m4/lib-link.m4

   1 # lib-link.m4 serial 9 (gettext-0.16)
   2 dnl Copyright (C) 2001-2006 Free Software Foundation, Inc.
   3 dnl This file is free software; the Free Software Foundation
   4 dnl gives unlimited permission to copy and/or distribute it,
   5 dnl with or without modifications, as long as this notice is preserved.
   6
   7 dnl From Bruno Haible.
   8
   9 AC_PREREQ(2.50)
  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   dnl Tell automake >= 1.10 to complain if config.rpath is missing.
  99   m4_ifdef([AC_REQUIRE_AUX_FILE], [AC_REQUIRE_AUX_FILE([config.rpath])])
 100   AC_REQUIRE([AC_PROG_CC])                dnl we use $CC, $GCC, $LDFLAGS
 101   AC_REQUIRE([AC_LIB_PROG_LD])            dnl we use $LD, $with_gnu_ld
 102   AC_REQUIRE([AC_CANONICAL_HOST])         dnl we use $host
 103   AC_REQUIRE([AC_CONFIG_AUX_DIR_DEFAULT]) dnl we use $ac_aux_dir
 104   AC_CACHE_CHECK([for shared library run path origin], acl_cv_rpath, [
 105     CC="$CC" GCC="$GCC" LDFLAGS="$LDFLAGS" LD="$LD" with_gnu_ld="$with_gnu_ld" \
 106     ${CONFIG_SHELL-/bin/sh} "$ac_aux_dir/config.rpath" "$host" > conftest.sh
 107     . ./conftest.sh
 108     rm -f ./conftest.sh
 109     acl_cv_rpath=done
 110   ])
 111   wl="$acl_cv_wl"
 112   libext="$acl_cv_libext"
 113   shlibext="$acl_cv_shlibext"
 114   hardcode_libdir_flag_spec="$acl_cv_hardcode_libdir_flag_spec"
 115   hardcode_libdir_separator="$acl_cv_hardcode_libdir_separator"
 116   hardcode_direct="$acl_cv_hardcode_direct"
 117   hardcode_minus_L="$acl_cv_hardcode_minus_L"
 118   dnl Determine whether the user wants rpath handling at all.
 119   AC_ARG_ENABLE(rpath,
 120     [  --disable-rpath         do not hardcode runtime library paths],
 121     :, enable_rpath=yes)
 122 ])
 123
 124 dnl AC_LIB_LINKFLAGS_BODY(name [, dependencies]) searches for libname and
 125 dnl the libraries corresponding to explicit and implicit dependencies.
 126 dnl Sets the LIB${NAME}, LTLIB${NAME} and INC${NAME} variables.
 127 AC_DEFUN([AC_LIB_LINKFLAGS_BODY],
 128 [
 129   AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
 130   define([NAME],[translit([$1],[abcdefghijklmnopqrstuvwxyz./-],
 131                                [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])])
 132   dnl By default, look in $includedir and $libdir.
 133   use_additional=yes
 134   AC_LIB_WITH_FINAL_PREFIX([
 135     eval additional_includedir=\"$includedir\"
 136     eval additional_libdir=\"$libdir\"
 137   ])
 138   AC_LIB_ARG_WITH([lib$1-prefix],
 139 [  --with-lib$1-prefix[=DIR]  search for lib$1 in DIR/include and DIR/lib
 140   --without-lib$1-prefix     don't search for lib$1 in includedir and libdir],
 141 [
 142     if test "X$withval" = "Xno"; then
 143       use_additional=no
 144     else
 145       if test "X$withval" = "X"; then
 146         AC_LIB_WITH_FINAL_PREFIX([
 147           eval additional_includedir=\"$includedir\"
 148           eval additional_libdir=\"$libdir\"
 149         ])
 150       else
 151         additional_includedir="$withval/include"
 152         additional_libdir="$withval/$acl_libdirstem"
 153       fi
 154     fi
 155 ])
 156   dnl Search the library and its dependencies in $additional_libdir and
 157   dnl $LDFLAGS. Using breadth-first-seach.
