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-rwxr-xr-xcommon/m4/lib-link.m4554
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diff --git a/common/m4/lib-link.m4 b/common/m4/lib-link.m4
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--- /dev/null
+++ b/common/m4/lib-link.m4
@@ -0,0 +1,554 @@
+# lib-link.m4 serial 3 (gettext-0.11.3)
+dnl Copyright (C) 2001-2002 Free Software Foundation, Inc.
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License. As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
+
+dnl From Bruno Haible.
+
+dnl AC_LIB_LINKFLAGS(name [, dependencies]) searches for libname and
+dnl the libraries corresponding to explicit and implicit dependencies.
+dnl Sets and AC_SUBSTs the LIB${NAME} and LTLIB${NAME} variables and
+dnl augments the CPPFLAGS variable.
+AC_DEFUN([AC_LIB_LINKFLAGS],
+[
+ AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+ AC_REQUIRE([AC_LIB_RPATH])
+ define([Name],[translit([$1],[./-], [___])])
+ define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
+ [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
+ AC_CACHE_CHECK([how to link with lib[]$1], [ac_cv_lib[]Name[]_libs], [
+ AC_LIB_LINKFLAGS_BODY([$1], [$2])
+ ac_cv_lib[]Name[]_libs="$LIB[]NAME"
+ ac_cv_lib[]Name[]_ltlibs="$LTLIB[]NAME"
+ ac_cv_lib[]Name[]_cppflags="$INC[]NAME"
+ ])
+ LIB[]NAME="$ac_cv_lib[]Name[]_libs"
+ LTLIB[]NAME="$ac_cv_lib[]Name[]_ltlibs"
+ INC[]NAME="$ac_cv_lib[]Name[]_cppflags"
+ AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)
+ AC_SUBST([LIB]NAME)
+ AC_SUBST([LTLIB]NAME)
+ dnl Also set HAVE_LIB[]NAME so that AC_LIB_HAVE_LINKFLAGS can reuse the
+ dnl results of this search when this library appears as a dependency.
+ HAVE_LIB[]NAME=yes
+ undefine([Name])
+ undefine([NAME])
+])
+
+dnl AC_LIB_HAVE_LINKFLAGS(name, dependencies, includes, testcode)
+dnl searches for libname and the libraries corresponding to explicit and
+dnl implicit dependencies, together with the specified include files and
+dnl the ability to compile and link the specified testcode. If found, it
+dnl sets and AC_SUBSTs HAVE_LIB${NAME}=yes and the LIB${NAME} and
+dnl LTLIB${NAME} variables and augments the CPPFLAGS variable, and
+dnl #defines HAVE_LIB${NAME} to 1. Otherwise, it sets and AC_SUBSTs
+dnl HAVE_LIB${NAME}=no and LIB${NAME} and LTLIB${NAME} to empty.
+AC_DEFUN([AC_LIB_HAVE_LINKFLAGS],
+[
+ AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+ AC_REQUIRE([AC_LIB_RPATH])
+ define([Name],[translit([$1],[./-], [___])])
+ define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
+ [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
+
+ dnl Search for lib[]Name and define LIB[]NAME, LTLIB[]NAME and INC[]NAME
+ dnl accordingly.
+ AC_LIB_LINKFLAGS_BODY([$1], [$2])
+
+ dnl Add $INC[]NAME to CPPFLAGS before performing the following checks,
+ dnl because if the user has installed lib[]Name and not disabled its use
+ dnl via --without-lib[]Name-prefix, he wants to use it.
+ ac_save_CPPFLAGS="$CPPFLAGS"
+ AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)
+
+ AC_CACHE_CHECK([for lib[]$1], [ac_cv_lib[]Name], [
+ ac_save_LIBS="$LIBS"
+ LIBS="$LIBS $LIB[]NAME"
+ AC_TRY_LINK([$3], [$4], [ac_cv_lib[]Name=yes], [ac_cv_lib[]Name=no])
+ LIBS="$ac_save_LIBS"
+ ])
+ if test "$ac_cv_lib[]Name" = yes; then
+ HAVE_LIB[]NAME=yes
+ AC_DEFINE([HAVE_LIB]NAME, 1, [Define if you have the $1 library.])
