Re: Cached exeext values with Libtool 1.4 and autoconf 2.50

[Alexandre Oliva]

On Jun 21, 2001, Matthias Koeppe <address@hidden> wrote:

> When trying to build CVS Guile with Libtool 1.4, autoconf 2.50 and CVS
> automake on Solaris, I noticed that libtool and autoconf seem to
> disagree about the meaning of the ac_exeext variable.

Indeed.  The worst thing is that it appears that autoconf has indeed
changed the no-exeext value, so config.caches can no longer be shared
between configure scripts built using autoconf 2.13 and those built
with autoconf 2.50.  I suppose autoconf should have renamed the cache
variable when its contents changed.

Anyway, the inconsistency between autoconf and libtool is already
fixed in CVS libtool: the ltconfig code has all been folded into
libtool.m4, and AC_EXEEXT is used from whatever autoconf version the
developer chooses.

But the problem of cache-coherence between different versions of
autoconf remains.  Akim, Lars?

>  * Older autoconfs seem to set ac_exeext=no to indicate that no exe
>    extension is in use; autoconf 2.50 seems to make ac_exeext empty. 

>  * From autoconf ChangeLog:

>     | 2001-01-22  Lars J. Aas  <address@hidden>
>     | 
>     |         * aclang.m4 (_AC_COMPILER_EXEEXT_DEFAULT, 
> _AC_COMPILER_EXEEXT_O):
>     |         Export ac_cv_exeext so ltconfig believes the value is cached and
>     |         skips its own faulty test.

>  * From libtool ChangeLog:

>     | 1999-06-09  Gary V. Vaughan  <address@hidden>
>     | 
>     |         * ltconfig.in (exeext): autoconf's AC_EXEEXT uses "no" to 
> indicate
>     |         no extension, and we must do the same in order to share the 
> cache
>     |         value. Also we must ignore conftest.err which HPsUX (at least)
>     |         fills with gratuitous warnings.

>  * An ac_exeext value of "no" seems to creep into the cache file
>    during the configuration of the convenience ltdl copy in Guile.  I
>    built libtool with autoconf 2.50 and libtoolized Guile with this
>    build, so I think the ltdl copy is up-to-date w.r.t. the autoconf
>    version. 

> Does this make sense to anyone?

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  address@hidden, redhat.com}
CS PhD student at IC-Unicamp        address@hidden, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me