For those who are interested in developing a realistically useful small OS in C++ (or even C++ 11), you may probably want to check out OSv https://github.com/cl

For those who are interested in developing a realistically useful small OS in C++ (or even C++ 11), you may probably want to check out OSv https://github.com/cloudius-systems/osv/ https://github.com/cloudius-systems/osv/ developed by previous KVM guys.