)
import RnEnv
-import PrelNames ( mkUnboundName )
import DynFlags ( DynFlag(..) )
import Name
import NameEnv
rnTopBindsLHS fix_env binds =
(uncurry $ rnValBindsLHSFromDoc (topRecNameMaker fix_env)) (bindersAndDoc binds) binds
-rnTopBindsRHS :: [Name] -- the names bound by these binds
+rnTopBindsRHS :: NameSet -- Names bound by these binds
-> HsValBindsLR Name RdrName
-> RnM (HsValBinds Name, DefUses)
rnTopBindsRHS bound_names binds =
then rnTopBindsBoot binds
else rnValBindsRHSGen (\x -> x) -- don't trim free vars
bound_names binds }
-
--- wrapper if we don't need to do anything in between the left and right,
+-- Wrapper if we don't need to do anything in between the left and right,
-- or anything else in the scope of the left
--
--- never used when there are fixity declarations
+-- Never used when there are fixity declarations
rnTopBinds :: HsValBinds RdrName
-> RnM (HsValBinds Name, DefUses)
rnTopBinds b =
do nl <- rnTopBindsLHS emptyFsEnv b
let bound_names = map unLoc (collectHsValBinders nl)
- bindLocalNames bound_names $ rnTopBindsRHS bound_names nl
+ bindLocalNames bound_names $ rnTopBindsRHS (mkNameSet bound_names) nl
rnTopBindsBoot :: HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses)
rnValBindsRHSGen :: (FreeVars -> FreeVars) -- for trimming free var sets
-- The trimming function trims the free vars we attach to a
-- binding so that it stays reasonably small
- -> [Name] -- names bound by the LHSes
+ -> NameSet -- Names bound by the LHSes
-> HsValBindsLR Name RdrName
-> RnM (HsValBinds Name, DefUses)
rnValBindsRHSGen trim bound_names (ValBindsIn mbinds sigs) = do
-- rename the sigs
- env <- getGblEnv
- traceRn (ptext (sLit "Rename sigs") <+> ppr (tcg_rdr_env env))
- sigs' <- renameSigs (Just (mkNameSet bound_names)) okBindSig sigs
+ sigs' <- renameSigs (Just bound_names) okBindSig sigs
-- rename the RHSes
binds_w_dus <- mapBagM (rnBind (mkSigTvFn sigs') trim) mbinds
case depAnalBinds binds_w_dus of
-- it doesn't (and can't: we don't have the thing inside the binds) happen here
--
-- The client is also responsible for bringing the fixities into scope
-rnValBindsRHS :: [Name] -- names bound by the LHSes
+rnValBindsRHS :: NameSet -- names bound by the LHSes
-> HsValBindsLR Name RdrName
-> RnM (HsValBinds Name, DefUses)
rnValBindsRHS bound_names binds =
rnValBindsRHSGen (\ fvs -> -- only keep the names the names from this group
- intersectNameSet (mkNameSet bound_names) fvs) bound_names binds
+ intersectNameSet bound_names fvs) bound_names binds
-- for local binds
; bindLocalNamesFV_WithFixities bound_names new_fixities $ do
{ -- (C) Do the RHS and thing inside
- (binds', dus) <- rnValBindsRHS bound_names new_lhs
+ (binds', dus) <- rnValBindsRHS (mkNameSet bound_names) new_lhs
; (result, result_fvs) <- thing_inside binds'
-- Report unused bindings based on the (accurate)
; (grhss', fvs) <- rnGRHSs PatBindRhs grhss
-- No scoped type variables for pattern bindings
+ ; let fvs' = trim fvs
- ; return (L loc (PatBind { pat_lhs = pat,
+ ; fvs' `seq` -- See Note [Free-variable space leak]
+ return (L loc (PatBind { pat_lhs = pat,
pat_rhs = grhss',
pat_rhs_ty = placeHolderType,
- bind_fvs = trim fvs }),
+ bind_fvs = fvs' }),
bndrs, pat_fvs `plusFV` fvs) }
rnBind sig_fn
; (matches', fvs) <- bindSigTyVarsFV (sig_fn plain_name) $
-- bindSigTyVars tests for Opt_ScopedTyVars
rnMatchGroup (FunRhs plain_name inf) matches
+ ; let fvs' = trim fvs
; checkPrecMatch inf plain_name matches'
- ; return (L loc (FunBind { fun_id = name,
+ ; fvs' `seq` -- See Note [Free-variable space leak]
+ return (L loc (FunBind { fun_id = name,
fun_infix = inf,
fun_matches = matches',
- bind_fvs = trim fvs,
+ bind_fvs = fvs',
fun_co_fn = idHsWrapper,
fun_tick = Nothing }),
[plain_name], fvs)
}
rnBind _ _ b = pprPanic "rnBind" (ppr b)
-
+
+{-
+Note [Free-variable space leak]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+We have
+ fvs' = trim fvs
+and we seq fvs' before turning it as part of a record.
