X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=docs%2FHowToSetUpLLVMStyleRTTI.rst;h=38929948590916ecc1198980e012abe21631295e;hp=c293b4e40692bb47825ecbff64bdfefca80d7ca5;hb=5ad5d2c5359a4e878c732db59ee7fc6e0a25dc00;hpb=a5f199122af73034160ee9ce423931adc8035cf4

diff --git a/docs/HowToSetUpLLVMStyleRTTI.rst b/docs/HowToSetUpLLVMStyleRTTI.rst
index c293b4e4069..38929948590 100644
--- a/docs/HowToSetUpLLVMStyleRTTI.rst
+++ b/docs/HowToSetUpLLVMStyleRTTI.rst
@@ -377,6 +377,20 @@ contract for ``classof`` is "return ``true`` if the dynamic type of the
 argument is-a ``C``".  As long as your implementation fulfills this
 contract, you can tweak and optimize it as much as you want.
 
+For example, LLVM-style RTTI can work fine in the presence of
+multiple-inheritance by defining an appropriate ``classof``.
+An example of this in practice is
+`Decl <http://clang.llvm.org/doxygen/classclang_1_1Decl.html>`_ vs.
+`DeclContext <http://clang.llvm.org/doxygen/classclang_1_1DeclContext.html>`_
+inside Clang.
+The ``Decl`` hierarchy is done very similarly to the example setup
+demonstrated in this tutorial.
+The key part is how to then incorporate ``DeclContext``: all that is needed
+is in ``bool DeclContext::classof(const Decl *)``, which asks the question
+"Given a ``Decl``, how can I determine if it is-a ``DeclContext``?".
+It answers this with a simple switch over the set of ``Decl`` "kinds", and
+returning true for ones that are known to be ``DeclContext``'s.
+
 .. TODO::
 
    Touch on some of the more advanced features, like ``isa_impl`` and