+ AC_MSG_CHECKING([how to link with lib[]$1])
+ AC_MSG_RESULT([$LIB[]NAME])
+ else
+ HAVE_LIB[]NAME=no
+ dnl If $LIB[]NAME didn't lead to a usable library, we don't need
+ dnl $INC[]NAME either.
+ CPPFLAGS="$ac_save_CPPFLAGS"
+ LIB[]NAME=
+ LTLIB[]NAME=
+ fi
+ AC_SUBST([HAVE_LIB]NAME)
+ AC_SUBST([LIB]NAME)
+ AC_SUBST([LTLIB]NAME)
+ undefine([Name])
+ undefine([NAME])
+])
+
+dnl Determine the platform dependent parameters needed to use rpath:
+dnl libext, shlibext, hardcode_libdir_flag_spec, hardcode_libdir_separator,
+dnl hardcode_direct, hardcode_minus_L,
+dnl sys_lib_search_path_spec, sys_lib_dlsearch_path_spec.
+AC_DEFUN([AC_LIB_RPATH],
+[
+ AC_REQUIRE([AC_PROG_CC]) dnl we use $CC, $GCC, $LDFLAGS
+ AC_REQUIRE([AC_LIB_PROG_LD]) dnl we use $LD, $with_gnu_ld
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl we use $host
+ AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT]) dnl we use $ac_aux_dir
+ AC_CACHE_CHECK([for shared library run path origin], acl_cv_rpath, [
+ CC="$CC" GCC="$GCC" LDFLAGS="$LDFLAGS" LD="$LD" with_gnu_ld="$with_gnu_ld" \
+ ${CONFIG_SHELL-/bin/sh} "$ac_aux_dir/config.rpath" "$host" > conftest.sh
+ . ./conftest.sh
+ rm -f ./conftest.sh
+ acl_cv_rpath=done
+ ])
+ wl="$acl_cv_wl"
+ libext="$acl_cv_libext"
+ shlibext="$acl_cv_shlibext"
+ hardcode_libdir_flag_spec="$acl_cv_hardcode_libdir_flag_spec"
+ hardcode_libdir_separator="$acl_cv_hardcode_libdir_separator"
+ hardcode_direct="$acl_cv_hardcode_direct"
+ hardcode_minus_L="$acl_cv_hardcode_minus_L"
+ sys_lib_search_path_spec="$acl_cv_sys_lib_search_path_spec"
+ sys_lib_dlsearch_path_spec="$acl_cv_sys_lib_dlsearch_path_spec"
+ dnl Determine whether the user wants rpath handling at all.
+ AC_ARG_ENABLE(rpath,
+ [ --disable-rpath do not hardcode runtime library paths],
+ :, enable_rpath=yes)
+])
+
+dnl AC_LIB_LINKFLAGS_BODY(name [, dependencies]) searches for libname and
+dnl the libraries corresponding to explicit and implicit dependencies.
+dnl Sets the LIB${NAME}, LTLIB${NAME} and INC${NAME} variables.
+AC_DEFUN([AC_LIB_LINKFLAGS_BODY],
+[
+ define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
+ [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
+ 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_ARG_WITH([lib$1-prefix],
+[ --with-lib$1-prefix[=DIR] search for lib$1 in DIR/include and DIR/lib
+ --without-lib$1-prefix don't search for lib$1 in includedir and libdir],
+[
+ if test "X$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/lib"
+ fi
+ fi
+])
+ dnl Search the library and its dependencies in $additional_libdir and
+ dnl $LDFLAGS. Using breadth-first-seach.
+ LIB[]NAME=
+ LTLIB[]NAME=
+ INC[]NAME=
+ rpathdirs=
+ ltrpathdirs=
+ names_already_handled=
+ names_next_round='$1 $2'
+ while test -n "$names_next_round"; do
+ names_this_round="$names_next_round"
+ names_next_round=
+ for name in $names_this_round; do
+ already_handled=
+ for n in $names_already_handled; do
+ if test "$n" = "$name"; then
+ already_handled=yes
+ break
+ fi
+ done
+ if test -z "$already_handled"; then
+ names_already_handled="$names_already_handled $name"
+ dnl See if it was already located by an earlier AC_LIB_LINKFLAGS
+ dnl or AC_LIB_HAVE_LINKFLAGS call.
