Obtaining read only access to the LLDB sources is easy:

• svn co http://llvm.org/svn/llvm-project/lldb/trunk lldb

If you prefer using Git, you can check out LLDB from the LLVM git mirror instead:

• git clone http://llvm.org/git/lldb.git

If you wish to contribute to LLDB, you must first get commit access by requesting commit access

Once you have commit access, you will have a USERNAME and you can checkout the sources: requesting commit access

• svn co https://USERNAME@llvm.org/svn/llvm-project/lldb/trunk lldb