In case of interest for those unfortunate who need to evaluate if manually porting ROOT5 to VC2015 might actually be worth doing despite of all the good reasons not to, it seems that it’s relatively easy to get at least basic parts of ROOT to compile as demonstrated here (note that while the diff seems rather long, most of it comes from unmodified copy-paste content): with those changes default CMake config excluding ‘cintex’ and ‘reflex’ builds on VC2015, but worth stressing is that no runtime tests of anykind have been done and this is simply a demonstration. Changes in non-CINT code are fairly trivial and not expected to cause problems, but CINT-related modifications are much more dubious.