In documentation page
https://www.freepascal.org/docs-html/prog/progap7.html , table G.2 (CPU-related defines), the important define CPUAARCH64 seems to be missing. I discovered it by trial and error, when compiling with FPC 3.2.2 for macOS on Apple Silicon / aarch64, while looking for an M1 correspondent of Intel's CPUX86_64.