1 files changed, 2 insertions, 0 deletions
diff --git a/class.c b/class.c
index e6fb74816b..bb65ce487f 100644
--- a/class.c
+++ b/class.c
@@ -524,6 +524,7 @@ rb_define_class_id_under(VALUE outer, ID id, VALUE super)
     rb_set_class_path_string(klass, outer, rb_id2str(id));
     rb_const_set(outer, id, klass);
     rb_class_inherited(super, klass);
+    rb_gc_register_mark_object(klass);
 
     return klass;
 }
@@ -590,6 +591,7 @@ rb_define_module_id_under(VALUE outer, ID id)
     module = rb_define_module_id(id);
     rb_const_set(outer, id, module);
     rb_set_class_path_string(module, outer, rb_id2str(id));
+    rb_gc_register_mark_object(module);
 
     return module;
 }