You could write something along the lines of `writeln` using `array of const` with today's Free Pascal. It's still strictly better that it's actually implemented as a built-in for various reasons, though.

Also, yes, Free Pascal is entirely self-hosted from the bottom up, making use of inline assembly blocks in some places where it's necessary. It is to Pascal what GCC is to C and C++, basically (which is to say, it has no real dependencies on toolchains other than itself).