Rationalise GhcMode, HscTarget and GhcLink

[ghc-hetmet.git] / compiler / main / Main.hs

diff --git a/compiler/main/Main.hs b/compiler/main/Main.hs
index 09d8185..048eee8 100644 (file)
--- a/compiler/main/Main.hs
+++ b/compiler/main/Main.hs
@@ -13,7 +13,8 @@ module Main (main) where
 
 -- The official GHC API
 import qualified GHC
-import GHC             ( Session, DynFlags(..), GhcMode(..), HscTarget(..),
+import GHC             ( Session, DynFlags(..), HscTarget(..), 
+                          GhcMode(..), GhcLink(..),
                          LoadHowMuch(..), dopt, DynFlag(..) )
 import CmdLineParser
 
@@ -78,29 +79,39 @@ main =
   -- 2. Parse the "mode" flags (--make, --interactive etc.)
   (cli_mode, argv3) <- parseModeFlags argv2
 
-  let mode = case cli_mode of
-               DoInteractive   -> Interactive
-               DoEval _        -> Interactive
-               DoMake          -> BatchCompile
-               DoMkDependHS    -> MkDepend
-               _               -> OneShot
+  -- If all we want to do is to show the version number then do it
+  -- now, before we start a GHC session etc.
+  -- If we do it later then bootstrapping gets confused as it tries
+  -- to find out what version of GHC it's using before package.conf
+  -- exists, so starting the session fails.
+  case cli_mode of
+    ShowVersion     -> do showVersion
+                          exitWith ExitSuccess
+    ShowNumVersion  -> do putStrLn cProjectVersion
+                          exitWith ExitSuccess
+    _               -> return ()
 
   -- start our GHC session
-  session <- GHC.newSession mode mbMinusB
+  session <- GHC.newSession mbMinusB
 
   dflags0 <- GHC.getSessionDynFlags session
 
-  -- set the default HscTarget.  The HscTarget can be further
-  -- adjusted on a module by module basis, using only the -fvia-C and
-  -- -fasm flags.  If the default HscTarget is not HscC or HscAsm,
-  -- -fvia-C and -fasm have no effect.
-  let lang = case cli_mode of 
-                DoInteractive  -> HscInterpreted
-                DoEval _       -> HscInterpreted
-                _other         -> hscTarget dflags0
-
-  let dflags1 = dflags0{ ghcMode = mode,
-                        hscTarget  = lang,
+  -- set the default GhcMode, HscTarget and GhcLink.  The HscTarget
+  -- can be further adjusted on a module by module basis, using only
+  -- the -fvia-C and -fasm flags.  If the default HscTarget is not
+  -- HscC or HscAsm, -fvia-C and -fasm have no effect.
+  let dflt_target = hscTarget dflags0
+      (mode, lang, link)
+         = case cli_mode of
+               DoInteractive   -> (CompManager, HscInterpreted, LinkInMemory)
+               DoEval _        -> (CompManager, HscInterpreted, LinkInMemory)
+               DoMake          -> (CompManager, dflt_target,    LinkBinary)
+               DoMkDependHS    -> (MkDepend,    dflt_target,    LinkBinary)
+               _               -> (OneShot,     dflt_target,    LinkBinary)
+
+  let dflags1 = dflags0{ ghcMode   = mode,
+                        hscTarget = lang,
+                         ghcLink   = link,
                         -- leave out hscOutName for now
                         hscOutName = panic "Main.main:hscOutName not set",
                         verbosity = case cli_mode of
@@ -145,16 +156,16 @@ main =
 
        ---------------- Do the business -----------
   case cli_mode of
-       ShowUsage       -> showGhcUsage dflags cli_mode
-       PrintLibdir     -> putStrLn (topDir dflags)
-       ShowVersion     -> showVersion
-        ShowNumVersion  -> putStrLn cProjectVersion
-        ShowInterface f -> doShowIface dflags f
-       DoMake          -> doMake session srcs
-       DoMkDependHS    -> doMkDependHS session (map fst srcs)
-       StopBefore p    -> oneShot dflags p srcs
-       DoInteractive   -> interactiveUI session srcs Nothing
-       DoEval expr     -> interactiveUI session srcs (Just expr)
+    ShowUsage       -> showGhcUsage dflags cli_mode
+    PrintLibdir     -> putStrLn (topDir dflags)
+    ShowVersion     -> panic "ShowVersion should already have been handled"
+    ShowNumVersion  -> panic "ShowNumVersion should already have been handled"
+    ShowInterface f -> doShowIface dflags f
+    DoMake          -> doMake session srcs
+    DoMkDependHS    -> doMkDependHS session (map fst srcs)
+    StopBefore p    -> oneShot dflags p srcs
+    DoInteractive   -> interactiveUI session srcs Nothing
+    DoEval expr     -> interactiveUI session srcs (Just expr)
 
   dumpFinalStats dflags
   exitWith ExitSuccess