Thread: Fix autoconf deprecation warnings

Hi,

When working with the autoconf rule for detecting __int128 I noticed we
get a lot of warnings like the below in the autconf trace output so I
decided to clean them up. All the macros we get complaints about seems
to have been made obsolete between 2000 and 2003, and since we have a
generated configure in the repository I personally think it is
reasonable to drop support for such ancient versions of autoconf.

m4trace:configure.in:376: -1- _m4_warn([obsolete], [The macro
`AC_TRY_COMPILE' is obsolete.

The patch is split into four parts since there are several different
obsolete macros (AC_TRY_*, AC_LANG_SAVE/AC_LANG_RESTORE,
AC_DECL_SYS_SIGLIST) which I replace. Feel free to squash the patches
into one if you wish.

The second patch in the series removes a handful of empty main functions
from configure. As far as I can tell these cannot have any use, and with
the use of the AC_LANG_* macros they were easy to remove.

--
Andreas Karlsson

I have attached new versions which apply on the current master.

Andreas

On 05/31/2015 05:22 AM, Andreas Karlsson wrote:
> I have attached new versions which apply on the current master.

Thanks, applied.

> --- a/configure.in
> +++ b/configure.in
> @@ -1473,7 +1473,7 @@ if test x"$pgac_cv_func_sigsetjmp" = x"yes"; then
>    AC_DEFINE(HAVE_SIGSETJMP, 1, [Define to 1 if you have sigsetjmp().])
>  fi
>
> -AC_DECL_SYS_SIGLIST
> +AC_CHECK_DECLS([sys_siglist])
>
>  AC_CHECK_FUNC(syslog,
>                [AC_CHECK_HEADER(syslog.h,

Hmm, according to the autoconf manual:

> Macro: AC_DECL_SYS_SIGLIST
>
>     Same as:
>
>               AC_CHECK_DECLS([sys_siglist], [], [],
>               [#include <signal.h>
>               /* NetBSD declares sys_siglist in unistd.h.  */
>               #ifdef HAVE_UNISTD_H
>               # include <unistd.h>
>               #endif
>               ])
>
>     See AC_CHECK_DECLS.

So I replaced AC_DECL_SYS_SIGLIST with that full snippet instead.

- Heikki