Import AM_ICONV implementation

We *have* to have config.rpath in our own directory, for reasons which
escape me. Usually it would be installed by gettextize or gnulib-tool
but we're not *using* either of those, so just pull in the AM_ICONV bits
manually.

We don't want to ship just config.rpath and *not* the M4 files because
that way we might end up with mismatching versions.

I hate autohell.

(Files taken from Fedora gettext 0.19.2-5.fc21)
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Makefile.am

@@ -221,3 +221,5 @@ po/$(PACKAGE).pot: $(POTFILES) version.sh
 	  --package-name="@PACKAGE@" --package-version="@VERSION@" \
 	  --msgid-bugs-address=openconnect-devel@lists.infradead.org \
 	  -o $@ $(POTFILES)
+
+ACLOCAL_AMFLAGS = -I m4

autogen.sh

 #!/bin/sh
 
-aclocal && \
+aclocal -I m4 && \
 ${LIBTOOLIZE:-libtoolize} --automake --force && \
 autoheader --force &&
 automake --foreign --add-missing --force && \

m4/iconv.m4

+# iconv.m4 serial 18 (gettext-0.18.2)
+dnl Copyright (C) 2000-2002, 2007-2014 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Bruno Haible.
+
+AC_DEFUN([AM_ICONV_LINKFLAGS_BODY],
+[
+  dnl Prerequisites of AC_LIB_LINKFLAGS_BODY.
+  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+  AC_REQUIRE([AC_LIB_RPATH])
+
+  dnl Search for libiconv and define LIBICONV, LTLIBICONV and INCICONV
+  dnl accordingly.
+  AC_LIB_LINKFLAGS_BODY([iconv])
+])
+
+AC_DEFUN([AM_ICONV_LINK],
+[
+  dnl Some systems have iconv in libc, some have it in libiconv (OSF/1 and
+  dnl those with the standalone portable GNU libiconv installed).
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+  dnl Search for libiconv and define LIBICONV, LTLIBICONV and INCICONV
+  dnl accordingly.
+  AC_REQUIRE([AM_ICONV_LINKFLAGS_BODY])
+
+  dnl Add $INCICONV to CPPFLAGS before performing the following checks,
+  dnl because if the user has installed libiconv and not disabled its use
+  dnl via --without-libiconv-prefix, he wants to use it. The first
+  dnl AC_LINK_IFELSE will then fail, the second AC_LINK_IFELSE will succeed.
+  am_save_CPPFLAGS="$CPPFLAGS"
+  AC_LIB_APPENDTOVAR([CPPFLAGS], [$INCICONV])
+
+  AC_CACHE_CHECK([for iconv], [am_cv_func_iconv], [
+    am_cv_func_iconv="no, consider installing GNU libiconv"
+    am_cv_lib_iconv=no
+    AC_LINK_IFELSE(
+      [AC_LANG_PROGRAM(
+         [[
+#include <stdlib.h>
+#include <iconv.h>
+         ]],
+         [[iconv_t cd = iconv_open("","");
+           iconv(cd,NULL,NULL,NULL,NULL);
+           iconv_close(cd);]])],
+      [am_cv_func_iconv=yes])
+    if test "$am_cv_func_iconv" != yes; then
+      am_save_LIBS="$LIBS"
+      LIBS="$LIBS $LIBICONV"
+      AC_LINK_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[
+#include <stdlib.h>
+#include <iconv.h>
+           ]],
+           [[iconv_t cd = iconv_open("","");
+             iconv(cd,NULL,NULL,NULL,NULL);
+             iconv_close(cd);]])],
+        [am_cv_lib_iconv=yes]
+        [am_cv_func_iconv=yes])
+      LIBS="$am_save_LIBS"
+    fi
+  ])
+  if test "$am_cv_func_iconv" = yes; then
+    AC_CACHE_CHECK([for working iconv], [am_cv_func_iconv_works], [
+      dnl This tests against bugs in AIX 5.1, AIX 6.1..7.1, HP-UX 11.11,
+      dnl Solaris 10.
+      am_save_LIBS="$LIBS"
+      if test $am_cv_lib_iconv = yes; then
+        LIBS="$LIBS $LIBICONV"
+      fi
+      AC_RUN_IFELSE(
+        [AC_LANG_SOURCE([[
