rnImports, importsFromLocalDecls,
rnExports,
getLocalDeclBinders, extendRdrEnvRn,
- reportUnusedNames, reportDeprecations
+ reportUnusedNames, finishDeprecations
) where
#include "HsVersions.h"
import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl,
ForeignDecl(..), HsGroup(..), HsValBinds(..),
Sig(..), collectHsBindLocatedBinders, tyClDeclNames,
- instDeclATs, isIdxTyDecl,
+ instDeclATs, isFamInstDecl,
LIE )
import RnEnv
import RnHsDoc ( rnHsDoc )
import IfaceEnv ( ifaceExportNames )
-import LoadIface ( loadSrcInterface )
+import LoadIface ( loadSrcInterface, loadSysInterface )
import TcRnMonad hiding (LIE)
import PrelNames
import Name
import NameEnv
import NameSet
-import OccName ( srcDataName, pprNonVarNameSpace,
- occNameSpace,
- OccEnv, mkOccEnv, mkOccEnv_C, lookupOccEnv,
- emptyOccEnv, extendOccEnv )
-import HscTypes ( GenAvailInfo(..), AvailInfo, availNames, availName,
- HomePackageTable, PackageIfaceTable,
- mkPrintUnqualified, availsToNameSet,
- Deprecs(..), ModIface(..), Dependencies(..),
- lookupIfaceByModule, ExternalPackageState(..)
- )
-import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, Parent(..),
- GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..),
- emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts,
- extendGlobalRdrEnv, lookupGlobalRdrEnv,
- lookupGRE_RdrName, lookupGRE_Name,
- Provenance(..), ImportSpec(..), ImpDeclSpec(..), ImpItemSpec(..),
- importSpecLoc, importSpecModule, isLocalGRE, pprNameProvenance,
- unQualSpecOK, qualSpecOK )
+import OccName
+import HscTypes
+import RdrName
import Outputable
import Maybes
-import SrcLoc ( Located(..), mkGeneralSrcSpan, getLoc,
- unLoc, noLoc, srcLocSpan, SrcSpan )
+import SrcLoc
import FiniteMap
import ErrUtils
import BasicTypes ( DeprecTxt )
-- warning for {- SOURCE -} ones that are unnecessary
= do this_mod <- getModule
implicit_prelude <- doptM Opt_ImplicitPrelude
- let all_imports = mk_prel_imports this_mod implicit_prelude ++ imports
- (source, ordinary) = partition is_source_import all_imports
+ let prel_imports = mkPrelImports this_mod implicit_prelude imports
+ (source, ordinary) = partition is_source_import imports
is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot
- stuff1 <- mapM (rnImportDecl this_mod) ordinary
+ stuff1 <- mapM (rnImportDecl this_mod) (prel_imports ++ ordinary)
stuff2 <- mapM (rnImportDecl this_mod) source
let (decls, rdr_env, imp_avails) = combine (stuff1 ++ stuff2)
return (decls, rdr_env, imp_avails)
where
--- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();
--- because the former doesn't even look at Prelude.hi for instance
--- declarations, whereas the latter does.
- mk_prel_imports this_mod implicit_prelude
- | this_mod == pRELUDE
- || explicit_prelude_import
- || not implicit_prelude
- = []
- | otherwise = [preludeImportDecl]
- explicit_prelude_import
- = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- imports,
- unLoc mod == pRELUDE_NAME ]
-
combine :: [(LImportDecl Name, GlobalRdrEnv, ImportAvails)]
-> ([LImportDecl Name], GlobalRdrEnv, ImportAvails)
combine = foldr plus ([], emptyGlobalRdrEnv, emptyImportAvails)
gbl_env1 `plusGlobalRdrEnv` gbl_env2,
imp_avails1 `plusImportAvails` imp_avails2)
-preludeImportDecl :: LImportDecl RdrName
-preludeImportDecl
- = L loc $
- ImportDecl (L loc pRELUDE_NAME)
+mkPrelImports :: Module -> Bool -> [LImportDecl RdrName] -> [LImportDecl RdrName]
+-- Consruct the implicit declaration "import Prelude" (or not)
+--
+-- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();
+-- because the former doesn't even look at Prelude.hi for instance
+-- declarations, whereas the latter does.
