Travis on Ubuntu 14.04 is consistently failing with:
/home/travis/build/mongodb/mongo-cxx-driver/src/bsoncxx/test/bson_value.cpp:49:30: error: no matching constructor for initialization of 'bson_value::view' bson_value::view view{value};
https://travis-ci.org/github/mongodb/mongo-cxx-driver/jobs/694740305