Thank you!

It's similar with Turbo Pascal 3.0, but there's only one segment since it's a good old COM file. The compiler just copies its own first ~10000 bytes, comprising the standard library, and splices the compiled result to the end.

I can see how this makes transcompilation relatively straightforward, although the real mode 16-bit code is a bit unpleasant with all the segment stuff going on, so you might as well just decompile :D. It's very possible that similar instructions will be emitted in 3.0 and 4.0 for the same source input.

My program also has the stack checking calls everywhere before calling functions. I think that people using Pascal weren't worried about performance that much to begin with, so they didn't bother disabling it.