argp: no --version

[Andrew Schulman]

gnulib newbie here.  Great collection, y'all.

I'm trying to build argp from gnulib as a shared library, libargp, for
Cygwin. It works, except for one thing:  the programs that link against it
don't offer a --version option, which argp is supposed to provide
automatically.  Can someone please tell me what I'm doing wrong?

I extract the source from current gnulib with

gnulib-tool --create-testdir --lib=libargp --libtool \
  argp argp-version-etc version-etc-fsf

then adjust gllib/Makefile.am slightly to build a shared library.  I build
it and get

  /usr/bin/cygargp-0.dll
  /usr/include/argp.h
  /usr/lib/libargp.dll.a
  /usr/lib/libargp.la

So far, so good.  But now when I build, for example, Argp example #2
against it, it works but there's no --version option:

$ ./argpex2 --help
Usage: argpex2 [OPTION...]
Argp example #2 -- a pretty minimal program using argp

  -?, --help                 give this help list
      --usage                give a short usage message

$ ./argpex2 --version
./argpex2: unrecognized option '--version'
Try `argpex2 --help' or `argpex2 --usage' for more information.

Any help appreciated.
Andrew.