diff --git a/ChangeLog b/ChangeLog
index 4d9806878b..bb4c1e70bb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Oct 29 14:07:54 2015  Koichi Sasada  <ko1@atdot.net>
+
+	* gc.c (gc_mark_ptr): remove debug code for #11244.
+
 Thu Oct 29 10:08:33 2015  Eric Wong  <e@80x24.org>
 
 	* variable.c (struct autoload_state): usable as wait-queue head
diff --git a/gc.c b/gc.c
index 4e9df0cd68..bdab8d8f4c 100644
--- a/gc.c
+++ b/gc.c
@@ -4235,17 +4235,6 @@ static void
 gc_mark_ptr(rb_objspace_t *objspace, VALUE obj)
 {
     if (LIKELY(objspace->mark_func_data == NULL)) {
-	/* check code for Bug #11244 */
-	if (BUILTIN_TYPE(obj) == T_NONE) {
-	    if (objspace->rgengc.parent_object) {
-		rb_bug("gc_mark_ptr: obj is %s (parent: %s)", obj_info(obj),
-		       obj_info(objspace->rgengc.parent_object));
-	    }
-	    else {
-		rb_bug("gc_mark_ptr: obj is %s (parent is not old)", obj_info(obj));
-	    }
-	}
-
 	rgengc_check_relation(objspace, obj);
 	if (!gc_mark_set(objspace, obj)) return; /* already marked */
 	gc_aging(objspace, obj);