Hi! First of all, this is an excellent post. There is a lot of really great information about make here!
I could be wrong, but I may have identified an error or inconsistency. In discussing file dependencies, DEPFLAGS and DEP_FILES are defined one way in the first example and another way in the Git repo and in the full example. I tried both, and although they generated dependency files, they didn’t seem to work. By that I mean, when I modified the source files to include a “magic number” from “example.h”, changing the magic number didn’t cause a rebuild of the executable. I’d be happy to provide source code, if needed.
Thanks for doing the Interrupt blog! This is one of the best sources of information for embedded systems that I’ve yet found!!