[yellowapple]

A newer GCC will likely have better optimizations, better safety checks, or what have you that would benefit old codebases using older versions of C's syntax. Similar deal with a newer Clang/LLVM, for that matter.

That is, if we had a GCC version manager that worked the same way things like choosenim or rustup or pyenv or rvm or what have you work, I can guarantee you GCC will ship with an -std flag, because you can bet someone needs to compile a C89 codebase and wants the latest and greatest compiler smarts to do it. Same deal for Clang, or Visual Studio, or `zig cc`, or whatever.

Great example of this (that I just had to deal with this week, lol) is Wine, which mandates C89-compliant code, and yet absolutely benefits from any compiler optimization improvements introduced with newer versions of GCC.