 158   LIB[]NAME=
 159   LTLIB[]NAME=
 160   INC[]NAME=
 161   rpathdirs=
 162   ltrpathdirs=
 163   names_already_handled=
 164   names_next_round='$1 $2'
 165   while test -n "$names_next_round"; do
 166     names_this_round="$names_next_round"
 167     names_next_round=
 168     for name in $names_this_round; do
 169       already_handled=
 170       for n in $names_already_handled; do
 171         if test "$n" = "$name"; then
 172           already_handled=yes
 173           break
 174         fi
 175       done
 176       if test -z "$already_handled"; then
 177         names_already_handled="$names_already_handled $name"
 178         dnl See if it was already located by an earlier AC_LIB_LINKFLAGS
 179         dnl or AC_LIB_HAVE_LINKFLAGS call.
 180         uppername=`echo "$name" | sed -e 'y|abcdefghijklmnopqrstuvwxyz./-|ABCDEFGHIJKLMNOPQRSTUVWXYZ___|'`
 181         eval value=\"\$HAVE_LIB$uppername\"
 182         if test -n "$value"; then
 183           if test "$value" = yes; then
 184             eval value=\"\$LIB$uppername\"
 185             test -z "$value" || LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$value"
 186             eval value=\"\$LTLIB$uppername\"
 187             test -z "$value" || LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$value"
 188           else
 189             dnl An earlier call to AC_LIB_HAVE_LINKFLAGS has determined
 190             dnl that this library doesn't exist. So just drop it.
 191             :
 192           fi
 193         else
 194           dnl Search the library lib$name in $additional_libdir and $LDFLAGS
 195           dnl and the already constructed $LIBNAME/$LTLIBNAME.
 196           found_dir=
 197           found_la=
 198           found_so=
 199           found_a=
 200           if test $use_additional = yes; then
 201             if test -n "$shlibext" \
 202                && { test -f "$additional_libdir/lib$name.$shlibext" \
 203                     || { test "$shlibext" = dll \
 204                          && test -f "$additional_libdir/lib$name.dll.a"; }; }; then
 205               found_dir="$additional_libdir"
 206               if test -f "$additional_libdir/lib$name.$shlibext"; then
 207                 found_so="$additional_libdir/lib$name.$shlibext"
 208               else
 209                 found_so="$additional_libdir/lib$name.dll.a"
 210               fi
 211               if test -f "$additional_libdir/lib$name.la"; then
 212                 found_la="$additional_libdir/lib$name.la"
 213               fi
 214             else
 215               if test -f "$additional_libdir/lib$name.$libext"; then
 216                 found_dir="$additional_libdir"
 217                 found_a="$additional_libdir/lib$name.$libext"
 218                 if test -f "$additional_libdir/lib$name.la"; then
 219                   found_la="$additional_libdir/lib$name.la"
 220                 fi
 221               fi
 222             fi
 223           fi
 224           if test "X$found_dir" = "X"; then
 225             for x in $LDFLAGS $LTLIB[]NAME; do
 226               AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
 227               case "$x" in
 228                 -L*)
 229                   dir=`echo "X$x" | sed -e 's/^X-L//'`
 230                   if test -n "$shlibext" \
 231                      && { test -f "$dir/lib$name.$shlibext" \
 232                           || { test "$shlibext" = dll \
 233                                && test -f "$dir/lib$name.dll.a"; }; }; then
 234                     found_dir="$dir"
 235                     if test -f "$dir/lib$name.$shlibext"; then
 236                       found_so="$dir/lib$name.$shlibext"
 237                     else
 238                       found_so="$dir/lib$name.dll.a"
 239                     fi
 240                     if test -f "$dir/lib$name.la"; then
 241                       found_la="$dir/lib$name.la"
 242                     fi
 243                   else
 244                     if test -f "$dir/lib$name.$libext"; then
 245                       found_dir="$dir"
 246                       found_a="$dir/lib$name.$libext"
 247                       if test -f "$dir/lib$name.la"; then
 248                         found_la="$dir/lib$name.la"
 249                       fi
 250                     fi
 251                   fi
 252                   ;;
 253               esac
 254               if test "X$found_dir" != "X"; then
 255                 break
 256               fi
 257             done
 258           fi
 259           if test "X$found_dir" != "X"; then
 260             dnl Found the library.