+#include <iconv.h>
+#include <string.h>
+int main ()
+{
+  int result = 0;
+  /* Test against AIX 5.1 bug: Failures are not distinguishable from successful
+     returns.  */
+  {
+    iconv_t cd_utf8_to_88591 = iconv_open ("ISO8859-1", "UTF-8");
+    if (cd_utf8_to_88591 != (iconv_t)(-1))
+      {
+        static const char input[] = "\342\202\254"; /* EURO SIGN */
+        char buf[10];
+        const char *inptr = input;
+        size_t inbytesleft = strlen (input);
+        char *outptr = buf;
+        size_t outbytesleft = sizeof (buf);
+        size_t res = iconv (cd_utf8_to_88591,
+                            (char **) &inptr, &inbytesleft,
+                            &outptr, &outbytesleft);
+        if (res == 0)
+          result |= 1;
+        iconv_close (cd_utf8_to_88591);
+      }
+  }
+  /* Test against Solaris 10 bug: Failures are not distinguishable from
+     successful returns.  */
+  {
+    iconv_t cd_ascii_to_88591 = iconv_open ("ISO8859-1", "646");
+    if (cd_ascii_to_88591 != (iconv_t)(-1))
+      {
+        static const char input[] = "\263";
+        char buf[10];
+        const char *inptr = input;
+        size_t inbytesleft = strlen (input);
+        char *outptr = buf;
+        size_t outbytesleft = sizeof (buf);
+        size_t res = iconv (cd_ascii_to_88591,
+                            (char **) &inptr, &inbytesleft,
+                            &outptr, &outbytesleft);
+        if (res == 0)
+          result |= 2;
+        iconv_close (cd_ascii_to_88591);
+      }
+  }
+  /* Test against AIX 6.1..7.1 bug: Buffer overrun.  */
+  {
+    iconv_t cd_88591_to_utf8 = iconv_open ("UTF-8", "ISO-8859-1");
+    if (cd_88591_to_utf8 != (iconv_t)(-1))
+      {
+        static const char input[] = "\304";
+        static char buf[2] = { (char)0xDE, (char)0xAD };
+        const char *inptr = input;
+        size_t inbytesleft = 1;
+        char *outptr = buf;
+        size_t outbytesleft = 1;
+        size_t res = iconv (cd_88591_to_utf8,
+                            (char **) &inptr, &inbytesleft,
+                            &outptr, &outbytesleft);
+        if (res != (size_t)(-1) || outptr - buf > 1 || buf[1] != (char)0xAD)
+          result |= 4;
+        iconv_close (cd_88591_to_utf8);
+      }
+  }
+#if 0 /* This bug could be worked around by the caller.  */
+  /* Test against HP-UX 11.11 bug: Positive return value instead of 0.  */
+  {
+    iconv_t cd_88591_to_utf8 = iconv_open ("utf8", "iso88591");
+    if (cd_88591_to_utf8 != (iconv_t)(-1))
+      {
+        static const char input[] = "\304rger mit b\366sen B\374bchen ohne Augenma\337";
+        char buf[50];
+        const char *inptr = input;
+        size_t inbytesleft = strlen (input);
+        char *outptr = buf;
+        size_t outbytesleft = sizeof (buf);
+        size_t res = iconv (cd_88591_to_utf8,
+                            (char **) &inptr, &inbytesleft,
+                            &outptr, &outbytesleft);
+        if ((int)res > 0)
+          result |= 8;
+        iconv_close (cd_88591_to_utf8);
+      }
+  }
+#endif
+  /* Test against HP-UX 11.11 bug: No converter from EUC-JP to UTF-8 is
+     provided.  */
+  if (/* Try standardized names.  */
+      iconv_open ("UTF-8", "EUC-JP") == (iconv_t)(-1)
+      /* Try IRIX, OSF/1 names.  */
+      && iconv_open ("UTF-8", "eucJP") == (iconv_t)(-1)
+      /* Try AIX names.  */
