mention the non-standard builtin macros we support.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@68935 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/LanguageExtensions.html b/docs/LanguageExtensions.html
index d298a56..070fdc2 100644
--- a/docs/LanguageExtensions.html
+++ b/docs/LanguageExtensions.html
@@ -19,6 +19,7 @@
 
 <ul>
 <li><a href="#intro">Introduction</a></li>
+<li><a href="#builtinmacros">Builtin Macros</a></li>
 <li><a href="#vectors">Vectors and Extended Vectors</a></li>
 <li><a href="#blocks">Blocks</a></li>
 <li><a href="#overloading-in-c">Function Overloading in C</a></li>
@@ -50,6 +51,12 @@
 more information on these extensions.</p>
 
 <!-- ======================================================================= -->
+<h2 id="builtinmacros">Builtin Macros</h2>
+<!-- ======================================================================= -->
+
+<p>__BASE_FILE__, __INCLUDE_LEVEL__, __TIMESTAMP__, __COUNTER__</p>
+
+<!-- ======================================================================= -->
 <h2 id="vectors">Vectors and Extended Vectors</h2>
 <!-- ======================================================================= -->