 261             LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$found_dir -l$name"
 262             if test "X$found_so" != "X"; then
 263               dnl Linking with a shared library. We attempt to hardcode its
 264               dnl directory into the executable's runpath, unless it's the
 265               dnl standard /usr/lib.
 266               if test "$enable_rpath" = no || test "X$found_dir" = "X/usr/$acl_libdirstem"; then
 267                 dnl No hardcoding is needed.
 268                 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
 269               else
 270                 dnl Use an explicit option to hardcode DIR into the resulting
 271                 dnl binary.
 272                 dnl Potentially add DIR to ltrpathdirs.
 273                 dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
 274                 haveit=
 275                 for x in $ltrpathdirs; do
 276                   if test "X$x" = "X$found_dir"; then
 277                     haveit=yes
 278                     break
 279                   fi
 280                 done
 281                 if test -z "$haveit"; then
 282                   ltrpathdirs="$ltrpathdirs $found_dir"
 283                 fi
 284                 dnl The hardcoding into $LIBNAME is system dependent.
 285                 if test "$hardcode_direct" = yes; then
 286                   dnl Using DIR/libNAME.so during linking hardcodes DIR into the
 287                   dnl resulting binary.
 288                   LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
 289                 else
 290                   if test -n "$hardcode_libdir_flag_spec" && test "$hardcode_minus_L" = no; then
 291                     dnl Use an explicit option to hardcode DIR into the resulting
 292                     dnl binary.
 293                     LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
 294                     dnl Potentially add DIR to rpathdirs.
 295                     dnl The rpathdirs will be appended to $LIBNAME at the end.
 296                     haveit=
 297                     for x in $rpathdirs; do
 298                       if test "X$x" = "X$found_dir"; then
 299                         haveit=yes
 300                         break
 301                       fi
 302                     done
 303                     if test -z "$haveit"; then
 304                       rpathdirs="$rpathdirs $found_dir"
 305                     fi
 306                   else
 307                     dnl Rely on "-L$found_dir".
 308                     dnl But don't add it if it's already contained in the LDFLAGS
 309                     dnl or the already constructed $LIBNAME
 310                     haveit=
 311                     for x in $LDFLAGS $LIB[]NAME; do
 312                       AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
 313                       if test "X$x" = "X-L$found_dir"; then
 314                         haveit=yes
 315                         break
 316                       fi
 317                     done
 318                     if test -z "$haveit"; then
 319                       LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir"
 320                     fi
 321                     if test "$hardcode_minus_L" != no; then
 322                       dnl FIXME: Not sure whether we should use
 323                       dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
 324                       dnl here.
 325                       LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_so"
 326                     else
 327                       dnl We cannot use $hardcode_runpath_var and LD_RUN_PATH
 328                       dnl here, because this doesn't fit in flags passed to the
 329                       dnl compiler. So give up. No hardcoding. This affects only
 330                       dnl very old systems.
 331                       dnl FIXME: Not sure whether we should use
 332                       dnl "-L$found_dir -l$name" or "-L$found_dir $found_so"
 333                       dnl here.
 334                       LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
 335                     fi
 336                   fi
 337                 fi
 338               fi
 339             else
 340               if test "X$found_a" != "X"; then
 341                 dnl Linking with a static library.
 342                 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$found_a"
 343               else
 344                 dnl We shouldn't come here, but anyway it's good to have a
 345                 dnl fallback.
 346                 LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$found_dir -l$name"
 347               fi
 348             fi
 349             dnl Assume the include files are nearby.
 350             additional_includedir=
 351             case "$found_dir" in
 352               */$acl_libdirstem | */$acl_libdirstem/)
 353                 basedir=`echo "X$found_dir" | sed -e 's,^X,,' -e "s,/$acl_libdirstem/"'*$,,'`
 354                 additional_includedir="$basedir/include"
 355                 ;;
 356             esac
 357             if test "X$additional_includedir" != "X"; then
 358               dnl Potentially add $additional_includedir to $INCNAME.
