Can't build Boost::atomic

I've extracted a number of Boost's sub projects as source into my project using bcp.

I've set CMake to find the Boost library under my project and not the one installed on my system: https://gist.github.com/ruipacheco/bae9f6694f5760da90b2

I'm now trying to build my project but Boost::atomic fails while trying to find a file that indeed has not been extracted: https://gist.github.com/ruipacheco/954d0cf0dbb8ece7db75

Is there a pre-processing step I missed with Boost when extracting the libraries? Why is it referencing a file that doesn't exist?