+mkPrelImports this_mod implicit_prelude import_decls
+ | this_mod == pRELUDE
+ || explicit_prelude_import
+ || not implicit_prelude
+ = []
+ | otherwise = [preludeImportDecl]
+ where
+ explicit_prelude_import
+ = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- import_decls,
+ unLoc mod == pRELUDE_NAME ]
+
+ preludeImportDecl :: LImportDecl RdrName
+ preludeImportDecl
+ = L loc $
+ ImportDecl (L loc pRELUDE_NAME)
False {- Not a boot interface -}
False {- Not qualified -}
Nothing {- No "as" -}
Nothing {- No import list -}
- where
- loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
-
+ loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
+
rnImportDecl :: Module
-> LImportDecl RdrName
let
imp_mod = mi_module iface
deprecs = mi_deprecs iface
- is_orph = mi_orphan iface
+ orph_iface = mi_orphan iface
has_finsts = mi_finsts iface
deps = mi_deps iface
let
-- Compute new transitive dependencies
- orphans | is_orph = ASSERT( not (imp_mod `elem` dep_orphs deps) )
- imp_mod : dep_orphs deps
- | otherwise = dep_orphs deps
+ orphans | orph_iface = ASSERT( not (imp_mod `elem` dep_orphs deps) )
+ imp_mod : dep_orphs deps
+ | otherwise = dep_orphs deps
finsts | has_finsts = ASSERT( not (imp_mod `elem` dep_finsts deps) )
imp_mod : dep_finsts deps
for_hs_bndrs = [nm | L _ (ForeignImport nm _ _) <- foreign_decls]
new_tc tc_decl
- | isIdxTyDecl (unLoc tc_decl)
+ | isFamInstDecl (unLoc tc_decl)
= do { main_name <- lookupFamInstDeclBndr mod main_rdr
; sub_names <- mappM (newTopSrcBinder mod) sub_rdrs
; return (AvailTC main_name sub_names) }
-- it came from. It's illegal to export two distinct things
-- that have the same occurrence name
-rnExports :: Bool -- False => no 'module M(..) where' header at all
+rnExports :: Bool -- False => no 'module M(..) where' header at all
-> Maybe [LIE RdrName] -- Nothing => no explicit export list
- -> RnM (Maybe [LIE Name], [AvailInfo])
+ -> TcGblEnv
+ -> RnM TcGblEnv
-- Complains if two distinct exports have same OccName
-- Warns about identical exports.
-- Complains about exports items not in scope
-rnExports explicit_mod exports
- = do TcGblEnv { tcg_mod = this_mod,
- tcg_rdr_env = rdr_env,
- tcg_imports = imports } <- getGblEnv
-
+rnExports explicit_mod exports
+ tcg_env@(TcGblEnv { tcg_mod = this_mod,
+ tcg_rdr_env = rdr_env,
+ tcg_imports = imports })
+ = do {
-- If the module header is omitted altogether, then behave
-- as if the user had written "module Main(main) where..."
-- EXCEPT in interactive mode, when we behave as if he had
-- written "module Main where ..."
