%
-% (c) The GRASP/AQUA Project, Glasgow University, 1993-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
%
\section[CoreLint]{A ``lint'' pass to check for Core correctness}
\begin{code}
module CoreLint (
lintCoreBindings,
- lintUnfolding
+ lintUnfolding,
+ beginPass, endPass
) where
#include "HsVersions.h"
import CmdLineOpts ( opt_D_show_passes, opt_DoCoreLinting )
import CoreSyn
+import CoreUtils ( idFreeVars )
import Bag
-import Kind ( hasMoreBoxityInfo, Kind{-instance-} )
-import Literal ( literalType, Literal{-instance-} )
-import Id ( idType, isBottomingId, dataConRepType, isDataCon, isNewCon, isAlgCon,
- dataConArgTys, GenId{-instances-},
- emptyIdSet, mkIdSet,
- unionIdSets, elementOfIdSet, IdSet,
- Id
- )
-import Maybes ( catMaybes )
-import Name ( isLocallyDefined, getSrcLoc, Name{-instance NamedThing-},
- NamedThing(..) )
+import Const ( Con(..), DataCon, conType, conOkForApp, conOkForAlt )
+import Id ( isConstantId, idMustBeINLINEd )
+import Var ( IdOrTyVar, Id, TyVar, idType, tyVarKind, isTyVar, isId )
+import VarSet
+import VarEnv ( mkVarEnv )
+import Name ( isLocallyDefined, getSrcLoc )
import PprCore
-import ErrUtils ( doIfSet, ghcExit )
-import PprType ( GenType, GenTyVar, TyCon )
-import PrimOp ( primOpType )
+import ErrUtils ( doIfSet, dumpIfSet, ghcExit, Message,
+ ErrMsg, addErrLocHdrLine, pprBagOfErrors )
import PrimRep ( PrimRep(..) )
-import SrcLoc ( SrcLoc )
-import Type ( mkFunTy, splitFunTy_maybe, mkForAllTy,
- splitForAllTy_maybe,
- isUnpointedType, typeKind, instantiateTy,
- splitAlgTyConApp_maybe, Type
+import SrcLoc ( SrcLoc, noSrcLoc, isNoSrcLoc )
+import Type ( Type, Kind, tyVarsOfType,
+ splitFunTy_maybe, mkPiType, mkTyVarTy,
+ splitForAllTy_maybe, splitTyConApp_maybe,
+ isUnLiftedType, typeKind, substTy,
+ splitAlgTyConApp_maybe,
+ isUnboxedTupleType,
+ hasMoreBoxityInfo
)
-import TyCon ( isPrimTyCon, isDataTyCon )
-import TyVar ( TyVar, tyVarKind, mkTyVarEnv )
-import ErrUtils ( ErrMsg )
-import Unique ( Unique )
-import Util ( zipEqual )
+import TyCon ( TyCon, isPrimTyCon, tyConDataCons )
import Outputable
-infixr 9 `thenL`, `seqL`, `thenMaybeL`
+infixr 9 `thenL`, `seqL`
\end{code}
%************************************************************************
%* *
+\subsection{Start and end pass}
+%* *
+%************************************************************************
+
+@beginPass@ and @endPass@ don't really belong here, but it makes a convenient
+place for them. They print out stuff before and after core passes,
+and do Core Lint when necessary.
+
+\begin{code}
+beginPass :: String -> IO ()
+beginPass pass_name
+ | opt_D_show_passes
+ = hPutStr stderr ("*** " ++ pass_name ++ "\n")
+ | otherwise
+ = return ()
+
+
+endPass :: String -> Bool -> [CoreBind] -> IO [CoreBind]
+endPass pass_name dump_flag binds
+ = do
+ -- Report verbosely, if required
+ dumpIfSet dump_flag pass_name
+ (pprCoreBindings binds)
+
+ -- Type check
+ lintCoreBindings pass_name binds
+
+ return binds
+\end{code}
+
+
+%************************************************************************
+%* *
\subsection[lintCoreBindings]{@lintCoreBindings@: Top-level interface}
%* *
%************************************************************************
--
-- * Oversaturated type app after specialisation (eta reduction
-- may well be happening...);
- --
- -- Note: checkTyApp is usually followed by a call to checkSpecTyApp.
- --
\begin{code}
-lintCoreBindings :: String -> Bool -> [CoreBinding] -> IO ()
+lintCoreBindings :: String -> [CoreBind] -> IO ()
-lintCoreBindings whoDunnit spec_done binds
+lintCoreBindings whoDunnit binds
| not opt_DoCoreLinting
= return ()
-lintCoreBindings whoDunnit spec_done binds
- = case (initL (lint_binds binds) spec_done) of
+lintCoreBindings whoDunnit binds
+ = case (initL (lint_binds binds)) of
Nothing -> doIfSet opt_D_show_passes
(hPutStr stderr ("*** Core Linted result of " ++ whoDunnit ++ "\n"))
(it is very painful to catch errors otherwise):
\begin{code}
-lintUnfolding :: SrcLoc -> CoreExpr -> Maybe CoreExpr
+lintUnfolding :: SrcLoc
+ -> [IdOrTyVar] -- Treat these as in scope
+ -> CoreExpr
+ -> Maybe CoreExpr
-lintUnfolding locn expr
+lintUnfolding locn vars expr
+ | not opt_DoCoreLinting
+ = Just expr
+
+ | otherwise
= case
- (initL (addLoc (ImportedUnfolding locn) (lintCoreExpr expr))
- True{-pretend spec done-})
+ initL (addLoc (ImportedUnfolding locn) $
+ addInScopeVars vars $
+ lintCoreExpr expr)
of
Nothing -> Just expr
Just msg ->
Check a core binding, returning the list of variables bound.
