ltconfig

PPP协议的实现演示

# e.g. LANG=C (notably SCO).
if test "X${LC_ALL+set}" = Xset; then LC_ALL=C; export LC_ALL; fi
if test "X${LANG+set}"   = Xset; then LANG=C;   export LANG;   fi

if test -n "$cache_file" && test -r "$cache_file"; then
  echo "loading cache $cache_file within ltconfig"
  . $cache_file
fi

if (echo "testing\c"; echo 1,2,3) | grep c >/dev/null; then
  # Stardent Vistra SVR4 grep lacks -e, says [e-mail].
  if (echo -n testing; echo 1,2,3) | sed s/-n/xn/ | grep xn >/dev/null; then
    ac_n= ac_c='
' ac_t='	'
  else
    ac_n=-n ac_c= ac_t=
  fi
else
  ac_n= ac_c='\c' ac_t=
fi

if test -z "$srcdir"; then
  # Assume the source directory is the same one as the path to LTMAIN.
  srcdir=`$echo "X$ltmain" | $Xsed -e 's%/[^/]*$%%'`
  test "$srcdir" = "$ltmain" && srcdir=.
fi

trap "$rm conftest*; exit 1" 1 2 15
if test "$verify_host" = yes; then
  # Check for config.guess and config.sub.
  ac_aux_dir=
  for ac_dir in $srcdir $srcdir/.. $srcdir/../..; do
    if test -f $ac_dir/config.guess; then
      ac_aux_dir=$ac_dir
      break
    fi
  done
  if test -z "$ac_aux_dir"; then
    echo "$progname: cannot find config.guess in $srcdir $srcdir/.. $srcdir/../.." 1>&2
    echo "$help" 1>&2
    exit 1
  fi
  ac_config_guess=$ac_aux_dir/config.guess
  ac_config_sub=$ac_aux_dir/config.sub

  # Make sure we can run config.sub.
  if $SHELL $ac_config_sub sun4 >/dev/null 2>&1; then :
  else
    echo "$progname: cannot run $ac_config_sub" 1>&2
    echo "$help" 1>&2
    exit 1
  fi

  echo $ac_n "checking host system type""... $ac_c" 1>&6

  host_alias=$host
  case "$host_alias" in
  "")
    if host_alias=`$SHELL $ac_config_guess`; then :
    else
      echo "$progname: cannot guess host type; you must specify one" 1>&2
      echo "$help" 1>&2
      exit 1
    fi ;;
  esac
  host=`$SHELL $ac_config_sub $host_alias`
  echo "$ac_t$host" 1>&6

  # Make sure the host verified.
  test -z "$host" && exit 1

  # Check for the build system type
  echo $ac_n "checking build system type... $ac_c" 1>&6

  build_alias=$build
  case "$build_alias" in
  NONE)
    case $nonopt in
    NONE) build_alias=$host_alias ;;
    *) build_alias=$nonopt ;;
    esac ;;
  esac

  build=`$SHELL $ac_config_sub $build_alias`
  build_cpu=`echo $build | sed 's/^\([^-]*\)-\([^-]*\)-\(.*\)$/\1/'`
  build_vendor=`echo $build | sed 's/^\([^-]*\)-\([^-]*\)-\(.*\)$/\2/'`
  build_os=`echo $build | sed 's/^\([^-]*\)-\([^-]*\)-\(.*\)$/\3/'`
  echo "$ac_t""$build" 1>&6

elif test -z "$host"; then
  echo "$progname: you must specify a host type if you use \`--no-verify'" 1>&2
  echo "$help" 1>&2
  exit 1
else
  host_alias=$host
  build_alias=$host_alias
  build=$host
fi

if test x"$host" != x"$build"; then
  ac_tool_prefix=${host_alias}-
else
  ac_tool_prefix=
fi

host_cpu=`echo $host | sed 's/^\([^-]*\)-\([^-]*\)-\(.*\)$/\1/'`
host_vendor=`echo $host | sed 's/^\([^-]*\)-\([^-]*\)-\(.*\)$/\2/'`
host_os=`echo $host | sed 's/^\([^-]*\)-\([^-]*\)-\(.*\)$/\3/'`

