[project @ 2002-03-12 10:41:48 by simonmar]

When deciding whether the source for a module is unchanged, don't look
at the file referred to in the argument of '-o' unless it really is
the object file for this compilation (it might be the binary instead).

MERGE TO STABLE

diff --git a/ghc/compiler/main/DriverPipeline.hs b/ghc/compiler/main/DriverPipeline.hs
index ec45002..fb98729 100644 (file)
--- a/ghc/compiler/main/DriverPipeline.hs
+++ b/ghc/compiler/main/DriverPipeline.hs
@@ -529,10 +529,13 @@ run_phase Hsc basename suff input_fn output_fn
        do_recomp   <- readIORef v_Recomp
        todo        <- readIORef v_GhcMode
        expl_o_file <- readIORef v_Output_file
-        let o_file = 
-               case expl_o_file of
-                 Nothing -> unJust "source_unchanged" (ml_obj_file location)
-                 Just x  -> x
+
+       let o_file -- if the -o option is given and IT IS THE OBJECT FILE FOR
+                  -- THIS COMPILATION, then use that to determine if the 
+                  -- source is unchanged.
+               | Just x <- expl_o_file, todo == StopBefore Ln  =  x
+               | otherwise = unJust "source_unchanged" (ml_obj_file location)
+
        source_unchanged <- 
           if not (do_recomp && ( todo == DoLink || todo == StopBefore Ln ))
             then return False