diff --git a/docs/SourceLevelDebugging.html b/docs/SourceLevelDebugging.html
index c9ae020..4c4439f 100644
--- a/docs/SourceLevelDebugging.html
+++ b/docs/SourceLevelDebugging.html
@@ -342,7 +342,9 @@
    that produced it.</p>
 
 <p>Compile unit descriptors provide the root context for objects declared in a
-   specific compilation unit. File descriptors are defined using this context.</p>
+   specific compilation unit. File descriptors are defined using this context.
+   These descriptors are collected by a named metadata 
+   <tt>!llvm.dbg.cu</tt>.
 
 </div>