Dmitry> i am not looking forward to -include (even though -include is Dmitry> supported by bmake, gnu make and sun make). Dmitry> -include robs the user the error message should make fails to rebuild a depfile. Dmitry> i'd rather introduce rules to rebuild depfiles, as presented in the Dmitry> earlier email.
It's been a long time since I worked on automake, but the dependency tracking in automake is designed not to need to rebuild or pre-build dep files. Doing that means invoking the compiler twice, which is slow. Instead, automake computes dependencies as a side effect of compilation. What is the scenario where you both end up with an empty depfile and a compilation that isn't out of date for some other reason? That seems like it shouldn't be possible. Tom