+      && iconv_open ("UTF-8", "IBM-eucJP") == (iconv_t)(-1)
+      /* Try HP-UX names.  */
+      && iconv_open ("utf8", "eucJP") == (iconv_t)(-1))
+    result |= 16;
+  return result;
+}]])],
+        [am_cv_func_iconv_works=yes],
+        [am_cv_func_iconv_works=no],
+        [
+changequote(,)dnl
+         case "$host_os" in
+           aix* | hpux*) am_cv_func_iconv_works="guessing no" ;;
+           *)            am_cv_func_iconv_works="guessing yes" ;;
+         esac
+changequote([,])dnl
+        ])
+      LIBS="$am_save_LIBS"
+    ])
+    case "$am_cv_func_iconv_works" in
+      *no) am_func_iconv=no am_cv_lib_iconv=no ;;
+      *)   am_func_iconv=yes ;;
+    esac
+  else
+    am_func_iconv=no am_cv_lib_iconv=no
+  fi
+  if test "$am_func_iconv" = yes; then
+    AC_DEFINE([HAVE_ICONV], [1],
+      [Define if you have the iconv() function and it works.])
+  fi
+  if test "$am_cv_lib_iconv" = yes; then
+    AC_MSG_CHECKING([how to link with libiconv])
+    AC_MSG_RESULT([$LIBICONV])
+  else
+    dnl If $LIBICONV didn't lead to a usable library, we don't need $INCICONV
+    dnl either.
+    CPPFLAGS="$am_save_CPPFLAGS"
+    LIBICONV=
+    LTLIBICONV=
+  fi
+  AC_SUBST([LIBICONV])
+  AC_SUBST([LTLIBICONV])
+])
+
+dnl Define AM_ICONV using AC_DEFUN_ONCE for Autoconf >= 2.64, in order to
+dnl avoid warnings like
+dnl "warning: AC_REQUIRE: `AM_ICONV' was expanded before it was required".
+dnl This is tricky because of the way 'aclocal' is implemented:
+dnl - It requires defining an auxiliary macro whose name ends in AC_DEFUN.
+dnl   Otherwise aclocal's initial scan pass would miss the macro definition.
+dnl - It requires a line break inside the AC_DEFUN_ONCE and AC_DEFUN expansions.
+dnl   Otherwise aclocal would emit many "Use of uninitialized value $1"
+dnl   warnings.
+m4_define([gl_iconv_AC_DEFUN],
+  m4_version_prereq([2.64],
+    [[AC_DEFUN_ONCE(
+        [$1], [$2])]],
+    [m4_ifdef([gl_00GNULIB],
+       [[AC_DEFUN_ONCE(
+           [$1], [$2])]],
+       [[AC_DEFUN(
+           [$1], [$2])]])]))
+gl_iconv_AC_DEFUN([AM_ICONV],
+[
+  AM_ICONV_LINK
+  if test "$am_cv_func_iconv" = yes; then
+    AC_MSG_CHECKING([for iconv declaration])
+    AC_CACHE_VAL([am_cv_proto_iconv], [
+      AC_COMPILE_IFELSE(
+        [AC_LANG_PROGRAM(
+           [[
+#include <stdlib.h>
+#include <iconv.h>
+extern
+#ifdef __cplusplus
+"C"
+#endif
+#if defined(__STDC__) || defined(_MSC_VER) || defined(__cplusplus)
+size_t iconv (iconv_t cd, char * *inbuf, size_t *inbytesleft, char * *outbuf, size_t *outbytesleft);
+#else
+size_t iconv();
+#endif
+           ]],
+           [[]])],
+        [am_cv_proto_iconv_arg1=""],
+        [am_cv_proto_iconv_arg1="const"])
+      am_cv_proto_iconv="extern size_t iconv (iconv_t cd, $am_cv_proto_iconv_arg1 char * *inbuf, size_t *inbytesleft, char * *outbuf, size_t *outbytesleft);"])
+    am_cv_proto_iconv=`echo "[$]am_cv_proto_iconv" | tr -s ' ' | sed -e 's/( /(/'`
+    AC_MSG_RESULT([
+         $am_cv_proto_iconv])
+    AC_DEFINE_UNQUOTED([ICONV_CONST], [$am_cv_proto_iconv_arg1],
+      [Define as const if the declaration of iconv() needs const.])
+    dnl Also substitute ICONV_CONST in the gnulib generated <iconv.h>.
+    m4_ifdef([gl_ICONV_H_DEFAULTS],
+      [AC_REQUIRE([gl_ICONV_H_DEFAULTS])
+       if test -n "$am_cv_proto_iconv_arg1"; then
+         ICONV_CONST="const"
+       fi
+      ])
+  fi
+])