\begin{code}
-lintCoreBinding :: CoreBinding -> LintM [Id]
+lintCoreBinding :: CoreBind -> LintM [Id]
lintCoreBinding (NonRec binder rhs)
= lintSingleBinding (binder,rhs) `seqL` returnL [binder]
mapL lintSingleBinding pairs `seqL` returnL binders
)
where
- binders = [b | (b,_) <- pairs]
+ binders = map fst pairs
lintSingleBinding (binder,rhs)
- = addLoc (RhsOf binder) (
+ = addLoc (RhsOf binder) $
+
-- Check the rhs
- lintCoreExpr rhs
+ lintCoreExpr rhs `thenL` \ ty ->
- `thenL` \maybe_ty ->
-- Check match to RHS type
- (case maybe_ty of
- Nothing -> returnL ()
- Just ty -> checkTys (idType binder) ty (mkRhsMsg binder ty))
+ lintBinder binder `seqL`
+ checkTys binder_ty ty (mkRhsMsg binder ty) `seqL`
- `seqL`
- -- Check (not isUnpointedType)
- checkIfSpecDoneL (not (isUnpointedType (idType binder)))
- (mkRhsPrimMsg binder rhs)
+ -- Check (not isUnLiftedType) (also checks for bogus unboxed tuples)
+ checkL (not (isUnLiftedType binder_ty))
+ (mkRhsPrimMsg binder rhs) `seqL`
+ -- Check whether binder's specialisations contain any out-of-scope variables
+ mapL (checkBndrIdInScope binder) bndr_vars `seqL`
+ returnL ()
+
-- We should check the unfolding, if any, but this is tricky because
-- the unfolding is a SimplifiableCoreExpr. Give up for now.
- )
+ where
+ binder_ty = idType binder
+ bndr_vars = varSetElems (idFreeVars binder)
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-lintCoreExpr :: CoreExpr -> LintM (Maybe Type) -- Nothing if error found
+lintCoreExpr :: CoreExpr -> LintM Type
lintCoreExpr (Var var)
- | isAlgCon var = returnL (Just (idType var))
+ | isConstantId var = returnL (idType var)
-- Micro-hack here... Class decls generate applications of their
-- dictionary constructor, but don't generate a binding for the
-- constructor (since it would never be used). After a single round
-- variables as the function in an application.
-- The hack here simply doesn't check for out-of-scope-ness for
-- data constructors (at least, in a function position).
+ -- Ditto primitive Ids
+
+ | otherwise = checkIdInScope var `seqL` returnL (idType var)
- | otherwise = checkInScope var `seqL` returnL (Just (idType var))
+lintCoreExpr (Note (Coerce to_ty from_ty) expr)
+ = lintCoreExpr expr `thenL` \ expr_ty ->
+ lintTy to_ty `seqL`
+ lintTy from_ty `seqL`
+ checkTys from_ty expr_ty (mkCoerceErr from_ty expr_ty) `seqL`
+ returnL to_ty
-lintCoreExpr (Lit lit) = returnL (Just (literalType lit))
-lintCoreExpr (SCC _ expr) = lintCoreExpr expr
-lintCoreExpr e@(Coerce coercion ty expr)
- = lintCoercion e coercion `seqL`
- lintCoreExpr expr `seqL` returnL (Just ty)
+lintCoreExpr (Note other_note expr)
+ = lintCoreExpr expr
lintCoreExpr (Let binds body)
= lintCoreBinding binds `thenL` \binders ->
(addInScopeVars binders (lintCoreExpr body))
lintCoreExpr e@(Con con args)
- = checkL (isDataCon con) (mkConErrMsg e) `seqL`
- lintCoreArgs {-False-} e (dataConRepType con) args
- -- Note: we don't check for primitive types in these arguments
-
-lintCoreExpr e@(Prim op args)
- = lintCoreArgs {-True-} e (primOpType op) args
- -- Note: we do check for primitive types in these arguments
-
-lintCoreExpr e@(App fun@(Var v) arg) | isBottomingId v
- = lintCoreExpr fun `thenMaybeL` \ ty -> lintCoreArg {-False-} e ty arg
- -- Note: we don't check for primitive types in argument to 'error'
+ = addLoc (AnExpr e) $
+ checkL (conOkForApp con) (mkConAppMsg e) `seqL`
+ lintCoreArgs (conType con) args
lintCoreExpr e@(App fun arg)
- = lintCoreExpr fun `thenMaybeL` \ty -> lintCoreArg {-True-} e ty arg
- -- Note: we do check for primitive types in this argument
-
-lintCoreExpr (Lam (ValBinder var) expr)
- = addLoc (LambdaBodyOf var)
- (addInScopeVars [var]
