diff --git a/docs/SourceLevelDebugging.html b/docs/SourceLevelDebugging.html
index 789b8ca6490..f1e1cd0285d 100644
--- a/docs/SourceLevelDebugging.html
+++ b/docs/SourceLevelDebugging.html
@@ -744,7 +744,8 @@ DW_TAG_inheritance      = 28
   metadata, ;; Context
   metadata, ;; Name
   metadata, ;; Reference to file where defined
-  i32,      ;; Line number where defined
+  i32,      ;; 24 bit - Line number where defined
+            ;; 8 bit - Argument number. 1 indicates 1st argument.
   metadata  ;; Type descriptor
 }
 </pre>