Automatic dependency tracking

[Tom Tromey]

>>>>> "Tom" == Tom Tromey <tromey@redhat.com> writes:

Tom> FWIW, rewriting the patch I sent to avoid GNU make is likely to
Tom> be pretty fiddly & painful.

So much for guessing.  Now I think it isn't too bad, if we do not mind
having dependencies only in the GNU make case.

Daniel> So timestamps shouldn't matter; the only new failure mode is
Daniel> that if you modify a header, the source files including it
Daniel> might not be automatically rebuilt.

I am happy to implement this, but it will be a major regression for
folks not using GNU make.

Tom