[project @ 2000-07-03 21:31:28 by panne]

[ghc-hetmet.git] / ghc / compiler / main / MkIface.lhs

diff --git a/ghc/compiler/main/MkIface.lhs b/ghc/compiler/main/MkIface.lhs
index fbca8ce..354b7da 100644 (file)
--- a/ghc/compiler/main/MkIface.lhs
+++ b/ghc/compiler/main/MkIface.lhs
@@ -68,6 +68,7 @@ import Bag
 import Outputable
 
 import Maybe           ( isNothing )
+import Monad           ( when )
 \end{code}
 
 
@@ -99,17 +100,16 @@ writeIface this_mod old_iface new_iface
     in
 
     case checkIface old_iface full_new_iface of {
-       Nothing -> do { putStrLn "Interface file unchanged" ;
-                       return () } ;   -- No need to update .hi file
+       Nothing -> when opt_D_dump_rn_trace $
+                       putStrLn "Interface file unchanged" ;  -- No need to update .hi file
 
        Just final_iface ->
 
     do  let mod_vers_unchanged = case old_iface of
                                   Just iface -> pi_vers iface == pi_vers final_iface
                                   Nothing -> False
-       if mod_vers_unchanged 
-          then putStrLn "Module version unchanged, but usages differ; hence need new hi file"
-          else return ()
+       when (mod_vers_unchanged && opt_D_dump_rn_trace) $
+            putStrLn "Module version unchanged, but usages differ; hence need new hi file"
 
        if_hdl <- openFile filename WriteMode
        printForIface if_hdl (pprIface final_iface)