Re: dependencies with @xx@ variables

[Ralf Wildenhues]

* Joakim Tjernlund wrote on Wed, Jan 27, 2010 at 09:08:16AM CET:
> Ralf Wildenhues wrote on 2010/01/27 08:08:09:
> >
> > No.  When automake cannot see a literal in a *_LDADD or *_LIBADD
> > statement, it cannot interpolate it to the respective *_DEPENDENCIES
> > variable: non-literal content might expand to stuff like '-lm' or
> > '-L/foo' which would cause 'make' to barf if listed as prerequisites
> > somewhere.
> 
> I see, I tried setting *_DEPENDENCIES to *_LDADD and that worked
> even though *_LDADD contains -lm and as I read your stmt above it
> should barf on -lm. Can GNU make handle this?

Seems like it.  It's not portable to other makes though.

> > > How do I workaround it?
> >
> > Build the *_DEPENDENCIES variable yourself.  You have to take care of
> > all of its entries if you do so, it overwrites, not appends to, any
> > automake-computed library dependencies.
> 
> Would it be terribly bad if I did:
>  *_DEPENDENCIES = $(am__DEPENDENCIES_1) $(address@hidden@)
> That way I hope to append the needed deps. Will it break in
> mysterious ways?

Yes.  It will break as soon as your Makefile.am changes sufficiently for
automake to decide that $(am__DEPENDENCIES_2) will be the needed helper
variable (which can be with just another library created), or the next
version of Automake decides to use a different internal name altogether.
IOW, don't rely on such a hack.

Cheers,
Ralf