Force recompilation of BCOs when they were compiled in HscNothing mode.

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

diff --git a/compiler/main/HscTypes.lhs b/compiler/main/HscTypes.lhs
index 03bcca5..1d3f4dc 100644 (file)
--- a/compiler/main/HscTypes.lhs
+++ b/compiler/main/HscTypes.lhs
@@ -15,9 +15,10 @@ module HscTypes (
         SourceError, GhcApiError, mkSrcErr, srcErrorMessages, mkApiErr,
         throwOneError, handleSourceError,
         reflectGhc, reifyGhc,
+        handleFlagWarnings,
 
        -- * Sessions and compilation state
-       Session(..), withSession, modifySession,
+       Session(..), withSession, modifySession, withTempSession,
         HscEnv(..), hscEPS,
        FinderCache, FindResult(..), ModLocationCache,
        Target(..), TargetId(..), pprTarget, pprTargetId,
@@ -131,7 +132,8 @@ import TyCon
 import DataCon         ( DataCon, dataConImplicitIds, dataConWrapId )
 import PrelNames       ( gHC_PRIM )
 import Packages hiding ( Version(..) )
-import DynFlags                ( DynFlags(..), isOneShot, HscTarget (..) )
+import DynFlags                ( DynFlags(..), isOneShot, HscTarget (..), dopt,
+                          DynFlag(..) )
 import DriverPhases    ( HscSource(..), isHsBoot, hscSourceString, Phase )
 import BasicTypes      ( IPName, Fixity, defaultFixity, WarningTxt(..) )
 import OptimizationFuel        ( OptFuelState )
@@ -141,7 +143,7 @@ import CoreSyn              ( CoreRule )
 import Maybes          ( orElse, expectJust, catMaybes )
 import Outputable
 import BreakArray
-import SrcLoc          ( SrcSpan, Located )
+import SrcLoc          ( SrcSpan, Located(..) )
 import LazyUniqFM              ( lookupUFM, eltsUFM, emptyUFM )
 import UniqSupply      ( UniqSupply )
 import FastString
@@ -158,7 +160,7 @@ import System.Time  ( ClockTime )
 import Data.IORef
 import Data.Array       ( Array, array )
 import Data.List
-import Control.Monad    ( mplus, guard, liftM )
+import Control.Monad    ( mplus, guard, liftM, when )
 import Exception
 \end{code}
 
@@ -291,6 +293,16 @@ modifySession :: GhcMonad m => (HscEnv -> HscEnv) -> m ()
 modifySession f = do h <- getSession
                      setSession $! f h
 
+withSavedSession :: GhcMonad m => m a -> m a
+withSavedSession m = do
+  saved_session <- getSession
+  m `gfinally` setSession saved_session
+
+-- | Call an action with a temporarily modified Session.
+withTempSession :: GhcMonad m => (HscEnv -> HscEnv) -> m a -> m a
+withTempSession f m =
+  withSavedSession $ modifySession f >> m
+
 -- | A minimal implementation of a 'GhcMonad'.  If you need a custom monad,
 -- e.g., to maintain additional state consider wrapping this monad or using
 -- 'GhcT'.
@@ -409,6 +421,24 @@ reflectGhc m = unGhc m
 -- > Dual to 'reflectGhc'.  See its documentation.
 reifyGhc :: (Session -> IO a) -> Ghc a
 reifyGhc act = Ghc $ act
+
+handleFlagWarnings :: GhcMonad m => DynFlags -> [Located String] -> m ()
+handleFlagWarnings dflags warns
+ = when (dopt Opt_WarnDeprecatedFlags dflags)
+        (handleFlagWarnings' dflags warns)
+
+handleFlagWarnings' :: GhcMonad m => DynFlags -> [Located String] -> m ()
+handleFlagWarnings' _ [] = return ()
+handleFlagWarnings' dflags warns
+ = do -- It would be nicer if warns :: [Located Message], but that has circular
+      -- import problems.
+      logWarnings $ listToBag (map mkFlagWarning warns)
+      when (dopt Opt_WarnIsError dflags) $
+        liftIO $ throwIO $ mkSrcErr emptyBag
+
+mkFlagWarning :: Located String -> WarnMsg
+mkFlagWarning (L loc warn)
+ = mkPlainWarnMsg loc (text warn)
 \end{code}
 
 \begin{code}
@@ -1344,7 +1374,7 @@ lookupType dflags hpt pte name
 lookupTypeHscEnv :: HscEnv -> Name -> IO (Maybe TyThing)
 lookupTypeHscEnv hsc_env name = do
     eps <- readIORef (hsc_EPS hsc_env)
-    return $ lookupType dflags hpt (eps_PTE eps) name
+    return $! lookupType dflags hpt (eps_PTE eps) name
   where 
     dflags = hsc_dflags hsc_env
     hpt = hsc_HPT hsc_env
@@ -1962,8 +1992,14 @@ data Linkable = LM {
                                        -- (i.e. when the bytecodes were produced,
                                        --       or the mod date on the files)
   linkableModule   :: Module,           -- ^ The linkable module itself
-  linkableUnlinked :: [Unlinked]        -- ^ Those files and chunks of code we have
-                                        -- yet to link
+  linkableUnlinked :: [Unlinked]
+    -- ^ Those files and chunks of code we have yet to link.
+    --
+    -- INVARIANT: A valid linkable always has at least one 'Unlinked' item.
+    -- If this list is empty, the Linkable represents a fake linkable, which
+    -- is generated in HscNothing mode to avoid recompiling modules.
+    --
+    -- XXX: Do items get removed from this list when they get linked?
  }
 
 isObjectLinkable :: Linkable -> Bool