I've started looking into making C++ .dll plugins for New Vegas, which is done through the New Vegas Script Extender libraries. Installed VS 2019, opening the solution for the example plugin source code, and compiling throws a huge number of errors when the libraries are compiled, for both the headers and the .cpp files.
Why is that? Surely it should just work after the project is upgraded to the latest Visual Studio, but apparently not.
Source code: http://nvse.silverlock.org/download/nvse_5_1_beta4.7z
Error log: https://pastebin.com/raw/xgJUAPjP