diff --git a/ChangeLog b/ChangeLog
index 6c22c9e6a9..2a2f69473a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Mar 12 08:14:48 2015  Koichi Sasada  <ko1@atdot.net>
+
+	* gc.c: RGENGC_CHECK_MODE should be 0.
+
 Thu Mar 12 07:44:17 2015  Koichi Sasada  <ko1@atdot.net>
 
 	* internal.h: use T_IMEMO to represent `struct MEMO' value.
diff --git a/gc.c b/gc.c
index ae9ed86023..9c9a268cd6 100644
--- a/gc.c
+++ b/gc.c
@@ -217,7 +217,7 @@ static ruby_gc_params_t gc_params = {
  * 5: show all references
  */
 #ifndef RGENGC_CHECK_MODE
-#define RGENGC_CHECK_MODE  2
+#define RGENGC_CHECK_MODE  0
 #endif
 
 /* RGENGC_PROFILE