create a build environment for XNU kernel (does not work well)

prepare_for_xnu.sh

#!/bin/sh

#
#  xcodeがなんやかんやなせいなのか、動かなくなっちゃいました（ゝω・）v
#

#
#  Run this shell script on Mac OS X *Lion*.
#  I referred to http://osx86.boeaja.info/2009/10/building-xnu-kernel-on-snow-leopard/
#  You can download XNU kernel source code from http://www.opensource.apple.com/tarballs/xnu/
#

cd /tmp
mkdir prepare_env_for_build_xnu
cd prepare_env_for_build_xnu

#
#  Download tarballs
#

curl -O http://www.opensource.apple.com/tarballs/cxxfilt/cxxfilt-9.tar.gz
curl -O http://www.opensource.apple.com/tarballs/dtrace/dtrace-90.tar.gz
curl -O http://www.opensource.apple.com/tarballs/kext_tools/kext_tools-252.2.tar.gz
curl -O http://www.opensource.apple.com/tarballs/bootstrap_cmds/bootstrap_cmds-80.tar.gz


#
#  Extract tarballs
#

tar xf cxxfilt-9.tar.gz
tar xf dtrace-90.tar.gz
tar xf kext_tools-252.2.tar.gz
tar xf bootstrap_cmds-80.tar.gz


#
#  Build and Install softwares
#

cd cxxfilt-9
mkdir -p obj sym dst
make install RC_ARCHS="i386 x86_64" RC_CFLAGS="-arch i386 -arch x86_64 -pipe" \
             RC_OS=macos RC_RELEASE=Lion SRCROOT=$PWD \
             OBJROOT=$PWD/obj SYMROOT=$PWD/sym DSTROOT=$PWD/dst
sudo ditto $PWD/dst/usr/local /usr/local
cd ..

cd dtrace-90
mkdir -p obj sym dst
xcodebuild install -target ctfconvert -target ctfdump -target ctfmerge \
                   ARCHS="i386 x86_64" \
                   SRCROOT=$PWD OBJROOT=$PWD/obj SYMROOT=$PWD/sym DSTROOT=$PWD/dst
sudo ditto $PWD/dst/usr/local /usr/local
cd ..

cd kext_tools-252.2
mkdir -p obj sym dst
xcodebuild install -target kextsymboltool -target setsegname \
                   ARCHS="i386 x86_64" \
                   SRCROOT=$PWD OBJROOT=$PWD/obj SYMROOT=$PWD/sym DSTROOT=$PWD/dst
sudo ditto $PWD/dst/usr/local /usr/local
cd ..

cd bootstrap_cmds-80
make install RC_ARCHS="i386" RC_CFLAGS="-arch i386 -pipe" RC_OS=macos RC_RELEASE=Lion \
             SRCROOT=$PWD OBJROOT=$PWD/obj SYMROOT=$PWD/sym DSTROOT=$PWD/dst
sudo ditto $PWD/dst/usr/local /usr/local

echo "Done"

Thank you for letting me know.
I'll refer to your comments when I build XNU.

whenever I try to build kextsymboltool, xcode tells me: xcodebuild: error: The project 'kext_tools.xcodeproj' does not contain a target named 'kextsymboltool

@Hnasar I have the same issue. Maybe the official documentation helps you.

Apparently TargetConfig is required too.