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use AM_ICONV for better portability of the library location. structure renaming to be more specific.
author Carl Byington <carl@five-ten-sg.com>
date Thu, 12 Mar 2009 15:17:32 -0700
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152:edebaf0e87d2 153:0b1766da9be8
1 # lib-link.m4 serial 4 (gettext-0.12)
2 dnl Copyright (C) 2001-2003 Free Software Foundation, Inc.
3 dnl This file is free software, distributed under the terms of the GNU
4 dnl General Public License. As a special exception to the GNU General
5 dnl Public License, this file may be distributed as part of a program
6 dnl that contains a configuration script generated by Autoconf, under
7 dnl the same distribution terms as the rest of that program.
8
9 dnl From Bruno Haible.
10
11 dnl AC_LIB_LINKFLAGS(name [, dependencies]) searches for libname and
12 dnl the libraries corresponding to explicit and implicit dependencies.
13 dnl Sets and AC_SUBSTs the LIB${NAME} and LTLIB${NAME} variables and
14 dnl augments the CPPFLAGS variable.
15 AC_DEFUN([AC_LIB_LINKFLAGS],
16 [
17 AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
18 AC_REQUIRE([AC_LIB_RPATH])
19 define([Name],[translit([$1],[./-], [___])])
20 define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
21 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
22 AC_CACHE_CHECK([how to link with lib[]$1], [ac_cv_lib[]Name[]_libs], [
23 AC_LIB_LINKFLAGS_BODY([$1], [$2])
24 ac_cv_lib[]Name[]_libs="$LIB[]NAME"
25 ac_cv_lib[]Name[]_ltlibs="$LTLIB[]NAME"
26 ac_cv_lib[]Name[]_cppflags="$INC[]NAME"
27 ])
28 LIB[]NAME="$ac_cv_lib[]Name[]_libs"
29 LTLIB[]NAME="$ac_cv_lib[]Name[]_ltlibs"
30 INC[]NAME="$ac_cv_lib[]Name[]_cppflags"
31 AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)
32 AC_SUBST([LIB]NAME)
33 AC_SUBST([LTLIB]NAME)
34 dnl Also set HAVE_LIB[]NAME so that AC_LIB_HAVE_LINKFLAGS can reuse the
35 dnl results of this search when this library appears as a dependency.
36 HAVE_LIB[]NAME=yes
37 undefine([Name])
38 undefine([NAME])
39 ])
40
41 dnl AC_LIB_HAVE_LINKFLAGS(name, dependencies, includes, testcode)
42 dnl searches for libname and the libraries corresponding to explicit and
43 dnl implicit dependencies, together with the specified include files and
44 dnl the ability to compile and link the specified testcode. If found, it
45 dnl sets and AC_SUBSTs HAVE_LIB${NAME}=yes and the LIB${NAME} and
46 dnl LTLIB${NAME} variables and augments the CPPFLAGS variable, and
47 dnl #defines HAVE_LIB${NAME} to 1. Otherwise, it sets and AC_SUBSTs
48 dnl HAVE_LIB${NAME}=no and LIB${NAME} and LTLIB${NAME} to empty.
49 AC_DEFUN([AC_LIB_HAVE_LINKFLAGS],
50 [
51 AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
52 AC_REQUIRE([AC_LIB_RPATH])
53 define([Name],[translit([$1],[./-], [___])])
54 define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
55 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
56
57 dnl Search for lib[]Name and define LIB[]NAME, LTLIB[]NAME and INC[]NAME
58 dnl accordingly.
59 AC_LIB_LINKFLAGS_BODY([$1], [$2])
60
61 dnl Add $INC[]NAME to CPPFLAGS before performing the following checks,
62 dnl because if the user has installed lib[]Name and not disabled its use
63 dnl via --without-lib[]Name-prefix, he wants to use it.
64 ac_save_CPPFLAGS="$CPPFLAGS"
65 AC_LIB_APPENDTOVAR([CPPFLAGS], [$INC]NAME)
66
67 AC_CACHE_CHECK([for lib[]$1], [ac_cv_lib[]Name], [
68 ac_save_LIBS="$LIBS"
69 LIBS="$LIBS $LIB[]NAME"
70 AC_TRY_LINK([$3], [$4], [ac_cv_lib[]Name=yes], [ac_cv_lib[]Name=no])
71 LIBS="$ac_save_LIBS"
72 ])
73 if test "$ac_cv_lib[]Name" = yes; then
74 HAVE_LIB[]NAME=yes
75 AC_DEFINE([HAVE_LIB]NAME, 1, [Define if you have the $1 library.])
76 AC_MSG_CHECKING([how to link with lib[]$1])
77 AC_MSG_RESULT([$LIB[]NAME])
78 else
79 HAVE_LIB[]NAME=no
80 dnl If $LIB[]NAME didn't lead to a usable library, we don't need
81 dnl $INC[]NAME either.
