1 files changed, 1 insertions, 1 deletions
diff --git a/array.c b/array.c
index 65fd0b6268..4e60177121 100644
--- a/array.c
+++ b/array.c
@@ -4583,7 +4583,7 @@ flatten(VALUE ary, int level, int *modified)
 
     st_free_table(memo);
 
-    RBASIC_SET_CLASS(result, rb_class_of(ary));
+    RBASIC_SET_CLASS(result, rb_obj_class(ary));
     return result;
 }