 359               dnl But don't add it
 360               dnl   1. if it's the standard /usr/include,
 361               dnl   2. if it's /usr/local/include and we are using GCC on Linux,
 362               dnl   3. if it's already present in $CPPFLAGS or the already
 363               dnl      constructed $INCNAME,
 364               dnl   4. if it doesn't exist as a directory.
 365               if test "X$additional_includedir" != "X/usr/include"; then
 366                 haveit=
 367                 if test "X$additional_includedir" = "X/usr/local/include"; then
 368                   if test -n "$GCC"; then
 369                     case $host_os in
 370                       linux* | gnu* | k*bsd*-gnu) haveit=yes;;
 371                     esac
 372                   fi
 373                 fi
 374                 if test -z "$haveit"; then
 375                   for x in $CPPFLAGS $INC[]NAME; do
 376                     AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
 377                     if test "X$x" = "X-I$additional_includedir"; then
 378                       haveit=yes
 379                       break
 380                     fi
 381                   done
 382                   if test -z "$haveit"; then
 383                     if test -d "$additional_includedir"; then
 384                       dnl Really add $additional_includedir to $INCNAME.
 385                       INC[]NAME="${INC[]NAME}${INC[]NAME:+ }-I$additional_includedir"
 386                     fi
 387                   fi
 388                 fi
 389               fi
 390             fi
 391             dnl Look for dependencies.
 392             if test -n "$found_la"; then
 393               dnl Read the .la file. It defines the variables
 394               dnl dlname, library_names, old_library, dependency_libs, current,
 395               dnl age, revision, installed, dlopen, dlpreopen, libdir.
 396               save_libdir="$libdir"
 397               case "$found_la" in
 398                 */* | *\\*) . "$found_la" ;;
 399                 *) . "./$found_la" ;;
 400               esac
 401               libdir="$save_libdir"
 402               dnl We use only dependency_libs.
 403               for dep in $dependency_libs; do
 404                 case "$dep" in
 405                   -L*)
 406                     additional_libdir=`echo "X$dep" | sed -e 's/^X-L//'`
 407                     dnl Potentially add $additional_libdir to $LIBNAME and $LTLIBNAME.
 408                     dnl But don't add it
 409                     dnl   1. if it's the standard /usr/lib,
 410                     dnl   2. if it's /usr/local/lib and we are using GCC on Linux,
 411                     dnl   3. if it's already present in $LDFLAGS or the already
 412                     dnl      constructed $LIBNAME,
 413                     dnl   4. if it doesn't exist as a directory.
 414                     if test "X$additional_libdir" != "X/usr/$acl_libdirstem"; then
 415                       haveit=
 416                       if test "X$additional_libdir" = "X/usr/local/$acl_libdirstem"; then
 417                         if test -n "$GCC"; then
 418                           case $host_os in
 419                             linux* | gnu* | k*bsd*-gnu) haveit=yes;;
 420                           esac
 421                         fi
 422                       fi
 423                       if test -z "$haveit"; then
 424                         haveit=
 425                         for x in $LDFLAGS $LIB[]NAME; do
 426                           AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
 427                           if test "X$x" = "X-L$additional_libdir"; then
 428                             haveit=yes
 429                             break
 430                           fi
 431                         done
 432                         if test -z "$haveit"; then
 433                           if test -d "$additional_libdir"; then
 434                             dnl Really add $additional_libdir to $LIBNAME.
 435                             LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-L$additional_libdir"
 436                           fi
 437                         fi
 438                         haveit=
 439                         for x in $LDFLAGS $LTLIB[]NAME; do
 440                           AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
 441                           if test "X$x" = "X-L$additional_libdir"; then
 442                             haveit=yes
 443                             break
 444                           fi
 445                         done
 446                         if test -z "$haveit"; then
 447                           if test -d "$additional_libdir"; then
 448                             dnl Really add $additional_libdir to $LTLIBNAME.