-- Reason: don't want to complain about 'main' not in scope
-- in interactive mode
- ghc_mode <- getGhcMode
- real_exports <-
- case () of
- () | explicit_mod
- -> return exports
- | ghc_mode == Interactive
- -> return Nothing
- | otherwise
- -> do mainName <- lookupGlobalOccRn main_RDR_Unqual
- return (Just ([noLoc (IEVar main_RDR_Unqual)]))
- -- ToDo: the 'noLoc' here is unhelpful if 'main' turns
- -- out to be out of scope
-
- (exp_spec, avails) <- exports_from_avail real_exports rdr_env imports this_mod
-
- return (exp_spec, nubAvails avails) -- Combine families
+ ; ghc_mode <- getGhcMode
+ ; let real_exports
+ | explicit_mod = exports
+ | ghc_mode == Interactive = Nothing
+ | otherwise = Just ([noLoc (IEVar main_RDR_Unqual)])
+ -- ToDo: the 'noLoc' here is unhelpful if 'main'
+ -- turns out to be out of scope
+
+ ; (rn_exports, avails) <- exports_from_avail real_exports rdr_env imports this_mod
+ ; let final_avails = nubAvails avails -- Combine families
+
+ ; return (tcg_env { tcg_exports = final_avails,
+ tcg_rn_exports = case tcg_rn_exports tcg_env of
+ Nothing -> Nothing
+ Just _ -> rn_exports,
+ tcg_dus = tcg_dus tcg_env `plusDU`
+ usesOnly (availsToNameSet final_avails) }) }
+
exports_from_avail :: Maybe [LIE RdrName]
-- Nothing => no explicit export list
return (IEVar (gre_name gre), greAvail gre)
lookup_ie (IEThingAbs rdr)
- = do name <- lookupGlobalOccRn rdr
- case lookupGRE_RdrName rdr rdr_env of
- [] -> panic "RnNames.lookup_ie"
- elt:_ -> case gre_par elt of
- NoParent -> return (IEThingAbs name,
- AvailTC name [name])
- ParentIs p -> return (IEThingAbs name,
- AvailTC p [name])
+ = do gre <- lookupGreRn rdr
+ let name = gre_name gre
+ case gre_par gre of
+ NoParent -> return (IEThingAbs name,
+ AvailTC name [name])
+ ParentIs p -> return (IEThingAbs name,
+ AvailTC p [name])
lookup_ie ie@(IEThingAll rdr)
= do name <- lookupGlobalOccRn rdr
%*********************************************************
\begin{code}
-reportDeprecations :: DynFlags -> TcGblEnv -> RnM ()
-reportDeprecations dflags tcg_env
- = ifOptM Opt_WarnDeprecations $
- do { (eps,hpt) <- getEpsAndHpt
+finishDeprecations :: DynFlags -> Maybe DeprecTxt
+ -> TcGblEnv -> RnM TcGblEnv
+-- (a) Report usasge of deprecated imports
+-- (b) If the whole module is deprecated, update tcg_deprecs
+-- All this happens only once per module
+finishDeprecations dflags mod_deprec tcg_env
+ = do { (eps,hpt) <- getEpsAndHpt
+ ; ifOptM Opt_WarnDeprecations $
+ mapM_ (check hpt (eps_PIT eps)) all_gres
-- By this time, typechecking is complete,
-- so the PIT is fully populated
- ; mapM_ (check hpt (eps_PIT eps)) all_gres }
+
+ -- Deal with a module deprecation; it overrides all existing deprecs
+ ; let new_deprecs = case mod_deprec of
+ Just txt -> DeprecAll txt
+ Nothing -> tcg_deprecs tcg_env
+ ; return (tcg_env { tcg_deprecs = new_deprecs }) }
where
used_names = allUses (tcg_dus tcg_env)
-- Report on all deprecated uses; hence allUses
check hpt pit gre@(GRE {gre_name = name, gre_prov = Imported (imp_spec:_)})
| name `elemNameSet` used_names
- , Just deprec_txt <- lookupDeprec dflags hpt pit gre
+ , Just deprec_txt <- lookupImpDeprec dflags hpt pit gre
= addWarnAt (importSpecLoc imp_spec)
(sep [ptext SLIT("Deprecated use of") <+>
pprNonVarNameSpace (occNameSpace (nameOccName name)) <+>
-- the defn of a non-deprecated thing, when changing a module's
-- interface
-lookupDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable
- -> GlobalRdrElt -> Maybe DeprecTxt
-lookupDeprec dflags hpt pit gre
+lookupImpDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable
+ -> GlobalRdrElt -> Maybe DeprecTxt
+-- The name is definitely imported, so look in HPT, PIT
+lookupImpDeprec dflags hpt pit gre
= case lookupIfaceByModule dflags hpt pit (nameModule name) of
Just iface -> mi_dep_fn iface name `seqMaybe` -- Bleat if the thing, *or
case gre_par gre of
ParentIs p -> mi_dep_fn iface p -- its parent*, is deprec'd
NoParent -> Nothing
- Nothing
- | isWiredInName name -> Nothing
- -- We have not necessarily loaded the .hi file for a
- -- wired-in name (yet), although we *could*.
