When I finally left XP I didn't have to declare extra variables (that get optimized out but still HAD to be declared to compile) any more.
My Arduino computer is now a Raspberry Pi 3+ running Raspbian (Debian Linux based) without a hitch. Compile speed beats XP on a 32-bit Sempron-CPU PC running almost 3x as fast and with twice the RAM as the RPi has.
An RPi 3+ board runs $40 and a 3A 5V PS runs $15. It needs a video cable, USB KB & mouse and SD card to run. USB drives whether stick or external HD work for storage. It uses almost no power compared to a PC, only heavy graphics pushed mine to need more than 2A which is when I bought a 3A supply.
The new RPi 4 is a hog compared, it needs a fan.