Question

In the event that a Makefile itself is changed, a safe bet would be to consider all targets out of date.

Is there a clever way to add this dependency? Are there any alternatives?

Answer 1

A safe bet, but a terrible idea. Example: you’re using automake and update Makefile.am to add a single source file. The correct response is to compile just the new file and link it in. In your scheme everything would be rebuilt.

Moreover, adding the dependency isn’t going to do anything unless you touch the file, something like:

$(SRCS): Makefile
    touch $@

This will then trip up editors that use the mtime to detect concurrent modification (emacs is one example).

If you’re doing something major, just run make clean all after doing the change.