- (lintCoreExpr expr `thenMaybeL` \ty ->
- returnL (Just (mkFunTy (idType var) ty))))
-
-lintCoreExpr (Lam (TyBinder tyvar) expr)
- = lintCoreExpr expr `thenMaybeL` \ty ->
- returnL (Just(mkForAllTy tyvar ty))
- -- ToDo: Should add in-scope type variable at this point
-
-lintCoreExpr e@(Case scrut alts)
- = lintCoreExpr scrut `thenMaybeL` \ty ->
- lintCoreAlts alts ty
+ = lintCoreExpr fun `thenL` \ ty ->
+ addLoc (AnExpr e) $
+ lintCoreArg ty arg
+
+lintCoreExpr (Lam var expr)
+ = addLoc (LambdaBodyOf var) $
+ checkL (not (isUnboxedTupleType (idType var))) (mkUnboxedTupleMsg var)
+ `seqL`
+ (addInScopeVars [var] $
+ lintCoreExpr expr `thenL` \ ty ->
+ returnL (mkPiType var ty))
+
+lintCoreExpr e@(Case scrut var alts)
+ = -- Check the scrutinee
+ lintCoreExpr scrut `thenL` \ scrut_ty ->
+
+ -- Check the binder
+ lintBinder var `seqL`
+
+ -- If this is an unboxed tuple case, then the binder must be dead
+ {-
+ checkL (if isUnboxedTupleType (idType var)
+ then isDeadBinder var
+ else True) (mkUnboxedTupleMsg var) `seqL`
+ -}
+
+ checkTys (idType var) scrut_ty (mkScrutMsg var scrut_ty) `seqL`
+
+ addInScopeVars [var] (
+
+ -- Check the alternatives
+ checkAllCasesCovered e scrut_ty alts `seqL`
+ mapL (lintCoreAlt scrut_ty) alts `thenL` \ (alt_ty : alt_tys) ->
+ mapL (check alt_ty) alt_tys `seqL`
+ returnL alt_ty)
+ where
+ check alt_ty1 alt_ty2 = checkTys alt_ty1 alt_ty2 (mkCaseAltMsg e)
+
+lintCoreExpr e@(Type ty)
+ = addErrL (mkStrangeTyMsg e)
\end{code}
%************************************************************************
applications to primitive types as being errors.
\begin{code}
-lintCoreArgs :: {-Bool ->-} CoreExpr -> Type -> [CoreArg] -> LintM (Maybe Type)
+lintCoreArgs :: Type -> [CoreArg] -> LintM Type
-lintCoreArgs _ ty [] = returnL (Just ty)
-lintCoreArgs e ty (a : args)
- = lintCoreArg e ty a `thenMaybeL` \ res ->
- lintCoreArgs e res args
+lintCoreArgs ty [] = returnL ty
+lintCoreArgs ty (a : args)
+ = lintCoreArg ty a `thenL` \ res ->
+ lintCoreArgs res args
\end{code}
-%************************************************************************
-%* *
-\subsection[lintCoreArg]{lintCoreArg}
-%* *
-%************************************************************************
-
\begin{code}
-lintCoreArg :: {-Bool ->-} CoreExpr -> Type -> CoreArg -> LintM (Maybe Type)
+lintCoreArg :: Type -> CoreArg -> LintM Type
-lintCoreArg e ty (LitArg lit)
+lintCoreArg ty a@(Type arg_ty)
+ = lintTy arg_ty `seqL`
+ lintTyApp ty arg_ty
+
+lintCoreArg fun_ty arg
= -- Make sure function type matches argument
- case (splitFunTy_maybe ty) of
- Just (arg,res) | (lit_ty == arg) -> returnL(Just res)
- _ -> addErrL (mkAppMsg ty lit_ty e) `seqL` returnL Nothing
- where
- lit_ty = literalType lit
-
-lintCoreArg e ty (VarArg v)
- = -- Make sure variable is bound
- checkInScope v `seqL`
- -- Make sure function type matches argument
- case (splitFunTy_maybe ty) of
- Just (arg,res) | (var_ty == arg) -> returnL(Just res)
- _ -> addErrL (mkAppMsg ty var_ty e) `seqL` returnL Nothing
- where
- var_ty = idType v
+ lintCoreExpr arg `thenL` \ arg_ty ->
+ case (splitFunTy_maybe fun_ty) of
+ Just (arg,res) | (arg_ty == arg) -> returnL res
+ _ -> addErrL (mkAppMsg fun_ty arg_ty)
+\end{code}
-lintCoreArg e ty a@(TyArg arg_ty)
- = -- ToDo: Check that ty is well-kinded and has no unbound tyvars
- case (splitForAllTy_maybe ty) of
- Nothing -> addErrL (mkTyAppMsg SLIT("Illegal") ty arg_ty e) `seqL` returnL Nothing
+\begin{code}
+lintTyApp ty arg_ty
+ = case splitForAllTy_maybe ty of
+ Nothing -> addErrL (mkTyAppMsg ty arg_ty)
Just (tyvar,body) ->
let
-- error :: forall a:*. String -> a
-- and then apply it to both boxed and unboxed types.
