Remove __torch_dispatch__ check in THPVariable_make_dtensor (#162337)

swolchok · pytorchmergebot · commit 1274297e0620 · 2025-09-11T06:58:35.000Z
We control DTensor, so we can just guarantee there isn't a programming error with __torch_dispatch__. (The guard is already less-than-perfect; see the note that the deleted comment refers to.) Pull Request resolved: #162337 Approved by: https://github.com/Skylion007 ghstack dependencies: #161591, #161595, #161633, #161634, #161692, #162219, #162220, #162218, #161596
diff --git a/torch/csrc/autograd/python_variable.cpp b/torch/csrc/autograd/python_variable.cpp
@@ -808,14 +808,18 @@ static PyObject* THPVariable_make_dtensor(
       "cls must be a type (got ",
       Py_TYPE(cls)->tp_name,
       ")");
-  // See note about the __torch_dispatch__ check in
-  // THPVariable_make_wrapper_subclass above.
+
+#ifndef NDEBUG
+  // This is specifically for making a DTensor, which we know defines
+  // __torch_dispatch__. Check anyway in debug builds in case somebody
+  // removes it.
   py::object attr = PyObject_FastGetAttrString(cls, "__torch_dispatch__");
   TORCH_CHECK_TYPE(
       attr.ptr() != nullptr &&
           attr.ptr() != torch::disabled_torch_dispatch_impl(),
       ((PyTypeObject*)cls)->tp_name,
       " must define __torch_dispatch__");
+#endif
 
   const auto& local_tensor = r.tensor(3);
   const auto options = TensorOptions()
