Precise in terms of what? I have no idea why parent brought up implemented in C. It usually is a person who thinks only C is low-level, fast, portable, or whatever enough to handle the task at hand due to shortcoming in other language being discussed. Compiler done in C implies Go wasn't good enough.

Compiler entirely in Go and very fast cancels that whole line of thinking. Far as precision, the original source could've been ported from COBOL and that wouldn't matter. The point would remain it's now in Go and gets the job done.