I used conda to create a new virtual environment and installed the latest nightly build. It seems that this issue still occurs.
System: macOS Mojave 10.14.1
Python: 3.7.1
PyTorch: 1.0.0.dev20181227
>>> import torch
>>> print(torch.__version__)
1.0.0.dev20181227
>>> x = (torch.randn(4,4) * 10).long()
>>> x
tensor([[  4,  -6,   7,  -2],
        [-10,  -2,  13,   0],
        [  1,  -4, -17,   3],
        [  4,   2, -10,  -9]])
>>> torch.relu(x)
tensor([[  0,  -6,   0,  -2],
        [-10,  -2,   0,   0],
        [  0,  -4, -17,   0],
        [  0,   0, -10,  -9]])