 449                             LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-L$additional_libdir"
 450                           fi
 451                         fi
 452                       fi
 453                     fi
 454                     ;;
 455                   -R*)
 456                     dir=`echo "X$dep" | sed -e 's/^X-R//'`
 457                     if test "$enable_rpath" != no; then
 458                       dnl Potentially add DIR to rpathdirs.
 459                       dnl The rpathdirs will be appended to $LIBNAME at the end.
 460                       haveit=
 461                       for x in $rpathdirs; do
 462                         if test "X$x" = "X$dir"; then
 463                           haveit=yes
 464                           break
 465                         fi
 466                       done
 467                       if test -z "$haveit"; then
 468                         rpathdirs="$rpathdirs $dir"
 469                       fi
 470                       dnl Potentially add DIR to ltrpathdirs.
 471                       dnl The ltrpathdirs will be appended to $LTLIBNAME at the end.
 472                       haveit=
 473                       for x in $ltrpathdirs; do
 474                         if test "X$x" = "X$dir"; then
 475                           haveit=yes
 476                           break
 477                         fi
 478                       done
 479                       if test -z "$haveit"; then
 480                         ltrpathdirs="$ltrpathdirs $dir"
 481                       fi
 482                     fi
 483                     ;;
 484                   -l*)
 485                     dnl Handle this in the next round.
 486                     names_next_round="$names_next_round "`echo "X$dep" | sed -e 's/^X-l//'`
 487                     ;;
 488                   *.la)
 489                     dnl Handle this in the next round. Throw away the .la's
 490                     dnl directory; it is already contained in a preceding -L
 491                     dnl option.
 492                     names_next_round="$names_next_round "`echo "X$dep" | sed -e 's,^X.*/,,' -e 's,^lib,,' -e 's,\.la$,,'`
 493                     ;;
 494                   *)
 495                     dnl Most likely an immediate library name.
 496                     LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$dep"
 497                     LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }$dep"
 498                     ;;
 499                 esac
 500               done
 501             fi
 502           else
 503             dnl Didn't find the library; assume it is in the system directories
 504             dnl known to the linker and runtime loader. (All the system
 505             dnl directories known to the linker should also be known to the
 506             dnl runtime loader, otherwise the system is severely misconfigured.)
 507             LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }-l$name"
 508             LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-l$name"
 509           fi
 510         fi
 511       fi
 512     done
 513   done
 514   if test "X$rpathdirs" != "X"; then
 515     if test -n "$hardcode_libdir_separator"; then
 516       dnl Weird platform: only the last -rpath option counts, the user must
 517       dnl pass all path elements in one option. We can arrange that for a
 518       dnl single library, but not when more than one $LIBNAMEs are used.
 519       alldirs=
 520       for found_dir in $rpathdirs; do
 521         alldirs="${alldirs}${alldirs:+$hardcode_libdir_separator}$found_dir"
 522       done
 523       dnl Note: hardcode_libdir_flag_spec uses $libdir and $wl.
 524       acl_save_libdir="$libdir"
 525       libdir="$alldirs"
 526       eval flag=\"$hardcode_libdir_flag_spec\"
 527       libdir="$acl_save_libdir"
 528       LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
 529     else
 530       dnl The -rpath options are cumulative.
 531       for found_dir in $rpathdirs; do
 532         acl_save_libdir="$libdir"
 533         libdir="$found_dir"
 534         eval flag=\"$hardcode_libdir_flag_spec\"
 535         libdir="$acl_save_libdir"
 536         LIB[]NAME="${LIB[]NAME}${LIB[]NAME:+ }$flag"
 537       done
 538     fi
 539   fi
 540   if test "X$ltrpathdirs" != "X"; then
 541     dnl When using libtool, the option that works for both libraries and
 542     dnl executables is -R. The -R options are cumulative.
 543     for found_dir in $ltrpathdirs; do
 544       LTLIB[]NAME="${LTLIB[]NAME}${LTLIB[]NAME:+ }-R$found_dir"
 545     done
 546   fi
 547 ])
 548
 549 dnl AC_LIB_APPENDTOVAR(VAR, CONTENTS) appends the elements of CONTENTS to VAR,
 550 dnl unless already present in VAR.