82 CPPFLAGS="$ac_save_CPPFLAGS"
83 LIB[]NAME=
84 LTLIB[]NAME=
85 fi
86 AC_SUBST([HAVE_LIB]NAME)
87 AC_SUBST([LIB]NAME)
88 AC_SUBST([LTLIB]NAME)
89 undefine([Name])
90 undefine([NAME])
91 ])
92
93 dnl Determine the platform dependent parameters needed to use rpath:
94 dnl libext, shlibext, hardcode_libdir_flag_spec, hardcode_libdir_separator,
95 dnl hardcode_direct, hardcode_minus_L.
96 AC_DEFUN([AC_LIB_RPATH],
97 [
98 AC_REQUIRE([AC_PROG_CC]) dnl we use $CC, $GCC, $LDFLAGS
99 AC_REQUIRE([AC_LIB_PROG_LD]) dnl we use $LD, $with_gnu_ld
100 AC_REQUIRE([AC_CANONICAL_HOST]) dnl we use $host
101 AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT]) dnl we use $ac_aux_dir
102 AC_CACHE_CHECK([for shared library run path origin], acl_cv_rpath, [
103 CC="$CC" GCC="$GCC" LDFLAGS="$LDFLAGS" LD="$LD" with_gnu_ld="$with_gnu_ld" \
104 ${CONFIG_SHELL-/bin/sh} "$ac_aux_dir/config.rpath" "$host" > conftest.sh
105 . ./conftest.sh
106 rm -f ./conftest.sh
107 acl_cv_rpath=done
108 ])
109 wl="$acl_cv_wl"
110 libext="$acl_cv_libext"
111 shlibext="$acl_cv_shlibext"
112 hardcode_libdir_flag_spec="$acl_cv_hardcode_libdir_flag_spec"
113 hardcode_libdir_separator="$acl_cv_hardcode_libdir_separator"
114 hardcode_direct="$acl_cv_hardcode_direct"
115 hardcode_minus_L="$acl_cv_hardcode_minus_L"
116 dnl Determine whether the user wants rpath handling at all.
117 AC_ARG_ENABLE(rpath,
118 [ --disable-rpath do not hardcode runtime library paths],
119 :, enable_rpath=yes)
120 ])
121
122 dnl AC_LIB_LINKFLAGS_BODY(name [, dependencies]) searches for libname and
123 dnl the libraries corresponding to explicit and implicit dependencies.
124 dnl Sets the LIB${NAME}, LTLIB${NAME} and INC${NAME} variables.
125 AC_DEFUN([AC_LIB_LINKFLAGS_BODY],
126 [
127 define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
128 [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
129 dnl By default, look in $includedir and $libdir.
130 use_additional=yes
131 AC_LIB_WITH_FINAL_PREFIX([
132 eval additional_includedir=\"$includedir\"
133 eval additional_libdir=\"$libdir\"
134 ])
135 AC_LIB_ARG_WITH([lib$1-prefix],
136 [ --with-lib$1-prefix[=DIR] search for lib$1 in DIR/include and DIR/lib
137 --without-lib$1-prefix don't search for lib$1 in includedir and libdir],
138 [
139 if test "X$withval" = "Xno"; then
140 use_additional=no
141 else
142 if test "X$withval" = "X"; then
143 AC_LIB_WITH_FINAL_PREFIX([
144 eval additional_includedir=\"$includedir\"
145 eval additional_libdir=\"$libdir\"
146 ])
147 else
148 additional_includedir="$withval/include"
149 additional_libdir="$withval/lib"
150 fi
151 fi
152 ])
153 dnl Search the library and its dependencies in $additional_libdir and
154 dnl $LDFLAGS. Using breadth-first-seach.
155 LIB[]NAME=
156 LTLIB[]NAME=
157 INC[]NAME=
158 rpathdirs=
159 ltrpathdirs=
160 names_already_handled=
161 names_next_round='$1 $2'
162 while test -n "$names_next_round"; do
163 names_this_round="$names_next_round"
164 names_next_round=
165 for name in $names_this_round; do
166 already_handled=
167 for n in $names_already_handled; do
168 if test "$n" = "$name"; then
169 already_handled=yes
170 break
171 fi
172 done
173 if test -z "$already_handled"; then
174 names_already_handled="$names_already_handled $name"
175 dnl See if it was already located by an earlier AC_LIB_LINKFLAGS
176 dnl or AC_LIB_HAVE_LINKFLAGS call.
