Add a cmake build system.

Will add support for tests with lit in a later patch.
This does not yet support building the unwinder in src/Unwind.


git-svn-id: https://llvm.org/svn/llvm-project/libcxxabi/trunk@212286 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/www/index.html b/www/index.html
index a174afd..e7937fb 100644
--- a/www/index.html
+++ b/www/index.html
@@ -79,6 +79,23 @@
   <li><code>svn co http://llvm.org/svn/llvm-project/libcxxabi/trunk libcxxabi</code></li>
   </ul>
 
+  <p>To build:</p>
+  <ul>
+  <li>Check out libcxxabi into <code>llvm/projects</code></li>
+  <li><code>cd llvm</code></li>
+  <li><code>mkdir build &amp;&amp; cd build</code></li>
+  <li><code>cmake .. # on linux you may need to prefix with CC=clang CXX=clang++</code></li>
+  <li><code>make</code></li>
+  </ul>
+
+  <p>To do a standalone build:</p>
+  <ul>
+  <li><code>cd libcxxabi</code></li>
+  <li><code>mkdir build &amp;&amp; cd build</code></li>
+  <li><code>cmake -DLIBCXXABI_LIBCXX_INCLUDES=path/to/libcxx/include .. # on linux you may need -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++</code></li>
+  <li><code>make</code></li>
+  </ul>
+
   <p>Send discussions to the
   (<a href="http://lists.cs.uiuc.edu/mailman/listinfo/cfe-dev">clang mailing list</a>).</p>