1 files changed, 3 insertions, 0 deletions
diff --git a/src/gc.c b/src/gc.c
index 8cc8feb08..cd885f7e8 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -647,6 +647,9 @@ gc_mark_children(mrb_state *mrb, mrb_gc *gc, struct RBasic *obj)
 
       mrb_gc_mark(mrb, (struct RBasic*)p->env);
       mrb_gc_mark(mrb, (struct RBasic*)p->target_class);
+      if (!MRB_PROC_CFUNC_P(p)) {
+        mrb_gc_mark(mrb, (struct RBasic*)p->body.irep->outer);
+      }
     }
     break;