then
- returnL(Just(instantiateTy (mkTyVarEnv [(tyvar,arg_ty)]) body))
+ returnL (substTy (mkVarEnv [(tyvar,arg_ty)]) body)
else
- pprTrace "lintCoreArg:kinds:" (hsep [ppr tyvar_kind, ppr argty_kind]) $
- addErrL (mkKindErrMsg tyvar arg_ty e) `seqL` returnL Nothing
+ addErrL (mkKindErrMsg tyvar arg_ty)
+
+lintTyApps fun_ty []
+ = returnL fun_ty
+
+lintTyApps fun_ty (arg_ty : arg_tys)
+ = lintTyApp fun_ty arg_ty `thenL` \ fun_ty' ->
+ lintTyApps fun_ty' arg_tys
\end{code}
+
+
%************************************************************************
%* *
\subsection[lintCoreAlts]{lintCoreAlts}
%************************************************************************
\begin{code}
-lintCoreAlts :: CoreCaseAlts
- -> Type -- Type of scrutinee
--- -> TyCon -- TyCon pinned on the case
- -> LintM (Maybe Type) -- Type of alternatives
-
-lintCoreAlts whole_alts@(AlgAlts alts deflt) ty --tycon
- = -- Check tycon is not a primitive tycon
--- addErrIfL (isPrimTyCon tycon) (mkCasePrimMsg tycon)
--- `seqL`
- -- Check we are scrutinising a proper datatype
- -- (ToDo: robustify)
--- addErrIfL (not (tyConFamilySize tycon >= 1)) (mkCaseAbstractMsg tycon)
--- `seqL`
- lintDeflt deflt ty
- `thenL` \maybe_deflt_ty ->
- mapL (lintAlgAlt ty {-tycon-}) alts
- `thenL` \maybe_alt_tys ->
- -- Check the result types
- case catMaybes (maybe_deflt_ty : maybe_alt_tys) of
- [] -> returnL Nothing
-
- (first_ty:tys) -> mapL check tys `seqL`
- returnL (Just first_ty)
- where
- check ty = checkTys first_ty ty (mkCaseAltMsg whole_alts)
-
-lintCoreAlts whole_alts@(PrimAlts alts deflt) ty --tycon
- = -- Check tycon is a primitive tycon
--- addErrIfL (not (isPrimTyCon tycon)) (mkCaseNotPrimMsg tycon)
--- `seqL`
- mapL (lintPrimAlt ty) alts
- `thenL` \maybe_alt_tys ->
- lintDeflt deflt ty
- `thenL` \maybe_deflt_ty ->
- -- Check the result types
- case catMaybes (maybe_deflt_ty : maybe_alt_tys) of
- [] -> returnL Nothing
-
- (first_ty:tys) -> mapL check tys `seqL`
- returnL (Just first_ty)
- where
- check ty = checkTys first_ty ty (mkCaseAltMsg whole_alts)
-
-lintAlgAlt scrut_ty (con,args,rhs)
- = (case splitAlgTyConApp_maybe scrut_ty of
- Just (tycon, tys_applied, cons) | isDataTyCon tycon ->
- let
- arg_tys = dataConArgTys con tys_applied
- in
- checkL (con `elem` cons) (mkAlgAltMsg2 scrut_ty con) `seqL`
- checkL (length arg_tys == length args) (mkAlgAltMsg3 con args)
- `seqL`
- mapL check (zipEqual "lintAlgAlt" arg_tys args) `seqL`
- returnL ()
-
- other -> addErrL (mkAlgAltMsg1 scrut_ty)
- ) `seqL`
- addInScopeVars args (
- lintCoreExpr rhs
- )
+checkAllCasesCovered e ty [] = addErrL (mkNullAltsMsg e)
+
+checkAllCasesCovered e ty [(DEFAULT,_,_)] = nopL
+
+checkAllCasesCovered e scrut_ty alts
+ = case splitTyConApp_maybe scrut_ty of {
+ Nothing -> addErrL (badAltsMsg e);
+ Just (tycon, tycon_arg_tys) ->
+
+ if isPrimTyCon tycon then
+ checkL (hasDefault alts) (nonExhaustiveAltsMsg e)
+ else
+#ifdef DEBUG
+ -- Algebraic cases are not necessarily exhaustive, because
+ -- the simplifer correctly eliminates case that can't
+ -- possibly match.
+ -- This code just emits a message to say so
+ let
+ missing_cons = filter not_in_alts (tyConDataCons tycon)
+ not_in_alts con = all (not_in_alt con) alts
+ not_in_alt con (DataCon con', _, _) = con /= con'
+ not_in_alt con other = True
+
+ case_bndr = case e of { Case _ bndr alts -> bndr }
+ in
+ if not (hasDefault alts || null missing_cons) then
+ pprTrace "Exciting (but not a problem)! Non-exhaustive case:"
+ (ppr case_bndr <+> ppr missing_cons)
+ nopL
+ else
+#endif
+ nopL }
+
+hasDefault [] = False
+hasDefault ((DEFAULT,_,_) : alts) = True
+hasDefault (alt : alts) = hasDefault alts
+\end{code}
+
+\begin{code}
+lintCoreAlt :: Type -- Type of scrutinee
+ -> CoreAlt
+ -> LintM Type -- Type of alternatives
+
+lintCoreAlt scrut_ty alt@(DEFAULT, args, rhs)
+ = checkL (null args) (mkDefaultArgsMsg args) `seqL`
+ lintCoreExpr rhs
+
+lintCoreAlt scrut_ty alt@(con, args, rhs)
+ = addLoc (CaseAlt alt) (
+
+ checkL (conOkForAlt con) (mkConAltMsg con) `seqL`
+
+ mapL (\arg -> checkL (not (isUnboxedTupleType (idType arg)))
+ (mkUnboxedTupleMsg arg)) args `seqL`
+
+ addInScopeVars args (
+
+ -- Check the pattern
+ -- Scrutinee type must be a tycon applicn; checked by caller
+ -- This code is remarkably compact considering what it does!
