[commit: ghc] master: Use lookupIfaceTop for loading IfaceDecls. (dd365b1)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/dd365b1baab08b44e8feb1715ecacf7407628d5c/ghc

>---------------------------------------------------------------

commit dd365b1baab08b44e8feb1715ecacf7407628d5c
Author: Edward Z. Yang <ezyang at cs.stanford.edu>
Date:   Tue Jul 21 17:16:52 2015 -0700

    Use lookupIfaceTop for loading IfaceDecls.
    
    Summary:
    It's shorter!  And then when Backpack overrides lookupIfaceTop
    everyone will see the right information.
    
    Signed-off-by: Edward Z. Yang <ezyang at cs.stanford.edu>
    
    Test Plan: validate
    
    Reviewers: simonpj, austin, bgamari
    
    Subscribers: thomie
    
    Differential Revision: https://phabricator.haskell.org/D1090


>---------------------------------------------------------------

dd365b1baab08b44e8feb1715ecacf7407628d5c
 compiler/iface/IfaceEnv.hs  |  5 ++++-
 compiler/iface/LoadIface.hs | 10 ++++------
 compiler/iface/TcIface.hs   |  4 ++--
 3 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/compiler/iface/IfaceEnv.hs b/compiler/iface/IfaceEnv.hs
index 1bd9316..a822b10 100644
--- a/compiler/iface/IfaceEnv.hs
+++ b/compiler/iface/IfaceEnv.hs
@@ -151,7 +151,10 @@ newImplicitBinder base_name mk_sys_occ
 ifaceExportNames :: [IfaceExport] -> TcRnIf gbl lcl [AvailInfo]
 ifaceExportNames exports = return exports
 
-lookupOrig :: Module -> OccName ->  TcRnIf a b Name
+-- | Look up the 'Name' for a given 'Module' and 'OccName'.
+-- Consider alternately using 'lookupIfaceTop' if you're in the 'IfL' monad
+-- and 'Module' is simply that of the 'ModIface' you are typechecking.
+lookupOrig :: Module -> OccName -> TcRnIf a b Name
 lookupOrig mod occ
   = do  {       -- First ensure that mod and occ are evaluated
                 -- If not, chaos can ensue:
diff --git a/compiler/iface/LoadIface.hs b/compiler/iface/LoadIface.hs
index ad81357..9da1175 100644
--- a/compiler/iface/LoadIface.hs
+++ b/compiler/iface/LoadIface.hs
@@ -585,20 +585,18 @@ loadDecls :: Bool
           -> [(Fingerprint, IfaceDecl)]
           -> IfL [(Name,TyThing)]
 loadDecls ignore_prags ver_decls
-   = do { mod <- getIfModule
-        ; thingss <- mapM (loadDecl ignore_prags mod) ver_decls
+   = do { thingss <- mapM (loadDecl ignore_prags) ver_decls
         ; return (concat thingss)
         }
 
 loadDecl :: Bool                    -- Don't load pragmas into the decl pool
-         -> Module
           -> (Fingerprint, IfaceDecl)
           -> IfL [(Name,TyThing)]   -- The list can be poked eagerly, but the
                                     -- TyThings are forkM'd thunks
-loadDecl ignore_prags mod (_version, decl)
+loadDecl ignore_prags (_version, decl)
   = do  {       -- Populate the name cache with final versions of all
                 -- the names associated with the decl
-          main_name      <- lookupOrig mod (ifName decl)
+          main_name      <- lookupIfaceTop (ifName decl)
 
         -- Typecheck the thing, lazily
         -- NB. Firstly, the laziness is there in case we never need the
@@ -671,7 +669,7 @@ loadDecl ignore_prags mod (_version, decl)
                            Nothing    ->
                              pprPanic "loadDecl" (ppr main_name <+> ppr n $$ ppr (decl))
 
-        ; implicit_names <- mapM (lookupOrig mod) (ifaceDeclImplicitBndrs decl)
+        ; implicit_names <- mapM lookupIfaceTop (ifaceDeclImplicitBndrs decl)
 
 --         ; traceIf (text "Loading decl for " <> ppr main_name $$ ppr implicit_names)
         ; return $ (main_name, thing) :
diff --git a/compiler/iface/TcIface.hs b/compiler/iface/TcIface.hs
index 9480aec..a7c340f 100644
--- a/compiler/iface/TcIface.hs
+++ b/compiler/iface/TcIface.hs
@@ -736,7 +736,7 @@ tcIfaceVectInfo mod typeEnv (IfaceVectInfo
        }
   where
     vectVarMapping name
-      = do { vName <- lookupOrig mod (mkLocalisedOccName mod mkVectOcc name)
+      = do { vName <- lookupIfaceTop (mkLocalisedOccName mod mkVectOcc name)
            ; var   <- forkM (ptext (sLit "vect var")  <+> ppr name)  $
                         tcIfaceExtId name
            ; vVar  <- forkM (ptext (sLit "vect vVar [mod =") <+>
@@ -764,7 +764,7 @@ tcIfaceVectInfo mod typeEnv (IfaceVectInfo
           tcIfaceExtId name
 
     vectTyConVectMapping vars name
-      = do { vName  <- lookupOrig mod (mkLocalisedOccName mod mkVectTyConOcc name)
+      = do { vName  <- lookupIfaceTop (mkLocalisedOccName mod mkVectTyConOcc name)
            ; vectTyConMapping vars name vName
            }