The error first occurs when trying to compile boost's demangle implementation. I saw the error before on a Windows install, could not find a fix, and thus restored the VM to an earlier state. That worked for a while but after a series of recent windows upgrades the error started occurring again. Removing all of CMake's build artifacts and "starting again" with CMake configuring and building does not fix the issue. I am going to try to re-install VS Community.