+ -- NB: args must be in scope here so that the lintCoreArgs line works.
+ case splitTyConApp_maybe scrut_ty of { Just (tycon, tycon_arg_tys) ->
+ lintTyApps (conType con) tycon_arg_tys `thenL` \ con_type ->
+ lintCoreArgs con_type (map mk_arg args) `thenL` \ con_result_ty ->
+ checkTys con_result_ty scrut_ty (mkBadPatMsg con_result_ty scrut_ty)
+ } `seqL`
+
+ -- Check the RHS
+ lintCoreExpr rhs
+ ))
where
- check (ty, arg) = checkTys ty (idType arg) (mkAlgAltMsg4 ty arg)
-
- -- elem: yes, the elem-list here can sometimes be long-ish,
- -- but as it's use-once, probably not worth doing anything different
- -- We give it its own copy, so it isn't overloaded.
- elem _ [] = False
- elem x (y:ys) = x==y || elem x ys
-
-lintPrimAlt ty alt@(lit,rhs)
- = checkTys (literalType lit) ty (mkPrimAltMsg alt) `seqL`
- lintCoreExpr rhs
-
-lintDeflt NoDefault _ = returnL Nothing
-lintDeflt deflt@(BindDefault binder rhs) ty
- = checkTys (idType binder) ty (mkDefltMsg deflt) `seqL`
- addInScopeVars [binder] (lintCoreExpr rhs)
+ mk_arg b | isTyVar b = Type (mkTyVarTy b)
+ | otherwise = Var b
\end{code}
%************************************************************************
%* *
-\subsection[lint-coercion]{Coercion}
+\subsection[lint-types]{Types}
%* *
%************************************************************************
\begin{code}
-lintCoercion e (CoerceIn con) = check_con e con
-lintCoercion e (CoerceOut con) = check_con e con
-
-check_con e con = checkL (isNewCon con)
- (mkCoerceErrMsg e)
+lintBinder :: IdOrTyVar -> LintM ()
+lintBinder v = nopL
+-- ToDo: lint its type
+
+lintTy :: Type -> LintM ()
+lintTy ty = mapL checkIdInScope (varSetElems (tyVarsOfType ty)) `seqL`
+ returnL ()
+ -- ToDo: check the kind structure of the type
\end{code}
-
+
%************************************************************************
%* *
\subsection[lint-monad]{The Lint monad}
%************************************************************************
\begin{code}
-type LintM a = Bool -- True <=> specialisation has been done
- -> [LintLocInfo] -- Locations
+type LintM a = [LintLocInfo] -- Locations
-> IdSet -- Local vars in scope
-> Bag ErrMsg -- Error messages so far
- -> (a, Bag ErrMsg) -- Result and error messages (if any)
+ -> (Maybe a, Bag ErrMsg) -- Result and error messages (if any)
data LintLocInfo
= RhsOf Id -- The variable bound
| LambdaBodyOf Id -- The lambda-binder
| BodyOfLetRec [Id] -- One of the binders
+ | CaseAlt CoreAlt -- Pattern of a case alternative
+ | AnExpr CoreExpr -- Some expression
| ImportedUnfolding SrcLoc -- Some imported unfolding (ToDo: say which)
-
-instance Outputable LintLocInfo where
- ppr (RhsOf v)
- = ppr (getSrcLoc v) <> colon <+>
- brackets (ptext SLIT("RHS of") <+> pp_binders [v])
-
- ppr (LambdaBodyOf b)
- = ppr (getSrcLoc b) <> colon <+>
- brackets (ptext SLIT("in body of lambda with binder") <+> pp_binder b)
-
- ppr (BodyOfLetRec bs)
- = ppr (getSrcLoc (head bs)) <> colon <+>
- brackets (ptext SLIT("in body of letrec with binders") <+> pp_binders bs)
-
- ppr (ImportedUnfolding locn)
- = ppr locn <> colon <+>
- brackets (ptext SLIT("in an imported unfolding"))
-
-pp_binders :: [Id] -> SDoc
-pp_binders bs = sep (punctuate comma (map pp_binder bs))
-
-pp_binder :: Id -> SDoc
