PyTorch warnings: Tensor.data<T>() is deprecated.

[tomrunia]

After building both PyTorch and Apex from their master branches, my training script throws PyTorch C++ warnings at every training step. All warnings disappear when disabling Apex during training. Installing the official release of PyTorch 1.2 also seems to work without warnings.

/usr/local/lib/python3.5/dist-packages/torch/include/ATen/core/Tensor.h:297: UserWarning: Tensor.data<T>() is deprecated. Please use Tensor.data_ptr<T>() instead.
  TORCH_WARN("Tensor.data<T>() is deprecated. Please use Tensor.data_ptr<T>() instead.");

PyTorch from master: f622ec8084c1778c6943474796efa52e9b9cf695
Apex from master: 78c38db467c378759b4278a4ca8547763da5c91d
CUDA Toolkit: 10.1
CuDNN: 7.1

[mcarilli]

This looks annoying, I'll try to repro and fix.

In general we've learned it's annoying to ask users to install a repo separate from Pytorch, especially one that relies on extension builds. I've been focused on getting Amp upstream, to avoid all this in the future. pytorch/pytorch#25081.

The API will be different, as requested by upstream, but more flexible and powerful imo.

[mcarilli]

Should be fixed now, please reopen if it still shows deprecation warnings at either compile time or runtime.