To anyone implementing the automatic dependency generation mentioned in this article, you can actually make things even simpler by combining the compiling and dependency steps.

This works because if you add a new dependency to a file, that information will only be needed for the next build - the current file will already be considered out of date seeing as it was edited to add the #include.

  gcc -MD -MP foo.c -o foo.o

Will compile foo.c into foo.o, and also generate foo.d (-MD). Foo.d will contains make style dependencies, and also a phony target for every dependency (-MP). This allows you to delete dependant files, as make considers the target of a rule that has no perquisites or commands to be up to date if said target does not exist.