Re: ideas on multiple LIBOBJS support

[Ralf Wildenhues]

Hello Paul, Eric,

* Paul Eggert wrote on Thu, Aug 31, 2006 at 06:48:37PM CEST:
> One quick reaction is that this:
> 
> > # If VARNAME is omitted, default to the VARNAME set by the most recent
> > # AC_CONFIG_LIBOBJ_DIR (or LIBOBJS if no dir has been specified).
> 
> won't work well in the presence of AC_REQUIRE, since the "most recent"
> is relative.  Why not have VARNAME default to LIBOBJS instead?

Because that will not allow you to "divert" stuff that comes from
any third-party macros, e.g., an Autoconf macro.

Eric's idea could "work" even in the presence of AC_REQUIRE, but it may
not do what the user thinks it would do, so it is at least fragile.

If you can assume that each libobj has a unique basename, you could use
that to key off the directory; maybe with some wildcard mechanism, the
default being that all end up in $ac_config_libobj_dir.  If you have
several keys, you just expand the matching libobjs in the makefiles
where they are needed.

Please also note that Automake may need special magic for expanding the
names of the objects/sources in different directories: to some `make'
implementations, `./foo.o' is not the same as `foo.o', and you need to
use the same representation that is used elsewhere (this is important
for subdir-objects, for example).

IIRC, some of the above thoughts were from a discussion with Stepan and
Gary about this a while ago; and there must be some more in the
archives, but I can't find it right now.  In any case, I fear the
Automake part will be more trouble than the Autoconf part...

Cheers,
Ralf