1 files changed, 1 insertions, 0 deletions
diff --git a/eval.c b/eval.c
index 54ca11cfa6..47d968830b 100644
--- a/eval.c
+++ b/eval.c
@@ -9392,6 +9392,7 @@ Init_Binding(void)
     rb_undef_alloc_func(rb_cBinding);
     rb_undef_method(CLASS_OF(rb_cBinding), "new");
     rb_define_method(rb_cBinding, "clone", proc_clone, 0);
+    rb_define_method(rb_cBinding, "dup", proc_dup, 0);
     rb_define_method(rb_cBinding, "eval", bind_eval, -1);
     rb_define_global_function("binding", rb_f_binding, 0);
 }