InPlaceABNSync error in torch=0.4.0, and inplace_abn.so error in torch=0.4.1

[Ximoi]

hi ,the InPlaceABNSync seems not working, when I use pytorch=0.4.0 , the testing process was stuck in the bn layer (functools.partial(InPlaceABNSync, activation='none')):
https://github.com/HRNet/HRNet-Semantic-Segmentation/blob/master/lib/models/seg_hrnet.py#L269
When I use pytorch=0.4.1, the bug is different as follows:

File "tools/test.py", line 25, in
import models
File "/home/fuyi02/vos/HRNet-Semantic-Segmentation/tools/../lib/models/init.py", line 11, in
import models.seg_hrnet
File "/home/fuyi02/vos/HRNet-Semantic-Segmentation/tools/../lib/models/seg_hrnet.py", line 22, in
from .sync_bn.inplace_abn.bn import InPlaceABNSync
File "/home/fuyi02/vos/HRNet-Semantic-Segmentation/tools/../lib/models/sync_bn/init.py", line 1, in
from .inplace_abn import bn
File "/home/fuyi02/vos/HRNet-Semantic-Segmentation/tools/../lib/models/sync_bn/inplace_abn/init.py", line 1, in
from .bn import ABN, InPlaceABN, InPlaceABNSync
File "/home/fuyi02/vos/HRNet-Semantic-Segmentation/tools/../lib/models/sync_bn/inplace_abn/bn.py", line 14, in
from functions import *
File "/home/fuyi02/vos/HRNet-Semantic-Segmentation/lib/models/sync_bn/inplace_abn/functions.py", line 16, in
extra_cuda_cflags=["--expt-extended-lambda"])
File "/home/fuyi02/anaconda3/envs/HRNet/lib/python3.6/site-packages/torch/utils/cpp_extension.py", line 514, in load
with_cuda=with_cuda)
File "/home/fuyi02/anaconda3/envs/HRNet/lib/python3.6/site-packages/torch/utils/cpp_extension.py", line 690, in _jit_compile
return _import_module_from_library(name, build_directory)
File "/home/fuyi02/anaconda3/envs/HRNet/lib/python3.6/site-packages/torch/utils/cpp_extension.py", line 773, in _import_module_from_library
return imp.load_module(module_name, file, path, description)
File "/home/fuyi02/anaconda3/envs/HRNet/lib/python3.6/imp.py", line 243, in load_module
return load_dynamic(name, filename, file)
File "/home/fuyi02/anaconda3/envs/HRNet/lib/python3.6/imp.py", line 343, in load_dynamic
return _load(spec)
ImportError: /tmp/torch_extensions/inplace_abn/inplace_abn.so: undefined symbol: _ZN2at5ErrorC1ENS_14SourceLocationESs

How to fix this bug?