diff --git a/ChangeLog b/ChangeLog
index 471a0608cf..f058a7b002 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Jul 12 12:24:29 2007  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* insns.def (opt_succ): fixed typo.  [ruby-dev:31189]
+
 Thu Jul 12 10:30:46 2007  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* thread.c (thread_start_func_2): moved prototye from thread_*.ci.
diff --git a/insns.def b/insns.def
index be67ab09e4..9116430f28 100644
--- a/insns.def
+++ b/insns.def
@@ -2305,8 +2305,8 @@ opt_succ
 	    /* fixnum + INT2FIX(1) */
 	    val = (recv + (obj & (~1)));
 	    if ((~(recv ^ obj) & (recv ^ val)) & 0x80000000) {
-		val = rb_big_plus(rb_int2big(INT2FIX(recv)),
-				  rb_int2big(INT2FIX(obj)));
+		val = rb_big_plus(rb_int2big(FIX2INT(recv)),
+				  rb_int2big(FIX2INT(obj)));
 	    }
 	}
 	else {