illegal memory access

[tkkcc]

I got this error when using this library to optimize flow, with lpips loss

RuntimeError: CUDA error: an illegal memory access was encountered

This problem maybe related to my loss, my torch version and cuda version, but I finally solved it by changing

Forward-Warp/Forward_Warp/cuda/forward_warp_cuda_kernel.cu

Line 176 in 91877f3

auto flow_grad = at::empty_like(flow);

to

  auto flow_grad = at::zeros_like(flow);

As in the backward_kernel function, only "not outside" position's flow_grad will be update, while "outside" position will remain the value inited by "empty_like". These parts are random values I think.