updated:
Today, I have tried the method listed in
http://clang.llvm.org/get_started.htmlto build a clang.exe, but no luck, all failed

.
1, one failed method.
under Msys mingw, check out the llvm and clang svn code, and configure. make. but the error occurred when I run the make, such as:
$ make
Makefile:130: /Makefile.rules: No such file or directory
make: *** No rule to make target `/Makefile.rules'. Stop.
2. failed method two:
I just use the cmake, then generate the makefile for mingw, then just run the make command.
when at build stage 97%, I get these message:
Linking CXX executable ..\..\..\..\bin\c-index-test.exe
CMakeFiles\c-index-test.dir\c-index-test.c.obj:c-index-test.c:(.text+0x47a4): un
defined reference to `_imp__pthread_create'
CMakeFiles\c-index-test.dir\c-index-test.c.obj:c-index-test.c:(.text+0x47e0): un
defined reference to `_imp__pthread_join'
collect2: ld returned 1 exit status
make[2]: *** [bin/c-index-test.exe] Error 1
make[1]: *** [tools/clang/tools/c-index-test/CMakeFiles/c-index-test.dir/all] Er
ror 2
make: *** [all] Error 2
E:\clang_build\build\tools\clang>
I have struggleed with the pthread for several hour,( copy some libs or shared libs...), and finally I still get stuck.
I hope some brave guy can help to build a clang distribution (windows). thanks.currently, I can't find any clang binaries for windows.
thanks.