+
+The reason is that trim is sometimes something like
+ \xs -> intersectNameSet (mkNameSet bound_names) xs
+and we don't want to retain the list bound_names. This showed up in
+trac ticket #1136.
+-}
+
---------------------
depAnalBinds :: Bag (LHsBind Name, [Name], Uses)
-> ([(RecFlag, LHsBinds Name)], DefUses)
renameSig :: Maybe NameSet -> Sig RdrName -> RnM (Sig Name)
-- FixitySig is renamed elsewhere.
renameSig mb_names sig@(TypeSig v ty)
- = do { new_v <- lookupSigLocOccRn mb_names sig v
+ = do { new_v <- lookupSigOccRn mb_names sig v
; new_ty <- rnHsSigType (quotes (ppr v)) ty
; return (TypeSig new_v new_ty) }
; return (SpecInstSig new_ty) }
renameSig mb_names sig@(SpecSig v ty inl)
- = do { new_v <- lookupSigLocOccRn mb_names sig v
+ = do { new_v <- lookupSigOccRn mb_names sig v
; new_ty <- rnHsSigType (quotes (ppr v)) ty
; return (SpecSig new_v new_ty inl) }
renameSig mb_names sig@(InlineSig v s)
- = do { new_v <- lookupSigLocOccRn mb_names sig v
+ = do { new_v <- lookupSigOccRn mb_names sig v
; return (InlineSig new_v s) }
renameSig mb_names sig@(FixSig (FixitySig v f))
- = do { new_v <- lookupSigLocOccRn mb_names sig v
+ = do { new_v <- lookupSigOccRn mb_names sig v
; return (FixSig (FixitySig new_v f)) }
-
--- lookupSigOccRn is used for type signatures and pragmas
--- Is this valid?
--- module A
--- import M( f )
--- f :: Int -> Int
--- f x = x
--- It's clear that the 'f' in the signature must refer to A.f
--- The Haskell98 report does not stipulate this, but it will!
--- So we must treat the 'f' in the signature in the same way
--- as the binding occurrence of 'f', using lookupBndrRn
---
--- However, consider this case:
--- import M( f )
--- f :: Int -> Int
--- g x = x
--- We don't want to say 'f' is out of scope; instead, we want to
--- return the imported 'f', so that later on the reanamer will
--- correctly report "misplaced type sig".
-
-lookupSigLocOccRn :: Maybe NameSet -> Sig RdrName -> Located RdrName -> RnM (Located Name)
-lookupSigLocOccRn mb_names sig = wrapLocM (lookupSigOccRn mb_names sig)
-
-lookupSigOccRn :: Maybe NameSet -> Sig RdrName -> RdrName -> RnM Name
-lookupSigOccRn mb_names sig v
- = do { mb_n <- lookupBndrRn_maybe v
- ; case mb_n of {
- Just n -> case mb_names of {
- Nothing -> return n ;
- Just ns | n `elemNameSet` ns -> return n
- | otherwise -> bale_out_with local_msg } ;
-
- Nothing -> do
- { mb_n <- lookupGreRn_maybe v
- ; case mb_n of
- Just _ -> bale_out_with import_msg
- Nothing -> bale_out_with empty
- } }}
- where
- bale_out_with msg
- = do { addErr (sep [ ptext (sLit "The") <+> hsSigDoc sig
- <+> ptext (sLit "for") <+> quotes (ppr v)
- , nest 2 $ ptext (sLit "lacks an accompanying binding")]
- $$ nest 2 msg)
- ; return (mkUnboundName v) }
-
- local_msg = parens $ ptext (sLit "The") <+> hsSigDoc sig <+> ptext (sLit "must be given where")
- <+> quotes (ppr v) <+> ptext (sLit "is declared")
-
- import_msg = parens $ ptext (sLit "You cannot give a") <+> hsSigDoc sig
- <+> ptext (sLit "an imported value")
\end{code}
projects / ghc-hetmet.git / blobdiff