177 uppername=`echo "$name" | sed -e 'y|abcdefghijklmnopqrstuvwxyz./-|ABCDEFGHIJKLMNOPQRSTUVWXYZ___|'`
178 eval value=\"\$HAVE_LIB$uppername\"
179 if test -n "$value"; then
180 if test "$value" = yes; then
181 eval value=\"\$LIB$uppername\"
182 test -z "$value" || LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$value"
183 eval value=\"\$LTLIB$uppername\"
184 test -z "$value" || LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$value"
185 else
186 dnl An earlier call to AC_LIB_HAVE_LINKFLAGS has determined
187 dnl that this library doesn't exist. So just drop it.
188 :
189 fi
190 else
191 dnl Search the library lib$name in $additional_libdir and $LDFLAGS
192 dnl and the already constructed $LIBNAME/$LTLIBNAME.
193 found_dir=
194 found_la=
195 found_so=
196 found_a=
197 if test $use_additional = yes; then
198 if test -n "$shlibext" && test -f "$additional_libdir/lib$name.$shlibext"; then
199 found_dir="$additional_libdir"
200 found_so="$additional_libdir/lib$name.$shlibext"
201 if test -f "$additional_libdir/lib$name.la"; then
202 found_la="$additional_libdir/lib$name.la"
203 fi
204 else
205 if test -f "$additional_libdir/lib$name.$libext"; then
206 found_dir="$additional_libdir"
207 found_a="$additional_libdir/lib$name.$libext"
208 if test -f "$additional_libdir/lib$name.la"; then
209 found_la="$additional_libdir/lib$name.la"
210 fi
211 fi
212 fi
213 fi
214 if test "X$found_dir" = "X"; then
215 for x in $LDFLAGS $LTLIB[]NAME; do
216 AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
217 case "$x" in
218 -L*)
219 dir=`echo "X$x" | sed -e 's/^X-L//'`
220 if test -n "$shlibext" && test -f "$dir/lib$name.$shlibext"; then
221 found_dir="$dir"
222 found_so="$dir/lib$name.$shlibext"
223 if test -f "$dir/lib$name.la"; then
224 found_la="$dir/lib$name.la"
225 fi
226 else
227 if test -f "$dir/lib$name.$libext"; then
228 found_dir="$dir"
229 found_a="$dir/lib$name.$libext"
230 if test -f "$dir/lib$name.la"; then
231 found_la="$dir/lib$name.la"
232 fi
233 fi
234 fi
235 ;;
236 esac
237 if test "X$found_dir" != "X"; then
238 break
239 fi
240 done
241 fi
242 if test "X$found_dir" != "X"; then
243 dnl Found the library.
244 LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$found_dir -l$name"
245 if test "X$found_so" != "X"; then
246 dnl Linking with a shared library. We attempt to hardcode its
247 dnl directory into the executable's runpath, unless it's the
248 dnl standard /usr/lib.
249 if test "$enable_rpath" = no || test "X$found_dir" = "X/usr/lib"; then
250 dnl No hardcoding is needed.
251 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
252 else
253 dnl Use an explicit option to hardcode DIR into the resulting
254 dnl binary.
255 dnl Potentially add DIR to ltrpathdirs.
256 dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
257 haveit=
258 for x in $ltrpathdirs; do
259 if test "X$x" = "X$found_dir"; then
260 haveit=yes
261 break
262 fi
263 done
264 if test -z "$haveit"; then
265 ltrpathdirs="$ltrpathdirs $found_dir"
266 fi
267 dnl The hardcoding into $LIBNAME is system dependent.
268 if test "$hardcode_direct" = yes; then
269 dnl Using DIR/libNAME.so during linking hardcodes DIR into the
270 dnl resulting binary.
271 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
272 else
273 if test -n "$hardcode_libdir_flag_spec" && test "$hardcode_minus_L" = no; then
274 dnl Use an explicit option to hardcode DIR into the resulting
275 dnl binary.
276 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
277 dnl Potentially add DIR to rpathdirs.
278 dnl The rpathdirs will be appended to $LIBNAME at the end.
279 haveit=
280 for x in $rpathdirs; do
281 if test "X$x" = "X$found_dir"; then
282 haveit=yes
283 break
284 fi
285 done
286 if test -z "$haveit"; then
287 rpathdirs="$rpathdirs $found_dir"
288 fi
289 else
290 dnl Rely on "-L$found_dir".
