Re: problem importing argp

[Simon Josefsson]

"Gurganus, Brant L" <address@hidden> writes:

> It seems that various AC_FUNC_{} macros in configure.ac modify the behavior of
> the gnulib Makefile on the line containing @LIBOBJS@:
>
> libgnu_a_LIBADD = @LIBOBJS@

Yes, this is a known problem with gnulib.  Gnulib is incompatible with
several AC_FUNC_* functions, and AC_REPLACE_FUNCS in general.

There are some solutions:

1) Use only gnulib modules to replace broken code (in your case, there
   is a memcmp in gnulib too, so import it too, and remove your own
   AC_FUNC_MEMCMP stuff).  If there isn't a replacement module in
   gnulib, consider submitting your function.

2) Create a new configure.ac in a sub-directory of your project that
   is for gnulib only.  This will separate the LIBOBJS in that
   directory from your own.  This has been recommended in the past,
   but it isn't a recommendation that I have followed in my projects
   because it generates much more maintenance, so I understand if you
   don't like this.

3) Fix gnulib to not have this problem.  When this "feature" was
   introduced, I recall that it would be possible to solve this with
   modern versions of autoconf/m4/automake/?.  I'm not sure if this
   actually is the case now.  I agree with Bruno that storing
   information about filenames in M4 macros (which is how the
   AC_LIBOBJ stuff works) is a bad idea.  I don't know how to do this.
   I suspect it should rewrite gnulib's LIBOBJS to use a different
   variable, e.g., gl_LIBOBJS, somehow.

Btw, I sympathise with your problem, but for a different reason: Some
of my projects (LibIDN and GnuTLS) are separated into a LGPL part and
a GPL part.  I can only use the LGPL gnulib modules in those projects,
until this problem is solved.  Further, for GnuTLS, some modules I
want to use in the command-line tools (e.g., xalloc) are things that I
would not want to have linked with the library -- so I want "two"
gnulib directories in one project for this reason too.

/Simon

> Brant Gurganus
> http://www.rose-hulman.edu/~gurganbl
>
> -----Original Message-----
> From: Sergey Poznyakoff [mailto:address@hidden
> Sent: Tue 08/15/06 8:49 AM
> To: Gurganus, Brant L
> Cc: address@hidden
> Subject: RE: problem importing argp
>
> Gurganus, Brant L <address@hidden> wrote:
>
>> Why were those files added to the Makefile when I ran "{path to gnulib
>> checkout}/gnulib-tool --import argp" then and what is the resolution
>> for the problem? They cames from a line that use @ALLOCA@ in the
>> generated Makefile and when I removed AC_FUNC_MEMCMP and friends, the
>> problem went away.
>
> Trying a fresh import I did not experience any of the described
> problems. Notice also that `gnulib-tool --import argp' does not generate
> any `AC_FUNC_MEMCMP' line. Please make sure you use a fresh gnulib
> checkout. 
>
> Regards,
> Sergey