__sbmaskrune_l(__ct_rune_t __c, unsigned long __f, locale_t __loc);
+_XLOCALE_INLINE int
+__sbistype_l(__ct_rune_t __c, unsigned long __f, locale_t __loc);
+
 _XLOCALE_INLINE int
 __sbmaskrune_l(__ct_rune_t __c, unsigned long __f, locale_t __loc)
 {