1 files changed, 1 insertions, 1 deletions
diff --git a/iseq.c b/iseq.c
index 774aafadda..1af491e997 100644
--- a/iseq.c
+++ b/iseq.c
@@ -229,7 +229,7 @@ set_relation(rb_iseq_t *iseq, const VALUE parent)
 }
 
 void
-rb_iseq_add_mark_object(rb_iseq_t *iseq, VALUE obj)
+rb_iseq_add_mark_object(const rb_iseq_t *iseq, VALUE obj)
 {
     if (!RTEST(iseq->mark_ary)) {
 	RB_OBJ_WRITE(iseq->self, &iseq->mark_ary, rb_ary_tmp_new(3));