 551 dnl Works only for CPPFLAGS, not for LIB* variables because that sometimes
 552 dnl contains two or three consecutive elements that belong together.
 553 AC_DEFUN([AC_LIB_APPENDTOVAR],
 554 [
 555   for element in [$2]; do
 556     haveit=
 557     for x in $[$1]; do
 558       AC_LIB_WITH_FINAL_PREFIX([eval x=\"$x\"])
 559       if test "X$x" = "X$element"; then
 560         haveit=yes
 561         break
 562       fi
 563     done
 564     if test -z "$haveit"; then
 565       [$1]="${[$1]}${[$1]:+ }$element"
 566     fi
 567   done
 568 ])
 569
 570 dnl For those cases where a variable contains several -L and -l options
 571 dnl referring to unknown libraries and directories, this macro determines the
 572 dnl necessary additional linker options for the runtime path.
 573 dnl AC_LIB_LINKFLAGS_FROM_LIBS([LDADDVAR], [LIBSVALUE], [USE-LIBTOOL])
 574 dnl sets LDADDVAR to linker options needed together with LIBSVALUE.
 575 dnl If USE-LIBTOOL evaluates to non-empty, linking with libtool is assumed,
 576 dnl otherwise linking without libtool is assumed.
 577 AC_DEFUN([AC_LIB_LINKFLAGS_FROM_LIBS],
 578 [
 579   AC_REQUIRE([AC_LIB_RPATH])
 580   AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
 581   $1=
 582   if test "$enable_rpath" != no; then
 583     if test -n "$hardcode_libdir_flag_spec" && test "$hardcode_minus_L" = no; then
 584       dnl Use an explicit option to hardcode directories into the resulting
 585       dnl binary.
 586       rpathdirs=
 587       next=
 588       for opt in $2; do
 589         if test -n "$next"; then
 590           dir="$next"
 591           dnl No need to hardcode the standard /usr/lib.
 592           if test "X$dir" != "X/usr/$acl_libdirstem"; then
 593             rpathdirs="$rpathdirs $dir"
 594           fi
 595           next=
 596         else
 597           case $opt in
 598             -L) next=yes ;;
 599             -L*) dir=`echo "X$opt" | sed -e 's,^X-L,,'`
 600                  dnl No need to hardcode the standard /usr/lib.
 601                  if test "X$dir" != "X/usr/$acl_libdirstem"; then
 602                    rpathdirs="$rpathdirs $dir"
 603                  fi
 604                  next= ;;
 605             *) next= ;;
 606           esac
 607         fi
 608       done
 609       if test "X$rpathdirs" != "X"; then
 610         if test -n ""$3""; then
 611           dnl libtool is used for linking. Use -R options.
 612           for dir in $rpathdirs; do
 613             $1="${$1}${$1:+ }-R$dir"
 614           done
 615         else
 616           dnl The linker is used for linking directly.
 617           if test -n "$hardcode_libdir_separator"; then
 618             dnl Weird platform: only the last -rpath option counts, the user
 619             dnl must pass all path elements in one option.
 620             alldirs=
 621             for dir in $rpathdirs; do
 622               alldirs="${alldirs}${alldirs:+$hardcode_libdir_separator}$dir"
 623             done
 624             acl_save_libdir="$libdir"
 625             libdir="$alldirs"
 626             eval flag=\"$hardcode_libdir_flag_spec\"
 627             libdir="$acl_save_libdir"
 628             $1="$flag"
 629           else
 630             dnl The -rpath options are cumulative.
 631             for dir in $rpathdirs; do
 632               acl_save_libdir="$libdir"
 633               libdir="$dir"
 634               eval flag=\"$hardcode_libdir_flag_spec\"
 635               libdir="$acl_save_libdir"
 636               $1="${$1}${$1:+ }$flag"
 637             done
 638           fi
 639         fi
 640       fi
 641     fi
 642   fi
 643   AC_SUBST([$1])
 644 ])