# Transform linux* to *-*-linux-gnu*, to support old configure scripts.
case "$host_os" in
linux-gnu*) ;;
linux*) host=`echo $host | sed 's/^\(.*-.*-linux\)\(.*\)$/\1-gnu\2/'`
esac

case "$host_os" in
aix3*)
  # AIX sometimes has problems with the GCC collect2 program.  For some
  # reason, if we set the COLLECT_NAMES environment variable, the problems
  # vanish in a puff of smoke.
  if test "X${COLLECT_NAMES+set}" != Xset; then
    COLLECT_NAMES=
    export COLLECT_NAMES
  fi
  ;;
esac

# Determine commands to create old-style static archives.
old_archive_cmds='$AR cru $oldlib$oldobjs$old_deplibs'
old_postinstall_cmds='chmod 644 $oldlib'
old_postuninstall_cmds=

# Set sane defaults for various variables
test -z "$AR" && AR=ar
test -z "$AS" && AS=as
test -z "$CC" && CC=cc
test -z "$DLLTOOL" && DLLTOOL=dlltool
test -z "$MAGIC" && MAGIC=file
test -z "$LD" && LD=ld
test -z "$LN_S" && LN_S="ln -s"
test -z "$NM" && NM=nm
test -z "$OBJDUMP" && OBJDUMP=objdump
test -z "$RANLIB" && RANLIB=:
test -z "$STRIP" && STRIP=:
test -z "$objext" && objext=o

echo $ac_n "checking for objdir... $ac_c" 1>&6
rm -f .libs 2>/dev/null
mkdir .libs 2>/dev/null
if test -d .libs; then
  objdir=.libs
else
  # MS-DOS does not allow filenames that begin with a dot.
  objdir=_libs
fi
rmdir .libs 2>/dev/null
echo "$ac_t$objdir" 1>&6

# Allow CC to be a program name with arguments.
set dummy $CC
compiler="$2"

# We assume here that the value for ac_cv_prog_cc_pic will not be cached
# in isolation, and that seeing it set (from the cache) indicates that
# the associated values are set (in the cache) correctly too.
echo $ac_n "checking for $compiler option to produce PIC... $ac_c" 1>&6
echo "$progname:563:checking for $compiler option to produce PIC" 1>&5
if test "X${ac_cv_prog_cc_pic+set}" = Xset; then
  echo $ac_n "(cached) $ac_c" 1>&6
else
  ac_cv_prog_cc_pic=
  ac_cv_prog_cc_shlib=
  ac_cv_prog_cc_wl=
  ac_cv_prog_cc_static=
  ac_cv_prog_cc_no_builtin=
  ac_cv_prog_cc_can_build_shared=$can_build_shared

  if test "$with_gcc" = yes; then
    ac_cv_prog_cc_wl='-Wl,'
    ac_cv_prog_cc_static='-static'

    case "$host_os" in
    beos* | irix5* | irix6* | osf3* | osf4* | osf5*)
      # PIC is the default for these OSes.
      ;;
    aix*)
      # Below there is a dirty hack to force normal static linking with -ldl
      # The problem is because libdl dynamically linked with both libc and
      # libC (AIX C++ library), which obviously doesn't included in libraries
      # list by gcc. This cause undefined symbols with -static flags.
      # This hack allows C programs to be linked with "-static -ldl", but
      # we not sure about C++ programs.
      ac_cv_prog_cc_static="$ac_cv_prog_cc_static ${ac_cv_prog_cc_wl}-lC"
      ;;
    cygwin* | mingw* | os2*)
      # This hack is so that the source file can tell whether it is being
      # built for inclusion in a dll (and should export symbols for example).
      ac_cv_prog_cc_pic='-DDLL_EXPORT'
      ;;
    amigaos*)
      # FIXME: we need at least 68020 code to build shared libraries, but
      # adding the `-m68020' flag to GCC prevents building anything better,
      # like `-m68040'.
      ac_cv_prog_cc_pic='-m68020 -resident32 -malways-restore-a4'
      ;;
    sysv4*MP*)
      if test -d /usr/nec; then
	 ac_cv_prog_cc_pic=-Kconform_pic
      fi
      ;;
    *)
      ac_cv_prog_cc_pic='-fPIC'
      ;;
    esac
  else
    # PORTME Check for PIC flags for the system compiler.
    case "$host_os" in
    aix3* | aix4*)
     # All AIX code is PIC.
      ac_cv_prog_cc_static='-bnso -bI:/lib/syscalls.exp'
      ;;