-pp_binder b = hsep [ppr b, text "::", ppr (idType b)]
\end{code}
\begin{code}
-initL :: LintM a -> Bool -> Maybe ErrMsg
-initL m spec_done
- = case (m spec_done [] emptyIdSet emptyBag) of { (_, errs) ->
+initL :: LintM a -> Maybe Message
+initL m
+ = case (m [] emptyVarSet emptyBag) of { (_, errs) ->
if isEmptyBag errs then
Nothing
else
- Just (vcat (bagToList errs))
+ Just (pprBagOfErrors errs)
}
returnL :: a -> LintM a
-returnL r spec loc scope errs = (r, errs)
+returnL r loc scope errs = (Just r, errs)
+
+nopL :: LintM a
+nopL loc scope errs = (Nothing, errs)
thenL :: LintM a -> (a -> LintM b) -> LintM b
-thenL m k spec loc scope errs
- = case m spec loc scope errs of
- (r, errs') -> k r spec loc scope errs'
+thenL m k loc scope errs
+ = case m loc scope errs of
+ (Just r, errs') -> k r loc scope errs'
+ (Nothing, errs') -> (Nothing, errs')
seqL :: LintM a -> LintM b -> LintM b
-seqL m k spec loc scope errs
- = case m spec loc scope errs of
- (_, errs') -> k spec loc scope errs'
-
-thenMaybeL :: LintM (Maybe a) -> (a -> LintM (Maybe b)) -> LintM (Maybe b)
-thenMaybeL m k spec loc scope errs
- = case m spec loc scope errs of
- (Nothing, errs2) -> (Nothing, errs2)
- (Just r, errs2) -> k r spec loc scope errs2
+seqL m k loc scope errs
+ = case m loc scope errs of
+ (_, errs') -> k loc scope errs'
mapL :: (a -> LintM b) -> [a] -> LintM [b]
mapL f [] = returnL []
= f x `thenL` \ r ->
mapL f xs `thenL` \ rs ->
returnL (r:rs)
-
-mapMaybeL :: (a -> LintM (Maybe b)) -> [a] -> LintM (Maybe [b])
- -- Returns Nothing if anything fails
-mapMaybeL f [] = returnL (Just [])
-mapMaybeL f (x:xs)
- = f x `thenMaybeL` \ r ->
- mapMaybeL f xs `thenMaybeL` \ rs ->
- returnL (Just (r:rs))
\end{code}
\begin{code}
-checkL :: Bool -> ErrMsg -> LintM ()
-checkL True msg spec loc scope errs = ((), errs)
-checkL False msg spec loc scope errs = ((), addErr errs msg loc)
+checkL :: Bool -> Message -> LintM ()
+checkL True msg loc scope errs = (Nothing, errs)
+checkL False msg loc scope errs = (Nothing, addErr errs msg loc)
-checkIfSpecDoneL :: Bool -> ErrMsg -> LintM ()
-checkIfSpecDoneL True msg spec loc scope errs = ((), errs)
-checkIfSpecDoneL False msg True loc scope errs = ((), addErr errs msg loc)
-checkIfSpecDoneL False msg False loc scope errs = ((), errs)
+addErrL :: Message -> LintM a
+addErrL msg loc scope errs = (Nothing, addErr errs msg loc)
-addErrL :: ErrMsg -> LintM ()
-addErrL msg spec loc scope errs = ((), addErr errs msg loc)
-
-addErr :: Bag ErrMsg -> ErrMsg -> [LintLocInfo] -> Bag ErrMsg
+addErr :: Bag ErrMsg -> Message -> [LintLocInfo] -> Bag ErrMsg
addErr errs_so_far msg locs
= ASSERT (not (null locs))
- errs_so_far `snocBag` (hang (ppr (head locs)) 4 msg)
+ errs_so_far `snocBag` mk_msg msg
+ where
+ (loc, pref) = dumpLoc (head locs)
+
+ mk_msg msg
+ | isNoSrcLoc loc = (loc, hang pref 4 msg)
+ | otherwise = addErrLocHdrLine loc pref msg
addLoc :: LintLocInfo -> LintM a -> LintM a
-addLoc extra_loc m spec loc scope errs
- = m spec (extra_loc:loc) scope errs
-
-addInScopeVars :: [Id] -> LintM a -> LintM a
-addInScopeVars ids m spec loc scope errs
- = -- We check if these "new" ids are already
- -- in scope, i.e., we have *shadowing* going on.
- -- For now, it's just a "trace"; we may make
- -- a real error out of it...
