[project @ 2004-07-21 09:25:42 by simonpj]

[ghc-hetmet.git] / ghc / compiler / typecheck / TcRnMonad.lhs

diff --git a/ghc/compiler/typecheck/TcRnMonad.lhs b/ghc/compiler/typecheck/TcRnMonad.lhs
index 86af49a..3632acd 100644 (file)
--- a/ghc/compiler/typecheck/TcRnMonad.lhs
+++ b/ghc/compiler/typecheck/TcRnMonad.lhs
@@ -29,7 +29,7 @@ import VarEnv         ( TidyEnv, emptyTidyEnv )
 import ErrUtils                ( Message, Messages, emptyMessages, errorsFound, 
                          mkErrMsg, mkWarnMsg, printErrorsAndWarnings,
                          mkLocMessage, mkLongErrMsg )
-import SrcLoc          ( mkGeneralSrcSpan, SrcSpan, Located(..) )
+import SrcLoc          ( mkGeneralSrcSpan, isGoodSrcSpan, SrcSpan, Located(..) )
 import NameEnv         ( emptyNameEnv )
 import NameSet         ( emptyDUs, emptyNameSet )
 import OccName         ( emptyOccEnv )
@@ -74,6 +74,7 @@ initTc hsc_env mod do_this
        tvs_var      <- newIORef emptyVarSet ;
        type_env_var <- newIORef emptyNameEnv ;
        dfuns_var    <- newIORef emptyNameSet ;
+       th_var       <- newIORef False ;
 
        let {
             gbl_env = TcGblEnv {
@@ -85,6 +86,7 @@ initTc hsc_env mod do_this
                tcg_type_env_var = type_env_var,
                tcg_inst_env  = mkImpInstEnv hsc_env,
                tcg_inst_uses = dfuns_var,
+               tcg_th_used   = th_var,
                tcg_exports  = emptyNameSet,
                tcg_imports  = init_imports,
                tcg_dus      = emptyDUs,
@@ -97,7 +99,7 @@ initTc hsc_env mod do_this
             } ;
             lcl_env = TcLclEnv {
                tcl_errs       = errs_var,
-               tcl_loc        = mkGeneralSrcSpan FSLIT("Top level of module"),
+               tcl_loc        = mkGeneralSrcSpan FSLIT("Top level"),
                tcl_ctxt       = [],
                tcl_rdr        = emptyLocalRdrEnv,
                tcl_th_ctxt    = topStage,
@@ -272,6 +274,10 @@ updateEps_ upd_fn = do     { eps_var <- getEpsVar
 
 getHpt :: TcRnIf gbl lcl HomePackageTable
 getHpt = do { env <- getTopEnv; return (hsc_HPT env) }
+
+getEpsAndHpt :: TcRnIf gbl lcl (ExternalPackageState, HomePackageTable)
+getEpsAndHpt = do { env <- getTopEnv; eps <- readMutVar (hsc_EPS env)
+                 ; return (eps, hsc_HPT env) }
 \end{code}
 
 %************************************************************************
@@ -372,7 +378,9 @@ getSrcSpanM :: TcRn SrcSpan
 getSrcSpanM = do { env <- getLclEnv; return (tcl_loc env) }
 
 addSrcSpan :: SrcSpan -> TcRn a -> TcRn a
-addSrcSpan loc = updLclEnv (\env -> env { tcl_loc = loc })
+addSrcSpan loc thing_inside
+  | isGoodSrcSpan loc = updLclEnv (\env -> env { tcl_loc = loc }) thing_inside
+  | otherwise        = thing_inside    -- Don't overwrite useful info with useless
 
 addLocM :: (a -> TcM b) -> Located a -> TcM b
 addLocM fn (L loc a) = addSrcSpan loc $ fn a
@@ -733,6 +741,9 @@ setLclTypeEnv lcl_env thing_inside
 %************************************************************************
 
 \begin{code}
+recordThUse :: TcM ()
+recordThUse = do { env <- getGblEnv; writeMutVar (tcg_th_used env) True }
+
 getStage :: TcM ThStage
 getStage = do { env <- getLclEnv; return (tcl_th_ctxt env) }