    hpux9* | hpux10* | hpux11*)
      # Is there a better ac_cv_prog_cc_static that works with the bundled CC?
      ac_cv_prog_cc_wl='-Wl,'
      ac_cv_prog_cc_static="${ac_cv_prog_cc_wl}-a ${ac_cv_prog_cc_wl}archive"
      ac_cv_prog_cc_pic='+Z'
      ;;

    irix5* | irix6*)
      ac_cv_prog_cc_wl='-Wl,'
      ac_cv_prog_cc_static='-non_shared'
      # PIC (with -KPIC) is the default.
      ;;

    cygwin* | mingw* | os2*)
      # This hack is so that the source file can tell whether it is being
      # built for inclusion in a dll (and should export symbols for example).
      ac_cv_prog_cc_pic='-DDLL_EXPORT'
      ;;

    osf3* | osf4* | osf5*)
      # All OSF/1 code is PIC.
      ac_cv_prog_cc_wl='-Wl,'
      ac_cv_prog_cc_static='-non_shared'
      ;;

    sco3.2v5*)
      ac_cv_prog_cc_pic='-Kpic'
      ac_cv_prog_cc_static='-dn'
      ac_cv_prog_cc_shlib='-belf'
      ;;

    solaris*)
      ac_cv_prog_cc_pic='-KPIC'
      ac_cv_prog_cc_static='-Bstatic'
      ac_cv_prog_cc_wl='-Wl,'
      ;;

    sunos4*)
      ac_cv_prog_cc_pic='-PIC'
      ac_cv_prog_cc_static='-Bstatic'
      ac_cv_prog_cc_wl='-Qoption ld '
      ;;

    sysv4 | sysv4.2uw2* | sysv4.3* | sysv5*)
      ac_cv_prog_cc_pic='-KPIC'
      ac_cv_prog_cc_static='-Bstatic'
      ac_cv_prog_cc_wl='-Wl,'
      ;;

    uts4*)
      ac_cv_prog_cc_pic='-pic'
      ac_cv_prog_cc_static='-Bstatic'
      ;;

    sysv4*MP*)
      if test -d /usr/nec ;then
	ac_cv_prog_cc_pic='-Kconform_pic'
	ac_cv_prog_cc_static='-Bstatic'
      fi
      ;;

    *)
      ac_cv_prog_cc_can_build_shared=no
      ;;
    esac
  fi
fi
if test -z "$ac_cv_prog_cc_pic"; then
  echo "$ac_t"none 1>&6
else
  echo "$ac_t""$ac_cv_prog_cc_pic" 1>&6

  # Check to make sure the pic_flag actually works.
  echo $ac_n "checking if $compiler PIC flag $ac_cv_prog_cc_pic works... $ac_c" 1>&6
  echo "$progname:693:checking that $compiler PIC flag $ac_cv_prog_cc_pic works." 1>&5
  if test "X${ac_cv_prog_cc_pic_works+set}" = Xset; then
    echo $ac_n "(cached) $ac_c" 1>&6
  else
    ac_cv_prog_cc_pic_works=yes
    $rm conftest*
    echo "int some_variable = 0;" > conftest.c
    save_CFLAGS="$CFLAGS"
    CFLAGS="$CFLAGS $ac_cv_prog_cc_pic -DPIC"
    if { (eval echo $progname:702: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>conftest.err; } && test -s conftest.$objext; then
      # Append any warnings to the config.log.
      cat conftest.err 1>&5

