Issue with devtools

[stheroux]

From Marco: I was running R 3.4.1 but updated to R 3.5.1 because the ASCI calculator says I need R 3.5.0 or later. My problem, though, is I cannot install 'devtools'. I have spent hours searching the internet to try to solve my problem and Heili was unable to help. Have you had any issues updating? Some of the packages (e.g., processx, callr, cachem, memoise) have a binary version earlier than the source version, and the ASCI package requires the later source version but my system will not update accordingly. I am including some screen shots so you can see some of the errors. If I cannot figure this out, I cannot calculate ASCI for Andy. Any help would be much appreciated.