Summary: right now the log is just ``` RuntimeError: it != data_.modules_.end() INTERNAL ASSERT FAILED at "fbcode/caffe2/torch/csrc/jit/frontend/concrete_module_type.cpp":207, please report a bug to PyTorch. ``` we have no clue where the error happens https://fb.workplace.com/groups/gpuinference/posts/789257990578348/?comment_id=789284783909002&reply_comment_id=789415260562621 Test Plan: UT Reviewed By: jcwchen Differential Revision: D80020093 Pull Request resolved: https://github.com/pytorch/pytorch/pull/166192 Approved by: https://github.com/gmagogsfm