title: Missing libclang_rt.san-x86_64.a file for LLVM compiler-rt
body: <p>I've just built LLVM/Clang <a href="http://compiler-rt.llvm.org/" rel="noreferrer">compiler-rt</a> and tried the <code>-fsanitize</code> option. But strangely the link failed since it cannot find <code>libclang_rt.san-x86_64.a</code>.</p>
  
  <pre><code>/usr/bin/ld: cannot find /home/hongxu/RESEARCH/llvm-git/obj/bin/../lib/clang/3.7.0/lib/linux/libclang_rt.san-x86_64.a: No such file or directory
  clang-3.7: error: linker command failed with exit code 1 (use -v to see invocation)
  </code></pre>
  
  <p>When I changed into directory <code>/home/hongxu/RESEARCH/llvm-git/obj/bin/../lib/clang/3.7.0/lib/linux/</code>, I found that there are other library files</p>
  
  <pre><code># AddressSanitizer
  libclang_rt.asan_cxx-x86_64.a
  libclang_rt.asan-preinit-x86_64.a
  libclang_rt.asan-x86_64.a
  # DataFlowSanitizer
  libclang_rt.dfsan-libc-x86_64.a
  libclang_rt.dfsan-x86_64.a
  # LeakSanitizer
  libclang_rt.lsan-x86_64.a
  # MemorySanitizer
  libclang_rt.msan-x86_64.a
  # ThreadSanitizer
  libclang_rt.tsan-x86_64.a
  # UndefinedBehaviorSanitizer
  libclang_rt.ubsan_cxx-x86_64.a
  libclang_rt.ubsan_standalone_cxx-x86_64.a
  libclang_rt.ubsan_standalone-x86_64.a
  libclang_rt.ubsan-x86_64.a
  </code></pre>
  
  <p>And I can guess their functionalities from the name according to compiler-rt page. </p>
  
  <p>But what is <code>libclang_rt.san-x86_64.a</code>? And how can I get it?</p>