All right, thanks for the tips everyone; currently High Sierra is installed and it can compile for both x86_64 and i386 and both works.
I've installed the cross-compile FPC for PowerPC, but when i try to compile the project, it says:Error: /usr/local/bin/ppcppc can't be executed, error message: Failed to execute "/usr/local/bin/ppcppc", error code: -13
Of course i've tried to run it from terminal and it did work. Both as root and regular user. I also tried to look up the net about what is error code -13, but found nothing.
As for ARM64, it fails with the error messages ofError: clang: error: invalid Darwin version number: macosx11.0.0
Error: clang: error: invalid version number in '--target=arm64-apple-macosx11.0.0'
lazaruspackageintf.pas(104,0) Error: Error while assembling exitcode 1
I thought FreePascal compiles almost API-independent binaries, carrying everything within the binary. Is it possible to compile for a newer OSX, than i have, or i have to make my machine dual booting?