diff --git a/ChangeLog b/ChangeLog
index 6f2a7156aa..12f7836634 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Jul 14 00:36:03 2013  Tanaka Akira  <akr@fsij.org>
+
+	* bignum.c (DIGSPERLONG): Unused macro removed.
+	  (DIGSPERLL): Ditto.
+
 Sun Jul 14 00:32:51 2013  Tanaka Akira  <akr@fsij.org>
 
 	* bignum.c (rb_big_aref): Less scan when the number is negative.
diff --git a/bignum.c b/bignum.c
index 9a4d032e42..0585600dd9 100644
--- a/bignum.c
+++ b/bignum.c
@@ -65,12 +65,6 @@ STATIC_ASSERT(rbignum_embed_len_max, RBIGNUM_EMBED_LEN_MAX <= (RBIGNUM_EMBED_LEN
 #define BIGRAD ((BDIGIT_DBL)1 << BITSPERDIG)
 #define BIGRAD_HALF ((BDIGIT)(BIGRAD >> 1))
 #define BDIGIT_MSB(d) (((d) & BIGRAD_HALF) != 0)
-#if SIZEOF_LONG >= SIZEOF_BDIGITS
-#   define DIGSPERLONG (SIZEOF_LONG/SIZEOF_BDIGITS)
-#endif
-#if defined(HAVE_LONG_LONG) && SIZEOF_LONG_LONG >= SIZEOF_BDIGITS
-# define DIGSPERLL (SIZEOF_LONG_LONG/SIZEOF_BDIGITS)
-#endif
 #define BIGUP(x) LSHIFTX(((x) + (BDIGIT_DBL)0), BITSPERDIG)
 #define BIGDN(x) RSHIFT((x),BITSPERDIG)
 #define BIGLO(x) ((BDIGIT)((x) & BDIGMAX))