291 dnl But don't add it if it's already contained in the LDFLAGS
292 dnl or the already constructed $LIBNAME
293 haveit=
294 for x in $LDFLAGS $LIB[]NAME; do
295 AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
296 if test "X$x" = "X-L$found_dir"; then
297 haveit=yes
298 break
299 fi
300 done
301 if test -z "$haveit"; then
302 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir"
303 fi
304 if test "$hardcode_minus_L" != no; then
305 dnl FIXME: Not sure whether we should use
306 dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
307 dnl here.
308 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
309 else
310 dnl We cannot use $hardcode_runpath_var and LD_RUN_PATH
311 dnl here, because this doesn't fit in flags passed to the
312 dnl compiler. So give up. No hardcoding. This affects only
313 dnl very old systems.
314 dnl FIXME: Not sure whether we should use
315 dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
316 dnl here.
317 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
318 fi
319 fi
320 fi
321 fi
322 else
323 if test "X$found_a" != "X"; then
324 dnl Linking with a static library.
325 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_a"
326 else
327 dnl We shouldn't come here, but anyway it's good to have a
328 dnl fallback.
329 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir -l$name"
330 fi
331 fi
332 dnl Assume the include files are nearby.
333 additional_includedir=
334 case "$found_dir" in
335 */lib | */lib/)
336 basedir=`echo "X$found_dir" | sed -e 's,^X,,' -e 's,/lib/*$,,'`
337 additional_includedir="$basedir/include"
338 ;;
339 esac
340 if test "X$additional_includedir" != "X"; then
341 dnl Potentially add $additional_includedir to $INCNAME.
342 dnl But don't add it
343 dnl 1. if it's the standard /usr/include,
344 dnl 2. if it's /usr/local/include and we are using GCC on Linux,
345 dnl 3. if it's already present in $CPPFLAGS or the already
346 dnl constructed $INCNAME,
347 dnl 4. if it doesn't exist as a directory.
348 if test "X$additional_includedir" != "X/usr/include"; then
349 haveit=
350 if test "X$additional_includedir" = "X/usr/local/include"; then
351 if test -n "$GCC"; then
352 case $host_os in
353 linux*) haveit=yes;;
354 esac
355 fi
356 fi
357 if test -z "$haveit"; then
358 for x in $CPPFLAGS $INC[]NAME; do
359 AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
360 if test "X$x" = "X-I$additional_includedir"; then
361 haveit=yes
362 break
363 fi
364 done
365 if test -z "$haveit"; then
366 if test -d "$additional_includedir"; then
367 dnl Really add $additional_includedir to $INCNAME.
368 INC[]NAME="${INC[]NAME}${INC[]NAME:+ }-I$additional_includedir"
369 fi
370 fi
371 fi
372 fi
373 fi
374 dnl Look for dependencies.
375 if test -n "$found_la"; then
376 dnl Read the .la file. It defines the variables
377 dnl dlname, library_names, old_library, dependency_libs, current,
378 dnl age, revision, installed, dlopen, dlpreopen, libdir.
379 save_libdir="$libdir"
380 case "$found_la" in
381 */* | *\\*) . "$found_la" ;;
382 *) . "./$found_la" ;;
383 esac
384 libdir="$save_libdir"
385 dnl We use only dependency_libs.
386 for dep in $dependency_libs; do
387 case "$dep" in
388 -L*)
389 additional_libdir=`echo "X$dep" | sed -e 's/^X-L//'`
390 dnl Potentially add $additional_libdir to $LIBNAME and $LTLIBNAME.
391 dnl But don't add it
392 dnl 1. if it's the standard /usr/lib,
393 dnl 2. if it's /usr/local/lib and we are using GCC on Linux,
394 dnl 3. if it's already present in $LDFLAGS or the already
395 dnl constructed $LIBNAME,
396 dnl 4. if it doesn't exist as a directory.
397 if test "X$additional_libdir" != "X/usr/lib"; then
398 haveit=
399 if test "X$additional_libdir" = "X/usr/local/lib"; then
400 if test -n "$GCC"; then
401 case $host_os in
402 linux*) haveit=yes;;
403 esac
404 fi
405 fi
406 if test -z "$haveit"; then
407 haveit=
408 for x in $LDFLAGS $LIB[]NAME; do
409 AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
410 if test "X$x" = "X-L$additional_libdir"; then
411 haveit=yes
412 break
413 fi
414 done
415 if test -z "$haveit"; then
416 if test -d "$additional_libdir"; then
417 dnl Really add $additional_libdir to $LIBNAME.
