diff --git a/load.c b/load.c
index b0143b7b82..cb3a6c03b1 100644
--- a/load.c
+++ b/load.c
@@ -1234,7 +1234,7 @@ static VALUE
 rb_f_autoload(VALUE obj, VALUE sym, VALUE file)
 {
     VALUE klass = rb_class_real(rb_vm_cbase());
-    if (NIL_P(klass)) {
+    if (!klass) {
 	rb_raise(rb_eTypeError, "Can not set autoload on singleton class");
     }
     return rb_mod_autoload(klass, sym, file);