Thank you for your answer!
I know the convolution operator is not supported for named tensors. It is just because  it is unsupported, there is no named tensors operator in my model. Hence, it is normal that this warning should not appear? But the warning appeared.
Or to say, is this warning bound to appear in the relatively recent version? But when I run the official demo app named HelloWorldApp, the warning doesn’t appear. Demo’s pytorch version and andriod library is 1.3.