Handling Long Branches

It looks like the author has renamed their blog post, and thus the link has changed: https://maskray.me/blog/2026-01-25-long-branches-in-compiler...

This is really useful! I only knew about -mcmodel during compilation but I didn’t know the linker would insert thunks for faraway branches. I would’ve thought that the linker would simply complain and ask you to recompile with a larger code model. Also interesting that different linkers (or the same linker on different architectures!) chose different thunk creation algorithms.

It was only a couple of years ago since I wrote an assembly language program of my own and got hit by branching-limits on the Z80 processor.

I did exactly the same things that were suggested in this article, either inverted conditionals, or had a thunk - essentially "jmp nextJump", where that jumped to the actual location.

I sometimes spent a few hours shuffling code around to remove the longer jumps and re-order code in groups closer together to save individual bytes.