418 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$additional_libdir"
419 fi
420 fi
421 haveit=
422 for x in $LDFLAGS $LTLIB[]NAME; do
423 AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
424 if test "X$x" = "X-L$additional_libdir"; then
425 haveit=yes
426 break
427 fi
428 done
429 if test -z "$haveit"; then
430 if test -d "$additional_libdir"; then
431 dnl Really add $additional_libdir to $LTLIBNAME.
432 LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$additional_libdir"
433 fi
434 fi
435 fi
436 fi
437 ;;
438 -R*)
439 dir=`echo "X$dep" | sed -e 's/^X-R//'`
440 if test "$enable_rpath" != no; then
441 dnl Potentially add DIR to rpathdirs.
442 dnl The rpathdirs will be appended to $LIBNAME at the end.
443 haveit=
444 for x in $rpathdirs; do
445 if test "X$x" = "X$dir"; then
446 haveit=yes
447 break
448 fi
449 done
450 if test -z "$haveit"; then
451 rpathdirs="$rpathdirs $dir"
452 fi
453 dnl Potentially add DIR to ltrpathdirs.
454 dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
455 haveit=
456 for x in $ltrpathdirs; do
457 if test "X$x" = "X$dir"; then
458 haveit=yes
459 break
460 fi
461 done
462 if test -z "$haveit"; then
463 ltrpathdirs="$ltrpathdirs $dir"
464 fi
465 fi
466 ;;
467 -l*)
468 dnl Handle this in the next round.
469 names_next_round="$names_next_round "`echo "X$dep" | sed -e 's/^X-l//'`
470 ;;
471 *.la)
472 dnl Handle this in the next round. Throw away the .la's
473 dnl directory; it is already contained in a preceding -L
474 dnl option.
475 names_next_round="$names_next_round "`echo "X$dep" | sed -e 's,^X.*/,,' -e 's,^lib,,' -e 's,\.la$,,'`
476 ;;
477 *)
478 dnl Most likely an immediate library name.
479 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$dep"
480 LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$dep"
481 ;;
482 esac
483 done
484 fi
485 else
486 dnl Didn't find the library; assume it is in the system directories
487 dnl known to the linker and runtime loader. (All the system
488 dnl directories known to the linker should also be known to the
489 dnl runtime loader, otherwise the system is severely misconfigured.)
490 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
491 LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-l$name"
492 fi
493 fi
494 fi
495 done
496 done
497 if test "X$rpathdirs" != "X"; then
498 if test -n "$hardcode_libdir_separator"; then
499 dnl Weird platform: only the last -rpath option counts, the user must
500 dnl pass all path elements in one option. We can arrange that for a
501 dnl single library, but not when more than one $LIBNAMEs are used.
502 alldirs=
503 for found_dir in $rpathdirs; do
504 alldirs="${alldirs}${alldirs:+$hardcode_libdir_separator}$found_dir"
505 done
506 dnl Note: hardcode_libdir_flag_spec uses $libdir and $wl.
507 acl_save_libdir="$libdir"
508 libdir="$alldirs"
509 eval flag=\"$hardcode_libdir_flag_spec\"
510 libdir="$acl_save_libdir"
511 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
512 else
513 dnl The -rpath options are cumulative.
514 for found_dir in $rpathdirs; do
515 acl_save_libdir="$libdir"
516 libdir="$found_dir"
517 eval flag=\"$hardcode_libdir_flag_spec\"
518 libdir="$acl_save_libdir"
519 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
520 done
521 fi
522 fi
523 if test "X$ltrpathdirs" != "X"; then
524 dnl When using libtool, the option that works for both libraries and
525 dnl executables is -R. The -R options are cumulative.
526 for found_dir in $ltrpathdirs; do
527 LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-R$found_dir"
528 done
529 fi
530 ])
531
532 dnl AC_LIB_APPENDTOVAR(VAR, CONTENTS) appends the elements of CONTENTS to VAR,
533 dnl unless already present in VAR.
534 dnl Works only for CPPFLAGS, not for LIB* variables because that sometimes
535 dnl contains two or three consecutive elements that belong together.
536 AC_DEFUN([AC_LIB_APPENDTOVAR],
537 [
538 for element in [$2]; do
539 haveit=
540 for x in $[$1]; do
541 AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
542 if test "X$x" = "X$element"; then
543 haveit=yes
544 break
545 fi
546 done
547 if test -z "$haveit"; then
548 [$1]="${[$1]}${[$1]:+ }$element"
549 fi
550 done
551 ])