The linker de-duping identical machine code is common, but most frontends that do monomorphization aren't that smart about identical copies, because monomorphiz

The linker de-duping identical machine code is common, but most frontends that do monomorphization aren't that smart about identical copies, because monomorphization is usually done with source-level types, and there are lots of typeful operations that need to get resolved and lowered before it's known that the machine code will be identical.