- -- And we never deprecate them
-
- | otherwise -> pprPanic "lookupDeprec" (ppr name)
- -- By now all the interfaces should have been loaded
+
+ Nothing -> Nothing -- See Note [Used names with interface not loaded]
where
name = gre_name gre
\end{code}
+Note [Used names with interface not loaded]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+By now all the interfaces should have been loaded,
+because reportDeprecations happens after typechecking.
+However, it's still (just) possible to to find a used
+Name whose interface hasn't been loaded:
+
+a) It might be a WiredInName; in that case we may not load
+ its interface (although we could).
+
+b) It might be GHC.Real.fromRational, or GHC.Num.fromInteger
+ These are seen as "used" by the renamer (if -fno-implicit-prelude)
+ is on), but the typechecker may discard their uses
+ if in fact the in-scope fromRational is GHC.Read.fromRational,
+ (see tcPat.tcOverloadedLit), and the typechecker sees that the type
+ is fixed, say, to GHC.Base.Float (see Inst.lookupSimpleInst).
+ In that obscure case it won't force the interface in.
+
+In both cases we simply don't permit deprecations;
+this is, after all, wired-in stuff.
+
+
%*********************************************************
%* *
Unused names
is_unused_local :: GlobalRdrElt -> Bool
is_unused_local gre = isLocalGRE gre && isExternalName (gre_name gre)
- unused_imports :: [GlobalRdrElt]
- unused_imports = filter unused_imp defined_but_not_used
- unused_imp (GRE {gre_prov = Imported imp_specs})
- = not (all (module_unused . importSpecModule) imp_specs)
- && or [exp | ImpSpec { is_item = ImpSome { is_explicit = exp } } <- imp_specs]
- -- Don't complain about unused imports if we've already said the
- -- entire import is unused
- unused_imp other = False
+ unused_imports :: [GlobalRdrElt]
+ unused_imports = mapCatMaybes unused_imp defined_but_not_used
+ unused_imp :: GlobalRdrElt -> Maybe GlobalRdrElt -- Result has trimmed Imported provenances
+ unused_imp gre@(GRE {gre_prov = LocalDef}) = Nothing
+ unused_imp gre@(GRE {gre_prov = Imported imp_specs})
+ | null trimmed_specs = Nothing
+ | otherwise = Just (gre {gre_prov = Imported trimmed_specs})
+ where
+ trimmed_specs = filter report_if_unused imp_specs
-- To figure out the minimal set of imports, start with the things
-- that are in scope (i.e. in gbl_env). Then just combine them
--
-- BUG WARNING: does not deal correctly with multiple imports of the same module
-- becuase direct_import_mods has only one entry per module
+ unused_imp_mods :: [(ModuleName, SrcSpan)]
unused_imp_mods = [(mod_name,loc) | (mod,no_imp,loc) <- direct_import_mods,
let mod_name = moduleName mod,
not (mod_name `elemFM` minimal_imports1),
module_unused :: ModuleName -> Bool
module_unused mod = any (((==) mod) . fst) unused_imp_mods
+ report_if_unused :: ImportSpec -> Bool
+ -- Do we want to report this as an unused import?