+ uppername=`echo "$name" | sed -e 'y|abcdefghijklmnopqrstuvwxyz./-|ABCDEFGHIJKLMNOPQRSTUVWXYZ___|'`
+ eval value=\"\$HAVE_LIB$uppername\"
+ if test -n "$value"; then
+ if test "$value" = yes; then
+ eval value=\"\$LIB$uppername\"
+ test -z "$value" || LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$value"
+ eval value=\"\$LTLIB$uppername\"
+ test -z "$value" || LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$value"
+ else
+ dnl An earlier call to AC_LIB_HAVE_LINKFLAGS has determined
+ dnl that this library doesn't exist. So just drop it.
+ :
+ fi
+ else
+ dnl Search the library lib$name in $additional_libdir and $LDFLAGS
+ dnl and the already constructed $LIBNAME/$LTLIBNAME.
+ found_dir=
+ found_la=
+ found_so=
+ found_a=
+ if test $use_additional = yes; then
+ if test -n "$shlibext" && test -f "$additional_libdir/lib$name.$shlibext"; then
+ found_dir="$additional_libdir"
+ found_so="$additional_libdir/lib$name.$shlibext"
+ if test -f "$additional_libdir/lib$name.la"; then
+ found_la="$additional_libdir/lib$name.la"
+ fi
+ else
+ if test -f "$additional_libdir/lib$name.$libext"; then
+ found_dir="$additional_libdir"
+ found_a="$additional_libdir/lib$name.$libext"
+ if test -f "$additional_libdir/lib$name.la"; then
+ found_la="$additional_libdir/lib$name.la"
+ fi
+ fi
+ fi
+ fi
+ if test "X$found_dir" = "X"; then
+ for x in $LDFLAGS $LTLIB[]NAME; do
+ AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+ case "$x" in
+ -L*)
+ dir=`echo "X$x" | sed -e 's/^X-L//'`
+ if test -n "$shlibext" && test -f "$dir/lib$name.$shlibext"; then
+ found_dir="$dir"
+ found_so="$dir/lib$name.$shlibext"
+ if test -f "$dir/lib$name.la"; then
+ found_la="$dir/lib$name.la"
+ fi
+ else
+ if test -f "$dir/lib$name.$libext"; then
+ found_dir="$dir"
+ found_a="$dir/lib$name.$libext"
+ if test -f "$dir/lib$name.la"; then
+ found_la="$dir/lib$name.la"
+ fi
+ fi
+ fi
+ ;;
+ esac
+ if test "X$found_dir" != "X"; then
+ break
+ fi
+ done
+ fi
+ if test "X$found_dir" != "X"; then
+ dnl Found the library.
+ LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$found_dir -l$name"
+ if test "X$found_so" != "X"; then
+ dnl Linking with a shared library. We attempt to hardcode its
+ dnl directory into the executable's runpath, unless it's the
+ dnl standard /usr/lib.
+ if test "$enable_rpath" = no || test "X$found_dir" = "X/usr/lib"; then
+ dnl No hardcoding is needed.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
+ else
+ dnl Use an explicit option to hardcode DIR into the resulting
+ dnl binary.
+ dnl Potentially add DIR to ltrpathdirs.
+ dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
+ haveit=
+ for x in $ltrpathdirs; do
+ if test "X$x" = "X$found_dir"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ ltrpathdirs="$ltrpathdirs $found_dir"
+ fi
+ dnl The hardcoding into $LIBNAME is system dependent.
+ if test "$hardcode_direct" = yes; then
+ dnl Using DIR/libNAME.so during linking hardcodes DIR into the
+ dnl resulting binary.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
+ else
+ if test -n "$hardcode_libdir_flag_spec" && test "$hardcode_minus_L" = no; then
+ dnl Use an explicit option to hardcode DIR into the resulting
+ dnl binary.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
+ dnl Potentially add DIR to rpathdirs.
+ dnl The rpathdirs will be appended to $LIBNAME at the end.
+ haveit=
+ for x in $rpathdirs; do
+ if test "X$x" = "X$found_dir"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ rpathdirs="$rpathdirs $found_dir"
+ fi
+ else
+ dnl Rely on "-L$found_dir".
