Description of the problem / feature request / question:

Whole day "bazel build" command fails. From logs I see that it compares check sum '@protobuf//' and they do not match. I've tried it on several machines - had same error.

If possible, provide a minimal example to reproduce the problem:

git clone https://github.com/tensorflow/tensorflow.git
cd tensorflow
./configure
bazel build --config=opt //tensorflow/tools/pip_package:build_pip_package

Environment info

• Operating System: Ubuntu 16.04

• Bazel version (output of bazel info release): release 0.5.2 (also tried 0.5.3, 0.5.4 - had same result)

Anything else, information or logs or outputs that would be helpful?

`
oleksandrmalinin@oleksandrmalinin:~/serving/tensorflow$ bazel build -c opt tensorflow/python/tools:freeze_graph
ERROR: /home/oleksandrmalinin/serving/tensorflow/tensorflow/python/tools/BUILD:32:1: error loading package 'tensorflow/core': Encountered error while reading extension file 'protobuf.bzl': no such package '@protobuf//': java.io.IOException: Error downloading [https://github.com/google/protobuf/archive/0b059a3d8a8f8aa40dde7bea55edca4ec5dfea66.tar.gz, http://mirror.bazel.build/github.com/google/protobuf/archive/0b059a3d8a8f8aa40dde7bea55edca4ec5dfea66.tar.gz] to /home/oleksandrmalinin/.cache/bazel/_bazel_oleksandrmalinin/2c37fc95110689297cb64483825480ed/external/protobuf/0b059a3d8a8f8aa40dde7bea55edca4ec5dfea66.tar.gz: Checksum was e5fdeee6b28cf6c38d61243adff06628baa434a22b5ebb7432d2a7fbabbdb13d but wanted 6d43b9d223ce09e5d4ce8b0060cb8a7513577a35a64c7e3dad10f0703bf3ad93 and referenced by '//tensorflow/python/tools:freeze_graph'.
ERROR: Analysis of target '//tensorflow/python/tools:freeze_graph' failed; build aborted.
INFO: Elapsed time: 14.464s

oleksandrmalinin@oleksandrmalinin:~/serving/tensorflow$ bazel build --config=opt //tensorflow/tools/pip_package:build_pip_package
ERROR: /home/oleksandrmalinin/serving/tensorflow/tensorflow/tools/pip_package/BUILD:100:1: no such package '@protobuf//': java.io.IOException: Error downloading [https://github.com/google/protobuf/archive/0b059a3d8a8f8aa40dde7bea55edca4ec5dfea66.tar.gz, http://mirror.bazel.build/github.com/google/protobuf/archive/0b059a3d8a8f8aa40dde7bea55edca4ec5dfea66.tar.gz] to /home/oleksandrmalinin/.cache/bazel/_bazel_oleksandrmalinin/2c37fc95110689297cb64483825480ed/external/protobuf/0b059a3d8a8f8aa40dde7bea55edca4ec5dfea66.tar.gz: Checksum was e5fdeee6b28cf6c38d61243adff06628baa434a22b5ebb7432d2a7fbabbdb13d but wanted 6d43b9d223ce09e5d4ce8b0060cb8a7513577a35a64c7e3dad10f0703bf3ad93 and referenced by '//tensorflow/tools/pip_package:licenses'.
ERROR: Analysis of target '//tensorflow/tools/pip_package:build_pip_package' failed; build aborted.
INFO: Elapsed time: 1.090s
`