Improve error message from ghc --make when filename and modulename differ

diff --git a/compiler/main/HeaderInfo.hs b/compiler/main/HeaderInfo.hs
index dc1b35c..090af1f 100644 (file)
--- a/compiler/main/HeaderInfo.hs
+++ b/compiler/main/HeaderInfo.hs
@@ -23,7 +23,7 @@ import Module         ( ModuleName, moduleName )
 import PrelNames        ( gHC_PRIM, mAIN_NAME )
 import StringBuffer    ( StringBuffer(..), hGetStringBuffer, hGetStringBufferBlock
                         , appendStringBuffers )
-import SrcLoc          ( Located(..), mkSrcLoc, unLoc, noSrcSpan )
+import SrcLoc
 import FastString      ( mkFastString )
 import DynFlags        ( DynFlags )
 import ErrUtils
@@ -31,6 +31,7 @@ import Util
 import Outputable
 import Pretty           ()
 import Panic
+import Maybes
 import Bag             ( emptyBag, listToBag )
 
 import Distribution.Compiler
@@ -66,17 +67,16 @@ getImports dflags buf filename = do
        PFailed span err -> parseError span err
        POk _ rdr_module -> 
          case rdr_module of
-           L _ (HsModule mod _ imps _ _ _ _ _) ->
+           L _ (HsModule mb_mod _ imps _ _ _ _ _) ->
              let
-               mod_name | Just located_mod <- mod = located_mod
-                        | otherwise               = L noSrcSpan mAIN_NAME
+               mod = mb_mod `orElse` L (srcLocSpan loc) mAIN_NAME
                (src_idecls, ord_idecls) = partition isSourceIdecl (map unLoc imps)
                source_imps   = map getImpMod src_idecls        
                ordinary_imps = filter ((/= moduleName gHC_PRIM) . unLoc) 
                                        (map getImpMod ord_idecls)
                     -- GHC.Prim doesn't exist physically, so don't go looking for it.
              in
-             return (source_imps, ordinary_imps, mod_name)
+             return (source_imps, ordinary_imps, mod)
   
 parseError span err = throwDyn $ mkPlainErrMsg span err