+ dnl But don't add it if it's already contained in the LDFLAGS
+ dnl or the already constructed $LIBNAME
+ haveit=
+ for x in $LDFLAGS $LIB[]NAME; do
+ AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+ if test "X$x" = "X-L$found_dir"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir"
+ fi
+ if test "$hardcode_minus_L" != no; then
+ dnl FIXME: Not sure whether we should use
+ dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
+ dnl here.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
+ else
+ dnl We cannot use $hardcode_runpath_var and LD_RUN_PATH
+ dnl here, because this doesn't fit in flags passed to the
+ dnl compiler. So give up. No hardcoding. This affects only
+ dnl very old systems.
+ dnl FIXME: Not sure whether we should use
+ dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
+ dnl here.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
+ fi
+ fi
+ fi
+ fi
+ else
+ if test "X$found_a" != "X"; then
+ dnl Linking with a static library.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_a"
+ else
+ dnl We shouldn't come here, but anyway it's good to have a
+ dnl fallback.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir -l$name"
+ fi
+ fi
+ dnl Assume the include files are nearby.
+ additional_includedir=
+ case "$found_dir" in
+ */lib | */lib/)
+ basedir=`echo "X$found_dir" | sed -e 's,^X,,' -e 's,/lib/*$,,'`
+ additional_includedir="$basedir/include"
+ ;;
+ esac
+ if test "X$additional_includedir" != "X"; then
+ dnl Potentially add $additional_includedir to $INCNAME.
+ dnl But don't add it
+ dnl 1. if it's the standard /usr/include,
+ dnl 2. if it's /usr/local/include and we are using GCC on Linux,
+ dnl 3. if it's already present in $CPPFLAGS or the already
+ dnl constructed $INCNAME,
+ dnl 4. if it doesn't exist as a directory.
+ if test "X$additional_includedir" != "X/usr/include"; then
+ haveit=
+ if test "X$additional_includedir" = "X/usr/local/include"; then
+ if test -n "$GCC"; then
+ case $host_os in
+ linux*) haveit=yes;;
+ esac
+ fi
+ fi
+ if test -z "$haveit"; then
+ for x in $CPPFLAGS $INC[]NAME; do
+ AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+ if test "X$x" = "X-I$additional_includedir"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ if test -d "$additional_includedir"; then
+ dnl Really add $additional_includedir to $INCNAME.
+ INC[]NAME="${INC[]NAME}${INC[]NAME:+ }-I$additional_includedir"
+ fi
+ fi
+ fi
+ fi
+ fi
+ dnl Look for dependencies.
+ if test -n "$found_la"; then
+ dnl Read the .la file. It defines the variables
+ dnl dlname, library_names, old_library, dependency_libs, current,
+ dnl age, revision, installed, dlopen, dlpreopen, libdir.
+ save_libdir="$libdir"
+ case "$found_la" in
+ */* | *\\*) . "$found_la" ;;
+ *) . "./$found_la" ;;
+ esac
+ libdir="$save_libdir"
+ dnl We use only dependency_libs.
+ for dep in $dependency_libs; do
+ case "$dep" in
+ -L*)
+ additional_libdir=`echo "X$dep" | sed -e 's/^X-L//'`
+ dnl Potentially add $additional_libdir to $LIBNAME and $LTLIBNAME.
+ dnl But don't add it
+ dnl 1. if it's the standard /usr/lib,
+ dnl 2. if it's /usr/local/lib and we are using GCC on Linux,
+ dnl 3. if it's already present in $LDFLAGS or the already
+ dnl constructed $LIBNAME,
+ dnl 4. if it doesn't exist as a directory.
+ if test "X$additional_libdir" != "X/usr/lib"; then
+ haveit=
+ if test "X$additional_libdir" = "X/usr/local/lib"; then
+ if test -n "$GCC"; then
+ case $host_os in
+ linux*) haveit=yes;;
+ esac
+ fi
+ fi
+ if test -z "$haveit"; then
+ haveit=
+ for x in $LDFLAGS $LIB[]NAME; do
+ AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+ if test "X$x" = "X-L$additional_libdir"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ if test -d "$additional_libdir"; then
+ dnl Really add $additional_libdir to $LIBNAME.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$additional_libdir"
+ fi
+ fi
+ haveit=
+ for x in $LDFLAGS $LTLIB[]NAME; do
+ AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+ if test "X$x" = "X-L$additional_libdir"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ if test -d "$additional_libdir"; then
+ dnl Really add $additional_libdir to $LTLIBNAME.
+ LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$additional_libdir"
+ fi
+ fi
+ fi
+ fi
+ ;;
+ -R*)
+ dir=`echo "X$dep" | sed -e 's/^X-R//'`
+ if test "$enable_rpath" != no; then
+ dnl Potentially add DIR to rpathdirs.
+ dnl The rpathdirs will be appended to $LIBNAME at the end.
+ haveit=
+ for x in $rpathdirs; do
+ if test "X$x" = "X$dir"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ rpathdirs="$rpathdirs $dir"
+ fi
+ dnl Potentially add DIR to ltrpathdirs.
+ dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
+ haveit=
+ for x in $ltrpathdirs; do
+ if test "X$x" = "X$dir"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ ltrpathdirs="$ltrpathdirs $dir"
+ fi
+ fi
+ ;;
+ -l*)
+ dnl Handle this in the next round.
+ names_next_round="$names_next_round "`echo "X$dep" | sed -e 's/^X-l//'`
+ ;;
+ *.la)
+ dnl Handle this in the next round. Throw away the .la's
+ dnl directory; it is already contained in a preceding -L
+ dnl option.
+ names_next_round="$names_next_round "`echo "X$dep" | sed -e 's,^X.*/,,' -e 's,^lib,,' -e 's,\.la$,,'`
+ ;;
+ *)
+ dnl Most likely an immediate library name.
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$dep"
+ LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$dep"
+ ;;
+ esac
+ done
+ fi
+ else
+ dnl Didn't find the library; assume it is in the system directories
+ dnl known to the linker and runtime loader. (All the system
+ dnl directories known to the linker should also be known to the
+ dnl runtime loader, otherwise the system is severely misconfigured.)
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
+ LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-l$name"
+ fi
+ fi
+ fi
+ done
+ done
+ if test "X$rpathdirs" != "X"; then
+ if test -n "$hardcode_libdir_separator"; then
+ dnl Weird platform: only the last -rpath option counts, the user must
+ dnl pass all path elements in one option. We can arrange that for a
+ dnl single library, but not when more than one $LIBNAMEs are used.
+ alldirs=
+ for found_dir in $rpathdirs; do
+ alldirs="${alldirs}${alldirs:+$hardcode_libdir_separator}$found_dir"
+ done
+ dnl Note: hardcode_libdir_flag_spec uses $libdir and $wl.
+ acl_save_libdir="$libdir"
+ libdir="$alldirs"
+ eval flag=\"$hardcode_libdir_flag_spec\"
+ libdir="$acl_save_libdir"
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
+ else
+ dnl The -rpath options are cumulative.
+ for found_dir in $rpathdirs; do
+ acl_save_libdir="$libdir"
+ libdir="$found_dir"
+ eval flag=\"$hardcode_libdir_flag_spec\"
+ libdir="$acl_save_libdir"
+ LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
+ done
+ fi
+ fi
+ if test "X$ltrpathdirs" != "X"; then
+ dnl When using libtool, the option that works for both libraries and
+ dnl executables is -R. The -R options are cumulative.
+ for found_dir in $ltrpathdirs; do
+ LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-R$found_dir"
+ done
+ fi
+])
+
+dnl AC_LIB_APPENDTOVAR(VAR, CONTENTS) appends the elements of CONTENTS to VAR,
+dnl unless already present in VAR.
+dnl Works only for CPPFLAGS, not for LIB* variables because that sometimes
+dnl contains two or three consecutive elements that belong together.
+AC_DEFUN([AC_LIB_APPENDTOVAR],
+[
+ for element in [$2]; do
+ haveit=
+ for x in $[$1]; do
+ AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
+ if test "X$x" = "X$element"; then
+ haveit=yes
+ break
+ fi
+ done
+ if test -z "$haveit"; then
+ [$1]="${[$1]}${[$1]:+ }$element"
+ fi
+ done
+])