Hi there,
I am trying to use a torch script exported module traced on iOS device but I am getting this error:
ibc++abi.dylib: terminating with uncaught exception of type torch::jit::ErrorReport: 
Unknown builtin op: aten::_batch_norm_impl_index_backward.
Could not find any similar ops to aten::_batch_norm_impl_index_backward. This op may not exist or may not be currently supported in TorchScript.
:
  File "<string>", line 19

            def backward(grad_output):
                dinput, dweight, dbias = torch._batch_norm_impl_index_backward(
                                         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ <--- HERE
                    impl_idx, input, grad_output, weight, running_mean, running_var,
                    save1, save2, training, eps, [True, has_weight, has_bias], reserve)


This only occurs when loading the traced script on mobile. Using a desktop platform runs ok.
I have read a related issue pytorch repository issue 9 but it seems that it does not fix the problem in this case.
Could anyone help me with this?
Thanks