m4/lib-ld.m4

+# lib-ld.m4 serial 6
+dnl Copyright (C) 1996-2003, 2009-2014 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl Subroutines of libtool.m4,
+dnl with replacements s/_*LT_PATH/AC_LIB_PROG/ and s/lt_/acl_/ to avoid
+dnl collision with libtool.m4.
+
+dnl From libtool-2.4. Sets the variable with_gnu_ld to yes or no.
+AC_DEFUN([AC_LIB_PROG_LD_GNU],
+[AC_CACHE_CHECK([if the linker ($LD) is GNU ld], [acl_cv_prog_gnu_ld],
+[# I'd rather use --version here, but apparently some GNU lds only accept -v.
+case `$LD -v 2>&1 </dev/null` in
+*GNU* | *'with BFD'*)
+  acl_cv_prog_gnu_ld=yes
+  ;;
+*)
+  acl_cv_prog_gnu_ld=no
+  ;;
+esac])
+with_gnu_ld=$acl_cv_prog_gnu_ld
+])
+
+dnl From libtool-2.4. Sets the variable LD.
+AC_DEFUN([AC_LIB_PROG_LD],
+[AC_REQUIRE([AC_PROG_CC])dnl
+AC_REQUIRE([AC_CANONICAL_HOST])dnl
+
+AC_ARG_WITH([gnu-ld],
+    [AS_HELP_STRING([--with-gnu-ld],
+        [assume the C compiler uses GNU ld [default=no]])],
+    [test "$withval" = no || with_gnu_ld=yes],
+    [with_gnu_ld=no])dnl
+
+# Prepare PATH_SEPARATOR.
+# The user is always right.
+if test "${PATH_SEPARATOR+set}" != set; then
+  # Determine PATH_SEPARATOR by trying to find /bin/sh in a PATH which
+  # contains only /bin. Note that ksh looks also at the FPATH variable,
+  # so we have to set that as well for the test.
+  PATH_SEPARATOR=:
+  (PATH='/bin;/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 \
+    && { (PATH='/bin:/bin'; FPATH=$PATH; sh -c :) >/dev/null 2>&1 \
+           || PATH_SEPARATOR=';'
+       }
+fi
+
+ac_prog=ld
+if test "$GCC" = yes; then
+  # Check if gcc -print-prog-name=ld gives a path.
+  AC_MSG_CHECKING([for ld used by $CC])
+  case $host in
+  *-*-mingw*)
+    # gcc leaves a trailing carriage return which upsets mingw
+    ac_prog=`($CC -print-prog-name=ld) 2>&5 | tr -d '\015'` ;;
+  *)
+    ac_prog=`($CC -print-prog-name=ld) 2>&5` ;;
+  esac
+  case $ac_prog in
+    # Accept absolute paths.
+    [[\\/]]* | ?:[[\\/]]*)
+      re_direlt='/[[^/]][[^/]]*/\.\./'
+      # Canonicalize the pathname of ld
+      ac_prog=`echo "$ac_prog"| sed 's%\\\\%/%g'`
+      while echo "$ac_prog" | grep "$re_direlt" > /dev/null 2>&1; do
+        ac_prog=`echo $ac_prog| sed "s%$re_direlt%/%"`
+      done
+      test -z "$LD" && LD="$ac_prog"
+      ;;
+  "")
+    # If it fails, then pretend we aren't using GCC.
+    ac_prog=ld
+    ;;
+  *)
+    # If it is relative, then search for the first ld in PATH.
+    with_gnu_ld=unknown
+    ;;
+  esac
+elif test "$with_gnu_ld" = yes; then
+  AC_MSG_CHECKING([for GNU ld])
+else
+  AC_MSG_CHECKING([for non-GNU ld])
+fi
+AC_CACHE_VAL([acl_cv_path_LD],
+[if test -z "$LD"; then
+  acl_save_ifs="$IFS"; IFS=$PATH_SEPARATOR
+  for ac_dir in $PATH; do
+    IFS="$acl_save_ifs"
+    test -z "$ac_dir" && ac_dir=.
+    if test -f "$ac_dir/$ac_prog" || test -f "$ac_dir/$ac_prog$ac_exeext"; then
+      acl_cv_path_LD="$ac_dir/$ac_prog"
+      # Check to see if the program is GNU ld.  I'd rather use --version,
+      # but apparently some variants of GNU ld only accept -v.
+      # Break only if it was the GNU/non-GNU ld that we prefer.
+      case `"$acl_cv_path_LD" -v 2>&1 </dev/null` in
+      *GNU* | *'with BFD'*)
+        test "$with_gnu_ld" != no && break
+        ;;
+      *)
+        test "$with_gnu_ld" != yes && break
+        ;;
+      esac
+    fi
+  done
+  IFS="$acl_save_ifs"
+else
+  acl_cv_path_LD="$LD" # Let the user override the test with a path.
+fi])
+LD="$acl_cv_path_LD"
+if test -n "$LD"; then
+  AC_MSG_RESULT([$LD])
+else
+  AC_MSG_RESULT([no])
+fi
+test -z "$LD" && AC_MSG_ERROR([no acceptable ld found in \$PATH])
+AC_LIB_PROG_LD_GNU
+])