+ report_if_unused (ImpSpec {is_decl = d, is_item = i})
+ = not (module_unused (is_mod d)) -- Not if we've already said entire import is unused
+ && isExplicitItem i -- Only if the import was explicit
+
---------------------
warnDuplicateImports :: [GlobalRdrElt] -> RnM ()
-- Given the GREs for names that are used, figure out which imports
warnDuplicateImports gres
= ifOptM Opt_WarnUnusedImports $
sequenceM_ [ warn name pr
- -- The 'head' picks the first offending group
- -- for this particular name
| GRE { gre_name = name, gre_prov = Imported imps } <- gres
, pr <- redundants imps ]
where
redundants imps
= [ (red_imp, cov_imp)
| red_imp <- imps
+ , isExplicitItem (is_item red_imp)
+ -- Complain only about redundant imports
+ -- mentioned explicitly by the user
, cov_imp <- take 1 (filter (covers red_imp) imps) ]
+ -- The 'take 1' picks the first offending group
+ -- for this particular name
-- "red_imp" is a putative redundant import
-- "cov_imp" potentially covers it
= False -- They bring into scope different qualified names
| not (is_qual red_decl) && is_qual cov_decl
= False -- Covering one doesn't bring unqualified name into scope
+ | otherwise
+ = not (isExplicitItem cov_item) -- Redundant one is selective and covering one isn't
+ || red_later -- or both are explicit; tie-break using red_later
+{-
| red_selective
= not cov_selective -- Redundant one is selective and covering one isn't
|| red_later -- Both are explicit; tie-break using red_later
= not cov_selective -- Neither import is selective
&& (is_mod red_decl == is_mod cov_decl) -- They import the same module
&& red_later -- Tie-break
+-}
where
red_loc = importSpecLoc red_imp
cov_loc = importSpecLoc cov_imp
red_later = red_loc > cov_loc
- cov_selective = selectiveImpItem cov_item
- red_selective = selectiveImpItem red_item
-
-selectiveImpItem :: ImpItemSpec -> Bool
-selectiveImpItem ImpAll = False
-selectiveImpItem (ImpSome {}) = True
-- ToDo: deal with original imports with 'qualified' and 'as M' clauses
printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports
printMinimalImports imps
= ifOptM Opt_D_dump_minimal_imports $ do {
- mod_ies <- mappM to_ies (fmToList imps) ;
+ mod_ies <- initIfaceTcRn $ mappM to_ies (fmToList imps) ;
this_mod <- getModule ;
rdr_env <- getGlobalRdrEnv ;
ioToTcRn (do { h <- openFile (mkFilename this_mod) WriteMode ;
to_ies (mod, avail_env) = do ies <- mapM to_ie (availEnvElts avail_env)
returnM (mod, ies)
- to_ie :: AvailInfo -> RnM (IE Name)
+ to_ie :: AvailInfo -> IfG (IE Name)
-- The main trick here is that if we're importing all the constructors
-- we want to say "T(..)", but if we're importing only a subset we want
-- to say "T(A,B,C)". So we have to find out what the module exports.
to_ie (AvailTC n [m]) = ASSERT( n==m )
returnM (IEThingAbs n)
to_ie (AvailTC n ns)
- = loadSrcInterface doc n_mod False `thenM` \ iface ->
+ = loadSysInterface doc n_mod `thenM` \ iface ->
case [xs | (m,as) <- mi_exports iface,
- moduleName m == n_mod,
+ m == n_mod,
AvailTC x xs <- as,
x == nameOccName n] of
[xs] | all_used xs -> returnM (IEThingAll n)
where
all_used avail_occs = all (`elem` map nameOccName ns) avail_occs
doc = text "Compute minimal imports from" <+> ppr n
- n_mod = moduleName (nameModule n)
+ n_mod = nameModule n
\end{code}
projects / ghc-hetmet.git / blobdiff