Why? This is a FreeBSD 9.0 system and I get the src directory with csup. I think it should work. It looks that some header files are missing.
Code:
PC-686# make buildworld
--------------------------------------------------------------
>>> World build started on Fri Mar 23 00:00:32 CST 2012
--------------------------------------------------------------
--------------------------------------------------------------
>>> Rebuilding the temporary build tree
--------------------------------------------------------------
rm -rf /usr/obj/usr/src/tmp
rm -rf /usr/obj/usr/src/lib32
mkdir -p /usr/obj/usr/src/tmp/lib
mkdir -p /usr/obj/usr/src/tmp/usr
mkdir -p /usr/obj/usr/src/tmp/legacy/usr
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Host.cpp:14:31: error: llvm/Support/Host.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Host.cpp:15:32: error: llvm/Config/config.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/IntervalMap.cpp:14:34: error: llvm/ADT/IntervalMap.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/IntEqClasses.cpp:21:35: error: llvm/ADT/IntEqClasses.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/ManagedStatic.cpp:14:40: error: llvm/Support/ManagedStatic.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/ManagedStatic.cpp:15:32: error: llvm/Config/config.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/ManagedStatic.cpp:16:33: error: llvm/Support/Atomic.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Memory.cpp:15:33: error: llvm/Support/Memory.h: No such file or directory
/PathV2.cpp:14:33: error: llvm/Support/PathV2.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/PathV2.cpp:15:37: error: llvm/Support/FileSystem.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/PathV2.cpp:16:40: error: llvm/Support/ErrorHandling.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/PluginLoader.cpp:15:40: error: llvm/Support/ManagedStatic.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/PluginLoader.cpp:19:32: error: llvm/Support/Mutex.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/PrettyStackTrace.cpp:15:75: error: llvm/Config/config.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/PrettyStackTrace.cpp:16:43: error: llvm/Support/raw_ostream.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Statistic.cpp:29:32: error: llvm/Support/Mutex.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Statistic.cpp:30:35: error: llvm/ADT/StringExtras.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringExtras.cpp:14:34: error: llvm/ADT/SmallVector.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringExtras.cpp:15:32: error: llvm/ADT/STLExtras.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringExtras.cpp:16:35: error: llvm/ADT/StringExtras.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringMap.cpp:14:32: error: llvm/ADT/StringMap.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringMap.cpp:15:35: error: llvm/ADT/StringExtras.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringPool.cpp:14:37: error: llvm/Support/StringPool.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringPool.cpp:15:32: error: llvm/ADT/StringRef.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringRef.cpp:10:32: error: llvm/ADT/StringRef.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringRef.cpp:11:28: error: llvm/ADT/APInt.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/StringRef.cpp:12:32: error: llvm/ADT/OwningPtr.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/TargetRegistry.cpp:10:41: error: llvm/Support/TargetRegistry.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/TargetRegistry.cpp:11:32: error: llvm/ADT/STLExtras.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/TargetRegistry.cpp:12:32: error: llvm/ADT/StringRef.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/TargetRegistry.cpp:13:31: error: llvm/Support/Host.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/TargetRegistry.cpp:14:38: error: llvm/Support/raw_ostream.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/ThreadLocal.cpp:14:32: error: llvm/Config/config.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/ThreadLocal.cpp:15:38: error: llvm/Support/ThreadLocal.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Threading.cpp:14:36: error: /StringMap.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/ToolOutputFile.cpp:14:41: error: llvm/Support/ToolOutputFile.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/ToolOutputFile.cpp:15:34: error: llvm/Support/Signals.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Triple.cpp:10:29: error: llvm/ADT/Triple.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Triple.cpp:11:34: error: llvm/ADT/SmallString.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Triple.cpp:12:32: error: llvm/ADT/STLExtras.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Twine.cpp:10:28: error: llvm/ADT/Twine.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Twine.cpp:11:34: error: llvm/ADT/SmallString.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Twine.cpp:12:32: error: llvm/Support/Debug.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Twine.cpp:13:38: error: llvm/Support/raw_ostream.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Valgrind.cpp:16:35: error: llvm/Support/Valgrind.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/Valgrind.cpp:17:32: error: llvm/Config/config.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/circular_raw_ostream.cpp:14:47: error: llvm/Support/circular_raw_ostream.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_os_ostream.cpp:14:41: error: llvm/Support/raw_os_ostream.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:14:38: error: llvm/Support/raw_ostream.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:15:33: error: llvm/Support/Format.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:16:34: error: llvm/Support/Program.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:17:34: error: llvm/Support/Process.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:18:35: error: llvm/ADT/StringExtras.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:19:34: error: llvm/ADT/SmallVector.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:20:32: error: llvm/Config/config.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:21:35: error: llvm/Support/Compiler.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:22:40: error: llvm/Support/ErrorHandling.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/raw_ostream.cpp:23:32: error: llvm/ADT/STLExtras.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/system_error.cpp:14:39: error: llvm/Support/system_error.h: No such file or directory
/usr/src/lib/clang/libllvmsupport/../../../contrib/llvm/lib/Support/system_error.cpp:15:32: error: llvm/Support/Errno.h: No such file or directory
mkdep: compile failed
*** Error code 1
Stop in /usr/src/lib/clang/libllvmsupport.
*** Error code 1
Stop in /usr/src.
*** Error code 1
Stop in /usr/src.
*** Error code 1
Stop in /usr/src.