Re: make: compilation firewall

On Feb 16, 12:45 pm, [email protected] (Paul Jarc) wrote:
> "Michael" <[email protected]> wrote:
> > out.h out.cc: in.our_format generate
> >      generate -i in.our_format -o tmp
> >      if (tmp.h != out.h OR tmp.cc != out.cc) {
> >          cp tmp.h out.h
> >          cp tmp.cc out.cc
> >      }
>
>         if { cmp tmp.h out.h && cmp tmp.cc out.cc; } > /dev/null 2>&1; \
>           then :; \
>           else cp tmp.h out.h && cp tmp.cc out.cc; \
>         fi
>
> You could also incorporate this conditional update into generate
> itself, to keep the Makefile simpler.
>
> paul

I actually tried something like this, but it recompiled everything
whenever generate changed (i.e., whenever the rule for out.h and
out.cc fired), not just when out.h and out.cc actually changed.  I
think I'm missing something to get the dependencies right.

Michael