diff --git a/ChangeLog b/ChangeLog
index b8de0b96c6..850483473a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sat Aug 15 04:16:13 2015  Eric Wong  <e@80x24.org>
+
+	* iseq.c (rb_iseq_mark): reduce NULL checks
+
 Fri Aug 14 18:50:57 2015  Eric Wong  <e@80x24.org>
 
 	* method.h (METHOD_ENTRY_VISI_SET): cast visi to int
diff --git a/iseq.c b/iseq.c
index e9b84a1589..9b32c0a20d 100644
--- a/iseq.c
+++ b/iseq.c
@@ -108,9 +108,9 @@ rb_iseq_mark(const rb_iseq_t *iseq)
 	const struct rb_iseq_constant_body *body = iseq->body;
 
 	RUBY_MARK_UNLESS_NULL(body->mark_ary);
-	RUBY_MARK_UNLESS_NULL(body->location.label);
-	RUBY_MARK_UNLESS_NULL(body->location.base_label);
-	RUBY_MARK_UNLESS_NULL(body->location.path);
+	rb_gc_mark(body->location.label);
+	rb_gc_mark(body->location.base_label);
+	rb_gc_mark(body->location.path);
 	RUBY_MARK_UNLESS_NULL(body->location.absolute_path);
     }