      case "$host_os" in
      hpux9* | hpux10* | hpux11*)
	# On HP-UX, both CC and GCC only warn that PIC is supported... then
	# they create non-PIC objects.  So, if there were any warnings, we
	# assume that PIC is not supported.
	if test -s conftest.err; then
	  ac_cv_prog_cc_pic_works=no
	  ac_cv_prog_cc_can_build_shared=no
	  ac_cv_prog_cc_pic=
	else
	  ac_cv_prog_cc_pic_works=yes
	  ac_cv_prog_cc_pic=" $ac_cv_prog_cc_pic"
	fi
	;;
      *)
	ac_cv_prog_cc_pic_works=yes
	ac_cv_prog_cc_pic=" $ac_cv_prog_cc_pic"
	;;
      esac
    else
      # Append any errors to the config.log.
      cat conftest.err 1>&5
      ac_cv_prog_cc_pic_works=no
      ac_cv_prog_cc_can_build_shared=no
      ac_cv_prog_cc_pic=
    fi
    CFLAGS="$save_CFLAGS"
    $rm conftest*
  fi
  # Belt *and* braces to stop my trousers falling down:
  if test "X$ac_cv_prog_cc_pic_works" = Xno; then
    ac_cv_prog_cc_pic=
    ac_cv_prog_cc_can_build_shared=no
  fi
  echo "$ac_t""$ac_cv_prog_cc_pic_works" 1>&6
fi

# Check for any special shared library compilation flags.
if test -n "$ac_cv_prog_cc_shlib"; then
  echo "$progname: warning: \`$CC' requires \`$ac_cv_prog_cc_shlib' to build shared libraries" 1>&2
  if echo "$old_CC $old_CFLAGS " | egrep -e "[ 	]$ac_cv_prog_cc_shlib[ 	]" >/dev/null; then :
  else
    echo "$progname: add \`$ac_cv_prog_cc_shlib' to the CC or CFLAGS env variable and reconfigure" 1>&2
    ac_cv_prog_cc_can_build_shared=no
  fi
fi

echo $ac_n "checking if $compiler static flag $ac_cv_prog_cc_static works... $ac_c" 1>&6
echo "$progname:754: checking if $compiler static flag $ac_cv_prog_cc_static works" >&5
if test "X${ac_cv_prog_cc_static_works+set}" = Xset; then
  echo $ac_n "(cached) $ac_c" 1>&6
else
  $rm conftest*
  echo 'main(){return(0);}' > conftest.c
  save_LDFLAGS="$LDFLAGS"
  LDFLAGS="$LDFLAGS $ac_cv_prog_cc_static"
  if { (eval echo $progname:762: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest; then
    ac_cv_prog_cc_static_works=yes
  else
    ac_cv_prog_cc_static_works=no
    ac_cv_prog_cc_static=
  fi
  LDFLAGS="$save_LDFLAGS"
  $rm conftest*
fi
# Belt *and* braces to stop my trousers falling down:
if test "X$ac_cv_prog_cc_static_works" = Xno; then
  ac_cv_prog_cc_static=
fi
echo "$ac_t""$ac_cv_prog_cc_static_works" 1>&6
pic_flag="$ac_cv_prog_cc_pic"
special_shlib_compile_flags="$ac_cv_prog_cc_shlib"
wl="$ac_cv_prog_cc_wl"
link_static_flag="$ac_cv_prog_cc_static"
no_builtin_flag="$ac_cv_prog_cc_no_builtin"
can_build_shared="$ac_cv_prog_cc_can_build_shared"

# Check to see if options -o and -c are simultaneously supported by compiler
echo $ac_n "checking if $compiler supports -c -o file.o... $ac_c" 1>&6
$rm -r conftest 2>/dev/null
mkdir conftest
cd conftest
$rm conftest*
echo "int some_variable = 0;" > conftest.c
mkdir out
# According to Tom Tromey, Ian Lance Taylor reported there are C compilers
# that will create temporary files in the current directory regardless of