[m463]

This is one of those things that is hard to do, but great to have done. It's hard to do with a codebase in flight with lots of people working on it.

What I remember implementing this on projects was the messiness of:

- incrementally getting the Makefiles to turn on -Wall file-by-file as they were scrubbed. I think it was something similar to "<list-of-files>: CFLAGS+=-Wall" and then add to the list.

- suppressing warnings that were "ok" on a case-by-case basis. different languages had different ways of saying "ignore error 123 here" if at all.

- I remember lint had things like this too, like /NOTREACHED/

maybe things have gotten better/cleaner.