I tried checking out that commit and rebuild pytorch and I am getting the following error.
x = torch.cat((self.pre_model(input1), self.pre_model(input2)), 1)
File “/anaconda2/lib/python2.7/site-packages/torch/nn/modules/module.py”, line 355, in call
result = self._slow_forward(*input, **kwargs)

File “/anaconda2/lib/python2.7/site-packages/torch/nn/modules/module.py”, line 345, in _slow_forward
result = self.forward(*input, **kwargs)

File “/anaconda2/lib/python2.7/site-packages/torch/nn/modules/container.py”, line 89, in forward
input = module(input)

File “/anaconda2/lib/python2.7/site-packages/torch/nn/modules/module.py”, line 355, in call
result = self._slow_forward(*input, **kwargs)

File “/anaconda2/lib/python2.7/site-packages/torch/nn/modules/module.py”, line 345, in _slow_forward
result = self.forward(*input, **kwargs)

File “/anaconda2/lib/python2.7/site-packages/torch/nn/modules/instancenorm.py”, line 24, in forward
eps=self.eps, affine=self.affine)

File “/anaconda2/lib/python2.7/site-packages/torch/nn/functional.py”, line 1209, in instance_norm
momentum=momentum, eps=eps, affine=affine)

File “/anaconda2/lib/python2.7/site-packages/torch/onnx/init.py”, line 392, in wrapper
"Passing Variable through kwargs is not supported"

AssertionError: Passing Variable through kwargs is not supported