diff --git a/sys/sys/libkern.h b/sys/sys/libkern.h
index e4a7880a46af..48fd4b17d486 100644
--- a/sys/sys/libkern.h
+++ b/sys/sys/libkern.h
@@ -77,15 +77,23 @@ void	*bsearch(const void *, const void *, size_t,
 #ifndef	HAVE_INLINE_FFS
 int	 ffs(int);
 #endif
+#if (__UINT_MAX == __ULONG_MAX)
+#define	 ffsl(x) ffs((x))
+#else
 #ifndef	HAVE_INLINE_FFSL
 int	 ffsl(long);
 #endif
+#endif
 #ifndef	HAVE_INLINE_FLS
 int	 fls(int);
 #endif
+#if (__UINT_MAX == __ULONG_MAX)
+#define	 flsl(x) fls((x))
+#else
 #ifndef	HAVE_INLINE_FLSL
 int	 flsl(long);
 #endif
+#endif
 int	 fnmatch(const char *, const char *, int);
 int	 locc(int, char *, u_int);
 void	 qsort(void *base, size_t nmemb, size_t size,