m4/lib-prefix.m4

+# lib-prefix.m4 serial 7 (gettext-0.18)
+dnl Copyright (C) 2001-2005, 2008-2014 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+dnl From Bruno Haible.
+
+dnl AC_LIB_ARG_WITH is synonymous to AC_ARG_WITH in autoconf-2.13, and
+dnl similar to AC_ARG_WITH in autoconf 2.52...2.57 except that is doesn't
+dnl require excessive bracketing.
+ifdef([AC_HELP_STRING],
+[AC_DEFUN([AC_LIB_ARG_WITH], [AC_ARG_WITH([$1],[[$2]],[$3],[$4])])],
+[AC_DEFUN([AC_][LIB_ARG_WITH], [AC_ARG_WITH([$1],[$2],[$3],[$4])])])
+
+dnl AC_LIB_PREFIX adds to the CPPFLAGS and LDFLAGS the flags that are needed
+dnl to access previously installed libraries. The basic assumption is that
+dnl a user will want packages to use other packages he previously installed
+dnl with the same --prefix option.
+dnl This macro is not needed if only AC_LIB_LINKFLAGS is used to locate
+dnl libraries, but is otherwise very convenient.
+AC_DEFUN([AC_LIB_PREFIX],
+[
+  AC_BEFORE([$0], [AC_LIB_LINKFLAGS])
+  AC_REQUIRE([AC_PROG_CC])
+  AC_REQUIRE([AC_CANONICAL_HOST])
+  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
+  AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+  dnl By default, look in $includedir and $libdir.
+  use_additional=yes
+  AC_LIB_WITH_FINAL_PREFIX([
+    eval additional_includedir=\"$includedir\"
+    eval additional_libdir=\"$libdir\"
+  ])
+  AC_LIB_ARG_WITH([lib-prefix],
+[  --with-lib-prefix[=DIR] search for libraries in DIR/include and DIR/lib
+  --without-lib-prefix    don't search for libraries in includedir and libdir],
+[
+    if test "X$withval" = "Xno"; then
+      use_additional=no
+    else
+      if test "X$withval" = "X"; then
+        AC_LIB_WITH_FINAL_PREFIX([
+          eval additional_includedir=\"$includedir\"
+          eval additional_libdir=\"$libdir\"
+        ])
+      else
+        additional_includedir="$withval/include"
+        additional_libdir="$withval/$acl_libdirstem"
+      fi
+    fi
+])
+  if test $use_additional = yes; then
+    dnl Potentially add $additional_includedir to $CPPFLAGS.
+    dnl But don't add it
+    dnl   1. if it's the standard /usr/include,
+    dnl   2. if it's already present in $CPPFLAGS,
+    dnl   3. if it's /usr/local/include and we are using GCC on Linux,
+    dnl   4. if it doesn't exist as a directory.
+    if test "X$additional_includedir" != "X/usr/include"; then
+      haveit=
+      for x in $CPPFLAGS; do
+        AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+        if test "X$x" = "X-I$additional_includedir"; then
+          haveit=yes
+          break
+        fi
+      done
+      if test -z "$haveit"; then
+        if test "X$additional_includedir" = "X/usr/local/include"; then
+          if test -n "$GCC"; then
+            case $host_os in
+              linux* | gnu* | k*bsd*-gnu) haveit=yes;;
+            esac
+          fi
