Julian mentioned that it's unsafe to have submodules track from the head of their respective repo because things can break unexpectedly.
I'm thinking a small change we can do is simply fix the submodules to a release commit. Google Test: release 1.8.0 https://github.com/google/googletest/releases/tag/release-1.8.0 Google RE: release 2017-1-1 https://github.com/google/re2/releases/tag/2017-01-01 Google Protobuf2: 2.6.1 https://github.com/google/protobuf/releases/tag/v2.6.1 Zuyu, I know there's some work you did switching to proto3, can you comment on this? Thanks, Marc
