lib-link.m4

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                  -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/$acl_libdirstem"; then
                      haveit=
                      if test "X$additional_libdir" = "X/usr/local/$acl_libdirstem"; then
                        if test -n "$GCC"; then
                          case $host_os in
                            linux* | gnu* | k*bsd*-gnu) haveit=yes;;
                          esac
                        fi
                      fi
                      if test -z "$haveit"; then
                        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$rpathdirs" != "X"; then
    if test -n "$acl_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}${alldirs:+$acl_hardcode_libdir_separator}$found_dir"
      done
      dnl Note: acl_hardcode_libdir_flag_spec uses $libdir and $wl.
      acl_save_libdir="$libdir"
      libdir="$alldirs"
      eval flag=\"$acl_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="$found_dir"
        eval flag=\"$acl_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
  popdef([P_A_C_K])
  popdef([PACKLIBS])
  popdef([PACKUP])
  popdef([PACK])
  popdef([NAME])
])

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
])

dnl For those cases where a variable contains several -L and -l options
dnl referring to unknown libraries and directories, this macro determines the
dnl necessary additional linker options for the runtime path.
dnl AC_LIB_LINKFLAGS_FROM_LIBS([LDADDVAR], [LIBSVALUE], [USE-LIBTOOL])
dnl sets LDADDVAR to linker options needed together with LIBSVALUE.
dnl If USE-LIBTOOL evaluates to non-empty, linking with libtool is assumed,
dnl otherwise linking without libtool is assumed.
AC_DEFUN([AC_LIB_LINKFLAGS_FROM_LIBS],
[
  AC_REQUIRE([AC_LIB_RPATH])
  AC_REQUIRE([AC_LIB_PREPARE_MULTILIB])
  $1=
  if test "$enable_rpath" != no; then
    if test -n "$acl_hardcode_libdir_flag_spec" && test "$acl_hardcode_minus_L" = no; then
      dnl Use an explicit option to hardcode directories into the resulting
      dnl binary.
      rpathdirs=
      next=
      for opt in $2; do
        if test -n "$next"; then
          dir="$next"
          dnl No need to hardcode the standard /usr/lib.
          if test "X$dir" != "X/usr/$acl_libdirstem"; then
            rpathdirs="$rpathdirs $dir"
          fi
          next=
        else
          case $opt in
            -L) next=yes ;;
            -L*) dir=`echo "X$opt" | sed -e 's,^X-L,,'`
                 dnl No need to hardcode the standard /usr/lib.
                 if test "X$dir" != "X/usr/$acl_libdirstem"; then
                   rpathdirs="$rpathdirs $dir"
                 fi
                 next= ;;
            *) next= ;;
          esac
        fi
      done
      if test "X$rpathdirs" != "X"; then
        if test -n ""$3""; then
          dnl libtool is used for linking. Use -R options.
          for dir in $rpathdirs; do
            $1="${$1}${$1:+ }-R$dir"
          done
        else
          dnl The linker is used for linking directly.
          if test -n "$acl_hardcode_libdir_separator"; then
            dnl Weird platform: only the last -rpath option counts, the user
            dnl must pass all path elements in one option.
            alldirs=
            for dir in $rpathdirs; do
              alldirs="${alldirs}${alldirs:+$acl_hardcode_libdir_separator}$dir"
            done
            acl_save_libdir="$libdir"
            libdir="$alldirs"
            eval flag=\"$acl_hardcode_libdir_flag_spec\"
            libdir="$acl_save_libdir"
            $1="$flag"
          else
            dnl The -rpath options are cumulative.
            for dir in $rpathdirs; do
              acl_save_libdir="$libdir"
              libdir="$dir"
              eval flag=\"$acl_hardcode_libdir_flag_spec\"
              libdir="$acl_save_libdir"
              $1="${$1}${$1:+ }$flag"
            done
          fi
        fi
      fi
    fi
  fi
  AC_SUBST([$1])
])