X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Frename%2FRnNames.lhs;h=8189c2a03d20d5e347018160d87f8f21c320f0a1;hp=36716763f1b1961c30b56dfcf3837f85ceda6c24;hb=1e9a92161ce58d3eb1d35b9b5f9f67e4d1bc03cf;hpb=26a4a13d5823ef77d2693c1f62ecd99634d80a88 diff --git a/compiler/rename/RnNames.lhs b/compiler/rename/RnNames.lhs index 3671676..8189c2a 100644 --- a/compiler/rename/RnNames.lhs +++ b/compiler/rename/RnNames.lhs @@ -17,12 +17,12 @@ import DynFlags ( DynFlag(..), GhcMode(..), DynFlags(..) ) 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 @@ -336,7 +336,7 @@ getLocalDeclBinders gbl_env (HsGroup {hs_valds = ValBindsIn val_decls val_sigs, 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) } @@ -918,7 +918,7 @@ reportDeprecations dflags tcg_env 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)) <+> @@ -940,26 +940,43 @@ reportDeprecations dflags tcg_env -- 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 @@ -1012,14 +1029,15 @@ reportUnusedNames export_decls gbl_env 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 @@ -1095,6 +1113,7 @@ reportUnusedNames export_decls gbl_env -- -- 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), @@ -1107,6 +1126,12 @@ reportUnusedNames export_decls gbl_env 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 @@ -1125,8 +1150,6 @@ warnDuplicateImports :: [GlobalRdrElt] -> RnM () 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 @@ -1145,7 +1168,12 @@ warnDuplicateImports gres 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 @@ -1166,6 +1194,10 @@ warnDuplicateImports gres = 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 @@ -1173,16 +1205,11 @@ warnDuplicateImports gres = 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 @@ -1190,7 +1217,7 @@ 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 ; @@ -1211,7 +1238,7 @@ printMinimalImports imps 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. @@ -1219,9 +1246,9 @@ printMinimalImports imps 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) @@ -1231,7 +1258,7 @@ printMinimalImports imps 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}