+        fi
+        if test -z "$haveit"; then
+          if test -d "$additional_includedir"; then
+            dnl Really add $additional_includedir to $CPPFLAGS.
+            CPPFLAGS="${CPPFLAGS}${CPPFLAGS:+ }-I$additional_includedir"
+          fi
+        fi
+      fi
+    fi
+    dnl Potentially add $additional_libdir to $LDFLAGS.
+    dnl But don't add it
+    dnl   1. if it's the standard /usr/lib,
+    dnl   2. if it's already present in $LDFLAGS,
+    dnl   3. if it's /usr/local/lib and we are using GCC on Linux,
+    dnl   4. if it doesn't exist as a directory.
+    if test "X$additional_libdir" != "X/usr/$acl_libdirstem"; then
+      haveit=
+      for x in $LDFLAGS; do
+        AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+        if test "X$x" = "X-L$additional_libdir"; then
+          haveit=yes
+          break
+        fi
+      done
+      if test -z "$haveit"; then
+        if test "X$additional_libdir" = "X/usr/local/$acl_libdirstem"; then
+          if test -n "$GCC"; then
+            case $host_os in
+              linux*) haveit=yes;;
+            esac
+          fi
+        fi
+        if test -z "$haveit"; then
+          if test -d "$additional_libdir"; then
+            dnl Really add $additional_libdir to $LDFLAGS.
+            LDFLAGS="${LDFLAGS}${LDFLAGS:+ }-L$additional_libdir"
+          fi
+        fi
+      fi
+    fi
+  fi
+])
+
+dnl AC_LIB_PREPARE_PREFIX creates variables acl_final_prefix,
+dnl acl_final_exec_prefix, containing the values to which $prefix and
+dnl $exec_prefix will expand at the end of the configure script.
+AC_DEFUN([AC_LIB_PREPARE_PREFIX],
+[
+  dnl Unfortunately, prefix and exec_prefix get only finally determined
+  dnl at the end of configure.
+  if test "X$prefix" = "XNONE"; then
+    acl_final_prefix="$ac_default_prefix"
+  else
+    acl_final_prefix="$prefix"
+  fi
+  if test "X$exec_prefix" = "XNONE"; then
+    acl_final_exec_prefix='${prefix}'
+  else
+    acl_final_exec_prefix="$exec_prefix"
+  fi
+  acl_save_prefix="$prefix"
+  prefix="$acl_final_prefix"
+  eval acl_final_exec_prefix=\"$acl_final_exec_prefix\"
+  prefix="$acl_save_prefix"
+])
+
+dnl AC_LIB_WITH_FINAL_PREFIX([statement]) evaluates statement, with the
+dnl variables prefix and exec_prefix bound to the values they will have
+dnl at the end of the configure script.
+AC_DEFUN([AC_LIB_WITH_FINAL_PREFIX],
+[
+  acl_save_prefix="$prefix"
+  prefix="$acl_final_prefix"
+  acl_save_exec_prefix="$exec_prefix"
+  exec_prefix="$acl_final_exec_prefix"
+  $1
+  exec_prefix="$acl_save_exec_prefix"
+  prefix="$acl_save_prefix"
+])
+
+dnl AC_LIB_PREPARE_MULTILIB creates
+dnl - a variable acl_libdirstem, containing the basename of the libdir, either
+dnl   "lib" or "lib64" or "lib/64",
+dnl - a variable acl_libdirstem2, as a secondary possible value for
+dnl   acl_libdirstem, either the same as acl_libdirstem or "lib/sparcv9" or
