Bug#143590: autoconf 2.53 causes ncpfs to not build from source

[Ben Pfaff]

Hi.  I'm the maintainer of the Debian GNU/Linux package for
Autoconf.  The following bug report was recently filed.  I don't
think it's a bug that I introduced, and it isn't obvious to me
that it's a bug in the submitter's configure.in, so I thought I'd
forward it upstream.

Thanks,

Ben.

-------------------- Start of forwarded message --------------------
Subject: Bug#143590: autoconf 2.53 causes ncpfs to not build from source
Reply-To: Petr Vandrovec <[EMAIL PROTECTED]>, [EMAIL PROTECTED]
Received: via spool by [EMAIL PROTECTED] id=B.101922602923857
          (code B ref -1); Fri, 19 Apr 2002 14:33:01 GMT
Date: Fri, 19 Apr 2002 16:20:26 +0200
From: Petr Vandrovec <[EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
Cc: [EMAIL PROTECTED]
Message-ID: <[EMAIL PROTECTED]>
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User-Agent: Mutt/1.3.28i
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Lines: 43
Xref: pfaff.Stanford.EDU other:36742

Package: autoconf
Version: 2.53-2

Hi,
  for years I'm using nested AC_CHECK_HEADER directives in
the ncpfs package. And today I decided to rebuild configure script
and I found that for input below it generates broken output -
output will contain

# So?  What about this header?
case $ac_header_compiler:$ac_header_preproc in
  yes:no
fi

which cannot be parsed by shell (there is missing brace, and fi
should be about 50 lines down in the output). Non-nested AC_CHECK_HEADER 
works ok, but I have no idea how I could rewrite code below without
nesting AC_CHECK_HEADER while still maintaining code readability.
It worked with autoconf 2.52.

dnl stripped down configure.ac from ncpfs
dnl Process this file with autoconf to produce a configure script.
AC_PREREQ(2.50)
AC_INIT([[ncpfs]],[[2.2.0.19.1]],[[[EMAIL PROTECTED]]])
AC_REVISION([[2.2.0.19.1]])

AC_PROG_CC
AC_CHECK_HEADER(net/if.h,
  [ncp_net_if_h="#include <net/if.h>"],
  AC_CHECK_HEADER(linux/if.h,
    [ncp_net_if_h="#include <linux/if.h>"],
    [ncp_net_if_h="/* No interfaces support... */"
     AC_DEFINE(NO_NET_IF_SUPPORT, 1, [neither net/if.h nor linux/if.h was found, so 
ipx_* will not build...])
     AC_MSG_WARN(Neither <net/if.h> nor <linux/if.h> does exist, only partial make 
configured)]
  )
)

                                        Thanks,
                                                Petr Vandrovec
                                                ncpfs upstream maintainer

-------------------- End of forwarded message --------------------

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