diff --git a/ChangeLog b/ChangeLog
index 0f6cdd5acd..1ce4169be3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Aug  3 01:20:19 2013  Tanaka Akira  <akr@fsij.org>
+
+	* bignum.c (bigadd_core): Removed.
+	  (bigadd): Use bary_add instead of bigadd_core.
+
 Sat Aug  3 00:52:43 2013  Tanaka Akira  <akr@fsij.org>
 
 	* bignum.c (rb_big2str1): Simplify power_level calculation.
diff --git a/bignum.c b/bignum.c
index faedade1e4..c31f480ed9 100644
--- a/bignum.c
+++ b/bignum.c
@@ -5357,12 +5357,6 @@ bigadd_int(VALUE x, long y)
     return bignorm(z);
 }
 
-static void
-bigadd_core(BDIGIT *xds, long xn, BDIGIT *yds, long yn, BDIGIT *zds, long zn)
-{
-    bary_add(zds, zn, xds, xn, yds, yn);
-}
-
 static VALUE
 bigadd(VALUE x, VALUE y, int sign)
 {
@@ -5383,9 +5377,9 @@ bigadd(VALUE x, VALUE y, int sign)
     }
     z = bignew(len, sign);
 
-    bigadd_core(BDIGITS(x), RBIGNUM_LEN(x),
-		BDIGITS(y), RBIGNUM_LEN(y),
-		BDIGITS(z), RBIGNUM_LEN(z));
+    bary_add(BDIGITS(z), RBIGNUM_LEN(z),
+             BDIGITS(x), RBIGNUM_LEN(x),
+             BDIGITS(y), RBIGNUM_LEN(y));
 
     return z;
 }