From 97a419f5402e6a627a86b920d217ceeb21e56332 Mon Sep 17 00:00:00 2001
From: "Yukihiro \"Matz\" Matsumoto" <matz@ruby.or.jp>
Date: Tue, 13 Sep 2022 22:20:34 +0900
Subject: [PATCH] gc.c (clear_error_object): need to mark class of error
 objects; ref #5789

---
 src/gc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/gc.c b/src/gc.c
index 5a16ca742..4b8257c4b 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -1108,6 +1108,7 @@ clear_error_object(mrb_state *mrb, struct RObject *obj)
   if (obj == 0) return;
   if (!is_white(obj)) return;
   paint_black(obj);
+  mrb_gc_mark(mrb, (struct RBasic*)obj->c);
   mrb_gc_free_iv(mrb, obj);
   struct RException *err = (struct RException*)obj;
   err->iv = NULL;