+dnl   "lib/amd64".
+AC_DEFUN([AC_LIB_PREPARE_MULTILIB],
+[
+  dnl There is no formal standard regarding lib and lib64.
+  dnl On glibc systems, the current practice is that on a system supporting
+  dnl 32-bit and 64-bit instruction sets or ABIs, 64-bit libraries go under
+  dnl $prefix/lib64 and 32-bit libraries go under $prefix/lib. We determine
+  dnl the compiler's default mode by looking at the compiler's library search
+  dnl path. If at least one of its elements ends in /lib64 or points to a
+  dnl directory whose absolute pathname ends in /lib64, we assume a 64-bit ABI.
+  dnl Otherwise we use the default, namely "lib".
+  dnl On Solaris systems, the current practice is that on a system supporting
+  dnl 32-bit and 64-bit instruction sets or ABIs, 64-bit libraries go under
+  dnl $prefix/lib/64 (which is a symlink to either $prefix/lib/sparcv9 or
+  dnl $prefix/lib/amd64) and 32-bit libraries go under $prefix/lib.
+  AC_REQUIRE([AC_CANONICAL_HOST])
+  acl_libdirstem=lib
+  acl_libdirstem2=
+  case "$host_os" in
+    solaris*)
+      dnl See Solaris 10 Software Developer Collection > Solaris 64-bit Developer's Guide > The Development Environment
+      dnl <http://docs.sun.com/app/docs/doc/816-5138/dev-env?l=en&a=view>.
+      dnl "Portable Makefiles should refer to any library directories using the 64 symbolic link."
+      dnl But we want to recognize the sparcv9 or amd64 subdirectory also if the
+      dnl symlink is missing, so we set acl_libdirstem2 too.
+      AC_CACHE_CHECK([for 64-bit host], [gl_cv_solaris_64bit],
+        [AC_EGREP_CPP([sixtyfour bits], [
+#ifdef _LP64
+sixtyfour bits
+#endif
+           ], [gl_cv_solaris_64bit=yes], [gl_cv_solaris_64bit=no])
+        ])
+      if test $gl_cv_solaris_64bit = yes; then
+        acl_libdirstem=lib/64
+        case "$host_cpu" in
+          sparc*)        acl_libdirstem2=lib/sparcv9 ;;
+          i*86 | x86_64) acl_libdirstem2=lib/amd64 ;;
+        esac
+      fi
+      ;;
+    *)
+      searchpath=`(LC_ALL=C $CC -print-search-dirs) 2>/dev/null | sed -n -e 's,^libraries: ,,p' | sed -e 's,^=,,'`
+      if test -n "$searchpath"; then
+        acl_save_IFS="${IFS= 	}"; IFS=":"
+        for searchdir in $searchpath; do
+          if test -d "$searchdir"; then
+            case "$searchdir" in
+              */lib64/ | */lib64 ) acl_libdirstem=lib64 ;;
+              */../ | */.. )
+                # Better ignore directories of this form. They are misleading.
+                ;;
+              *) searchdir=`cd "$searchdir" && pwd`
+                 case "$searchdir" in
+                   */lib64 ) acl_libdirstem=lib64 ;;
+                 esac ;;
+            esac
+          fi
+        done
+        IFS="$acl_save_IFS"
+      fi
+      ;;
+  esac
+  test -n "$acl_libdirstem2" || acl_libdirstem2="$acl_libdirstem"
+])