LLVM

1、Checkout LLVM:
cd where-you-want-llvm-to-live
svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm


2、Checkout Clang:
cd where-you-want-llvm-to-live
cd llvm/tools
svn co http://llvm.org/svn/llvm-project/cfe/trunk clang


3、Check out extra Clang tools: (optional)
cd llvm/tools/clang/tools
svn co http://llvm.org/svn/llvm-project/clang-tools-extra/trunk extra


4、Checkout Compiler-RT (required to build the sanitizers) [Optional]:
cd llvm/projects
svn co http://llvm.org/svn/llvm-project/compiler-rt/trunk compiler-rt


5、Checkout Libomp (required for OpenMP support) [Optional]:
cd llvm/projects
svn co http://llvm.org/svn/llvm-project/openmp/trunk openmp


6、Checkout libcxx and libcxxabi: (only required to build and run Compiler-RT tests on OS X, optional otherwise)
cd llvm/projects
svn co http://llvm.org/svn/llvm-project/libcxx/trunk libcxx
svn co http://llvm.org/svn/llvm-project/libcxxabi/trunk libcxxabi


7、Get the Test Suite Source Code [Optional]
cd where-you-want-llvm-to-live
cd llvm/projects
svn co http://llvm.org/svn/llvm-project/test-suite/trunk test-suite