- let
- new_set = mkIdSet ids
+addLoc extra_loc m loc scope errs
+ = m (extra_loc:loc) scope errs
--- shadowed = scope `intersectIdSets` new_set
- in
--- After adding -fliberate-case, Simon decided he likes shadowed
--- names after all. WDP 94/07
--- (if isEmptyUniqSet shadowed
--- then id
--- else pprTrace "Shadowed vars:" (ppr (uniqSetToList shadowed))) (
- m spec loc (scope `unionIdSets` new_set) errs
--- )
+addInScopeVars :: [IdOrTyVar] -> LintM a -> LintM a
+addInScopeVars ids m loc scope errs
+ = m loc (scope `unionVarSet` mkVarSet ids) errs
\end{code}
\begin{code}
-checkInScope :: Id -> LintM ()
-checkInScope id spec loc scope errs
- = let
- id_name = getName id
- in
- if isLocallyDefined id_name && not (id `elementOfIdSet` scope) then
- ((), addErr errs (hsep [ppr id, ptext SLIT("is out of scope")]) loc)
- else
- ((),errs)
-
-checkTys :: Type -> Type -> ErrMsg -> LintM ()
-checkTys ty1 ty2 msg spec loc scope errs
- = if ty1 == ty2 then ((), errs) else ((), addErr errs msg loc)
+checkIdInScope :: IdOrTyVar -> LintM ()
+checkIdInScope id
+ = checkInScope (ptext SLIT("is out of scope")) id
+
+checkBndrIdInScope :: IdOrTyVar -> IdOrTyVar -> LintM ()
+checkBndrIdInScope binder id
+ = checkInScope msg id
+ where
+ msg = ptext SLIT("is out of scope inside info for") <+>
+ ppr binder
+
+checkInScope :: SDoc -> IdOrTyVar -> LintM ()
+checkInScope loc_msg var loc scope errs
+ | isLocallyDefined var
+ && not (var `elemVarSet` scope)
+ && not (isId var && idMustBeINLINEd var) -- Constructors and dict selectors
+ -- don't have bindings,
+ -- just MustInline prags
+ = (Nothing, addErr errs (hsep [ppr var, loc_msg]) loc)
+ | otherwise
+ = (Nothing,errs)
+
+checkTys :: Type -> Type -> Message -> LintM ()
+checkTys ty1 ty2 msg loc scope errs
+ | ty1 == ty2 = (Nothing, errs)
+ | otherwise = (Nothing, addErr errs msg loc)
\end{code}
+
+%************************************************************************
+%* *
+\subsection{Error messages}
+%* *
+%************************************************************************
+
\begin{code}
-mkConErrMsg e
- = ($$) (ptext SLIT("Application of newtype constructor:"))
- (ppr e)
+dumpLoc (RhsOf v)
+ = (getSrcLoc v, brackets (ptext SLIT("RHS of") <+> pp_binders [v]))
+
+dumpLoc (LambdaBodyOf b)
+ = (getSrcLoc b, brackets (ptext SLIT("in body of lambda with binder") <+> pp_binder b))
+
+dumpLoc (BodyOfLetRec bs)
+ = ( getSrcLoc (head bs), brackets (ptext SLIT("in body of letrec with binders") <+> pp_binders bs))
-mkCoerceErrMsg e
- = ($$) (ptext SLIT("Coercion using a datatype constructor:"))
- (ppr e)
+dumpLoc (AnExpr e)
+ = (noSrcLoc, text "In the expression:" <+> ppr e)
+dumpLoc (CaseAlt (con, args, rhs))
+ = (noSrcLoc, text "In a case pattern:" <+> parens (ppr con <+> ppr args))
+
+dumpLoc (ImportedUnfolding locn)
+ = (locn, brackets (ptext SLIT("in an imported unfolding")))
+
+pp_binders :: [Id] -> SDoc
+pp_binders bs = sep (punctuate comma (map pp_binder bs))
-mkCaseAltMsg :: CoreCaseAlts -> ErrMsg
-mkCaseAltMsg alts
- = ($$) (ptext SLIT("Type of case alternatives not the same:"))
- (ppr alts)
+pp_binder :: Id -> SDoc
+pp_binder b = hsep [ppr b, dcolon, ppr (idType b)]
+\end{code}
-mkCaseAbstractMsg :: TyCon -> ErrMsg
-mkCaseAbstractMsg tycon
- = ($$) (ptext SLIT("An algebraic case on some weird type:"))
- (ppr tycon)
+\begin{code}
+------------------------------------------------------
+-- Messages for case expressions
+
+mkConAppMsg :: CoreExpr -> Message
+mkConAppMsg e
+ = hang (text "Application of newtype constructor:")
+ 4 (ppr e)
+
+mkConAltMsg :: Con -> Message
+mkConAltMsg con
+ = text "PrimOp in case pattern:" <+> ppr con
+
+mkNullAltsMsg :: CoreExpr -> Message
+mkNullAltsMsg e
+ = hang (text "Case expression with no alternatives:")
+ 4 (ppr e)
+
+mkDefaultArgsMsg :: [IdOrTyVar] -> Message
+mkDefaultArgsMsg args
+ = hang (text "DEFAULT case with binders")
+ 4 (ppr args)
+
+mkCaseAltMsg :: CoreExpr -> Message
+mkCaseAltMsg e
+ = hang (text "Type of case alternatives not the same:")
+ 4 (ppr e)
+
+mkScrutMsg :: Id -> Type -> Message
+mkScrutMsg var scrut_ty
+ = vcat [text "Result binder in case doesn't match scrutinee:" <+> ppr var,
+ text "Result binder type:" <+> ppr (idType var),
+ text "Scrutinee type:" <+> ppr scrut_ty]
+
