can I suppress "invalid unused variable name"?

[Steve M. Robbins]

Hi,

I am working with a library (CGAL) that is not autoconfigured, but has
its own system that generates a makefile fragment with important make
variables defined.  In particular, it defines CGAL_LDFLAGS.

In my Makefile.am, I use

        include $(CGAL_MAKEFILE)
        ...
        LDADD = ... $(CGAL_LDFLAGS) ...

and automake complains:

        Makefile.am: invalid unused variable name: `CGAL_LDFLAGS'

[Incidentally, there used to be a line number attached to this diagnostic,
but that suddenly stopped. (??)]

Since automake does generate the correct output Makefile.in, I can
live with seeing this message all the time.  However, I am concerned
that this "warning" may change to an error in the future, and my
builds will suddenly break.  Thus I wonder: what is the automake-blessed
way to deal with including makefile fragments that define variables
that automake considers its own?

I used to be able to suppress this behaviour by a dummy assign to 
CGAL_LDFLAGS (before including CGAL_MAKEFILE, of course!).  But that
trick has stopped working.

Thanks,
-Steve


-- 
by Rocket to the Moon,
by Airplane to the Rocket,
by Taxi to the Airport,
by Frontdoor to the Taxi,
by throwing back the blanket and laying down the legs ...
- They Might Be Giants