I was trying to build the develop branch to play around with the modified Apple CD code and couldn't get it to build. A quick git bisect and I found that the architecture check in config.h was changed to check for not ARM instead of for x86:

https://github.com/akuker/RASCSI/blob/05db0e46881f6d18a02054f0c3aae8e9abc8bae7/src/raspberrypi/config.h#L23

The check here is incomplete, it should read something like: #if !defined(__arm__) && !defined(__aarch64__) instead to cover 32-bit and 64-bit ARM systems. It may also be good to check that the OS isn't macos too; just in case someone is trying to build on an M1 Mac.