+badAltsMsg :: CoreExpr -> Message
+badAltsMsg e
+ = hang (text "Case statement scrutinee is not a data type:")
+ 4 (ppr e)
+
+nonExhaustiveAltsMsg :: CoreExpr -> Message
+nonExhaustiveAltsMsg e
+ = hang (text "Case expression with non-exhaustive alternatives")
+ 4 (ppr e)
+
+mkBadPatMsg :: Type -> Type -> Message
+mkBadPatMsg con_result_ty scrut_ty
+ = vcat [
+ text "In a case alternative, pattern result type doesn't match scrutinee type:",
+ text "Pattern result type:" <+> ppr con_result_ty,
+ text "Scrutinee type:" <+> ppr scrut_ty
+ ]
-mkDefltMsg :: CoreCaseDefault -> ErrMsg
-mkDefltMsg deflt
- = ($$) (ptext SLIT("Binder in case default doesn't match type of scrutinee:"))
- (ppr deflt)
+------------------------------------------------------
+-- Other error messages
-mkAppMsg :: Type -> Type -> CoreExpr -> ErrMsg
-mkAppMsg fun arg expr
+mkAppMsg :: Type -> Type -> Message
+mkAppMsg fun arg
= vcat [ptext SLIT("Argument value doesn't match argument type:"),
hang (ptext SLIT("Fun type:")) 4 (ppr fun),
- hang (ptext SLIT("Arg type:")) 4 (ppr arg),
- hang (ptext SLIT("Expression:")) 4 (pprCoreExpr expr)]
+ hang (ptext SLIT("Arg type:")) 4 (ppr arg)]
-mkKindErrMsg :: TyVar -> Type -> CoreExpr -> ErrMsg
-mkKindErrMsg tyvar arg_ty expr
+mkKindErrMsg :: TyVar -> Type -> Message
+mkKindErrMsg tyvar arg_ty
= vcat [ptext SLIT("Kinds don't match in type application:"),
hang (ptext SLIT("Type variable:"))
- 4 (ppr tyvar <+> ptext SLIT("::") <+> ppr (tyVarKind tyvar)),
+ 4 (ppr tyvar <+> dcolon <+> ppr (tyVarKind tyvar)),
hang (ptext SLIT("Arg type:"))
- 4 (ppr arg_ty <+> ptext SLIT("::") <+> ppr (typeKind arg_ty)),
- hang (ptext SLIT("Expression:")) 4 (pprCoreExpr expr)]
+ 4 (ppr arg_ty <+> dcolon <+> ppr (typeKind arg_ty))]
-mkTyAppMsg :: FAST_STRING -> Type -> Type -> CoreExpr -> ErrMsg
-mkTyAppMsg msg ty arg expr
- = vcat [hsep [ptext msg, ptext SLIT("type application:")],
+mkTyAppMsg :: Type -> Type -> Message
+mkTyAppMsg ty arg_ty
+ = vcat [text "Illegal type application:",
hang (ptext SLIT("Exp type:"))
- 4 (ppr ty <+> ptext SLIT("::") <+> ppr (typeKind ty)),
+ 4 (ppr ty <+> dcolon <+> ppr (typeKind ty)),
hang (ptext SLIT("Arg type:"))
- 4 (ppr arg <+> ptext SLIT("::") <+> ppr (typeKind arg)),
- hang (ptext SLIT("Expression:")) 4 (pprCoreExpr expr)]
-
-mkAlgAltMsg1 :: Type -> ErrMsg
-mkAlgAltMsg1 ty
- = ($$) (text "In some case statement, type of scrutinee is not a data type:")
- (ppr ty)
+ 4 (ppr arg_ty <+> dcolon <+> ppr (typeKind arg_ty))]
-mkAlgAltMsg2 :: Type -> Id -> ErrMsg
-mkAlgAltMsg2 ty con
- = vcat [
- text "In some algebraic case alternative, constructor is not a constructor of scrutinee type:",
- ppr ty,
- ppr con
- ]
-
-mkAlgAltMsg3 :: Id -> [Id] -> ErrMsg
-mkAlgAltMsg3 con alts
- = vcat [
- text "In some algebraic case alternative, number of arguments doesn't match constructor:",
- ppr con,
- ppr alts
- ]
-
-mkAlgAltMsg4 :: Type -> Id -> ErrMsg
-mkAlgAltMsg4 ty arg
- = vcat [
- text "In some algebraic case alternative, type of argument doesn't match data constructor:",
- ppr ty,
- ppr arg
- ]
-
-mkPrimAltMsg :: (Literal, CoreExpr) -> ErrMsg
-mkPrimAltMsg alt
- = ($$)
- (text "In a primitive case alternative, type of literal doesn't match type of scrutinee:")
- (ppr alt)
-
-mkRhsMsg :: Id -> Type -> ErrMsg
+mkRhsMsg :: Id -> Type -> Message
mkRhsMsg binder ty
= vcat
[hsep [ptext SLIT("The type of this binder doesn't match the type of its RHS:"),
hsep [ptext SLIT("Binder's type:"), ppr (idType binder)],
hsep [ptext SLIT("Rhs type:"), ppr ty]]
-mkRhsPrimMsg :: Id -> CoreExpr -> ErrMsg
+mkRhsPrimMsg :: Id -> CoreExpr -> Message
mkRhsPrimMsg binder rhs
= vcat [hsep [ptext SLIT("The type of this binder is primitive:"),
ppr binder],
hsep [ptext SLIT("Binder's type:"), ppr (idType binder)]
]
+
+mkUnboxedTupleMsg :: Id -> Message
+mkUnboxedTupleMsg binder
+ = vcat [hsep [ptext SLIT("A variable has unboxed tuple type:"), ppr binder],
+ hsep [ptext SLIT("Binder's type:"), ppr (idType binder)]]
+
+mkCoerceErr from_ty expr_ty
+ = vcat [ptext SLIT("From-type of Coerce differs from type of enclosed expression"),
+ ptext SLIT("From-type:") <+> ppr from_ty,
+ ptext SLIT("Type of enclosed expr:") <+> ppr expr_ty
+ ]
+
+mkStrangeTyMsg e
+ = ptext SLIT("Type where expression expected:") <+> ppr e
\end{code}