diff --git a/distrib/compare/Utils.hs b/distrib/compare/Utils.hs
index 720f533aaaced9d062f43b064e66d4559fed9ac7..bc4fd204fd3a78b01d9ad84ca2b47508cccfb6ec 100644
--- a/distrib/compare/Utils.hs
+++ b/distrib/compare/Utils.hs
@@ -11,11 +11,15 @@ die :: Errors -> IO a
 die errs = do mapM_ (hPutStrLn stderr) errs
               exitFailure
 
+warn :: Errors -> IO ()
+warn warnings = mapM_ (hPutStrLn stderr) warnings
+
 dieOnErrors :: Either Errors a -> IO a
 dieOnErrors (Left errs) = die errs
 dieOnErrors (Right x) = return x
 
 type Errors = [String]
+type Warnings = [String]
 
 maybeRead :: Read a => String -> Maybe a
 maybeRead str = case reads str of
diff --git a/distrib/compare/compare.hs b/distrib/compare/compare.hs
index 23b983f0ac77efdb73b5495add6737d3784bb0ec..81055c2826d95d7c33deef5060341b234e5348d5 100644
--- a/distrib/compare/compare.hs
+++ b/distrib/compare/compare.hs
@@ -52,7 +52,8 @@ doDirectory ignoreSizeChanges p1 p2
           mkFileInfo fp@('g':'h':'c':'-':x:xs)
            | isDigit x = return [(("ghc-", "VERSION", dropWhile isVersionChar xs), fp)]
            | otherwise = die ["No version number in " ++ show fp]
-          mkFileInfo fp = die ["Unrecognised filename " ++ show fp]
+          mkFileInfo fp = do warn ["Unrecognised filename " ++ show fp]
+                             return []
       fss1' <- mapM mkFileInfo fs1
       fss2' <- mapM mkFileInfo fs2
       let fs1' = sort $ concat fss1'