Providing library functions as part of autoconfiscation

[Paolo Bonzini]

Akim suggested recently on bison-patches that autoconf include several
possible replacement functions and that as part of autoconfiscating a
package the files would be added to it (another part of the suggestion was
to have the program specify its license and only include files that were
compatible with that license).

There are three possible places to do so: the first is autoreconf, the
second is automake, the third is a new program (I'll call it autolib).
Each one would have pros and cons:

1) The feature might be useful to programs not using Automake.
OTOH autoreconf is currently only a driver for other autotools.

2) IIRC, Automake is already tracking AC_LIBSOURCE so it should be the
easiest place to add the new feature.  OTOH the feature might be useful to
programs not using Automake.  This is the one I like the least.

3) It is the biggest task to write Autolib, and also the slowest since it
means invocating Autom4te once more.  OTOH I think this is the cleanest
solution (and besides, one would probably want to invoke Autolib every now
and then, for example when he added a new AC_REPLACE_FUNCS call).  It
comes to mind that Autolib could also add COPYING or COPYING.LIB files to
the project.

Given the amount of reinventing the wheel when dealing with replaced
functions and the (small but consistently present, and boring) work to do
to add standard files like getopt* when creating a new package, I think
that this would be a really good thing.  Any comments (as well as better
names for autolib)?

Paolo