diff --git a/clang/lib/Basic/SourceManager.cpp b/clang/lib/Basic/SourceManager.cpp
index 65bd601..eefaacc 100644
--- a/clang/lib/Basic/SourceManager.cpp
+++ b/clang/lib/Basic/SourceManager.cpp
@@ -1577,6 +1577,7 @@
     }      
   }
   
+  (void) SourceFile;
   return FirstFID;
 }