Hi,
Each cat operation is append-only modification. All concatenated tensors are already written in the buffer, and we just add a new (previous Linear) result to the right of buffer.
So, when you say " the previous linear won’t have access to the value it needs to compute the backward", do you mean that buffer for this linear will be changed in future (it won’t, as i said) or that it will magically “disappear” from autograd internals due to some code specifity?
Considering Python error - i’ll check out master branch and try it, thank you!