Re: call AC_DISABLE_SHARED "conditionally" for a certain host

[Ralf Wildenhues]

[ removing the autoconf list ]

> * Florian Schricker wrote on Tue, Feb 14, 2006 at 11:03:50AM CET:
> > 
> >     AC_CANONICAL_HOST
> >     case "$host" in
> >       *-*-linux* | *-*-darwin*)
> >         ;;
> >       *-*-mingw32*)
> >         AC_DISABLE_SHARED
> >         ;;
> >     esac
> > 
> > But I guess I am missing something; it does not work. Running this
> > configure on GNU/Linux gives:
> > 
> >     checking whether to build shared libraries...
> >     checking whether to build static libraries... yes
> 
> Confirmed with both branch-1-5 and HEAD.

> I'm inclined to "fix" this by adjusting the documentation, not the
> implementation of these macros.

Hrmpf.  CVS HEAD Libtool's new interface actually leaves less
flexibility for the user there.

This will not work:

  case $host in
  foo) set_shared=disable-shared ;;
  *)   set_shared= ;;
  esac
  LT_INIT([$set_shared])

because the arguments to LT_INIT are interpreted at m4 time already.
And this
  case $host in
  foo) LT_INIT([disable-shared]) ;;
  *)   LT_INIT ;;
  esac

will cause *major* breakage (thanks to AC_REQUIRE).  :-/

Even this, broken as it is for other reasons:
  AS_IF([test "$host_os" = linux-gnu],
        [LT_INIT],
        [AS_IF([test "$host_os" = mingw32]
               [LT_INIT([disable-shared])])])

will not work: we make sure LT_INIT is expanded only once.

Luckily we do have full backward compatible support for
AC_DISABLE_SHARED and related macros, including their respective bugs.
I'm just wondering whether we should reconsider obsoleting it: I regard
the aforementioned use as quite suitable.

Another lesson learned: There should be an AS_CASE.

Cheers,
Ralf