diff --git a/ChangeLog b/ChangeLog
index ae727c3150..6f5590e81d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Fri Sep  2 16:06:59 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* internal.h (MEMO_V1_SET, MEMO_V2_SET): fix typos.  use the macro
+	  parameter, not the local variable.
+
 Fri Sep  2 00:55:11 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* ext/extmk.rb (timestamp_file): move extmk.rb specific tricks
diff --git a/internal.h b/internal.h
index 7088deb706..f9bc693e0f 100644
--- a/internal.h
+++ b/internal.h
@@ -812,8 +812,8 @@ struct MEMO {
     } u3;
 };
 
-#define MEMO_V1_SET(m, v) RB_OBJ_WRITE((memo), &(memo)->v1, (v))
-#define MEMO_V2_SET(m, v) RB_OBJ_WRITE((memo), &(memo)->v2, (v))
+#define MEMO_V1_SET(m, v) RB_OBJ_WRITE((m), &(m)->v1, (v))
+#define MEMO_V2_SET(m, v) RB_OBJ_WRITE((m), &(m)->v2, (v))
 
 #define MEMO_CAST(m) ((struct MEMO *)m)