%
-% (c) The GRASP Project, Glasgow University, 1992-1996
+% (c) The GRASP Project, Glasgow University, 1992-1998
%
\section[Rename]{Renaming and dependency analysis passes}
\begin{code}
-#include "HsVersions.h"
-
module Rename ( renameModule ) where
-#if __GLASGOW_HASKELL__ <= 201
-import PreludeGlaST ( thenPrimIO )
-#else
-import GlaExts
-import IO
-#endif
-
-IMP_Ubiq()
-IMPORT_1_3(List(partition))
+#include "HsVersions.h"
import HsSyn
-import RdrHsSyn ( RdrName(..), SYN_IE(RdrNameHsModule), SYN_IE(RdrNameImportDecl) )
-import RnHsSyn ( SYN_IE(RenamedHsModule), SYN_IE(RenamedHsDecl), extractHsTyNames )
+import HsPragmas ( DataPragmas(..) )
+import RdrHsSyn ( RdrNameHsModule, RdrNameHsDecl, RdrNameDeprecation )
+import RnHsSyn ( RenamedHsModule, RenamedHsDecl,
+ extractHsTyNames, extractHsCtxtTyNames
+ )
-import CmdLineOpts ( opt_HiMap, opt_WarnNameShadowing, opt_D_show_rn_trace,
- opt_D_dump_rn, opt_D_show_rn_stats,
- opt_D_show_unused_imports, opt_PprUserLength
+import CmdLineOpts ( dopt_D_dump_rn_trace, dopt_D_dump_minimal_imports,
+ opt_D_dump_rn, opt_D_dump_rn_stats, opt_WarnDeprecations,
+ opt_WarnUnusedBinds
)
import RnMonad
import RnNames ( getGlobalNames )
-import RnSource ( rnDecl )
-import RnIfaces ( getImportedInstDecls, importDecl, getImportVersions, getSpecialInstModules,
- getDeferredDataDecls,
- mkSearchPath, getSlurpedNames, getRnStats
+import RnSource ( rnSourceDecls, rnDecl )
+import RnIfaces ( getImportedInstDecls, importDecl, mkImportExportInfo, getInterfaceExports,
+ getImportedRules, getSlurped, removeContext,
+ loadBuiltinRules, getDeferredDecls, ImportDeclResult(..)
+ )
+import RnEnv ( availName, availsToNameSet,
+ emptyAvailEnv, unitAvailEnv, availEnvElts, plusAvailEnv,
+ warnUnusedImports, warnUnusedLocalBinds, warnUnusedModules,
+ lookupOrigNames, unknownNameErr,
+ FreeVars, plusFVs, plusFV, unitFV, emptyFVs, isEmptyFVs, addOneFV
+ )
+import Module ( Module, ModuleName, WhereFrom(..),
+ moduleNameUserString, mkSearchPath, moduleName, mkThisModule
)
-import RnEnv ( availsToNameSet, addAvailToNameSet,
- addImplicitOccsRn, lookupImplicitOccRn )
-import Id ( GenId {- instance NamedThing -} )
-import Name ( Name, Provenance, ExportFlag(..), isLocallyDefined,
- NameSet(..), elemNameSet, mkNameSet, unionNameSets,
- nameSetToList, minusNameSet, NamedThing(..),
- nameModule, pprModule, pprOccName, nameOccName
+import Name ( Name, isLocallyDefined, NamedThing(..), getSrcLoc,
+ nameOccName, nameUnique, nameModule, maybeUserImportedFrom,
+ isUserImportedExplicitlyName, isUserImportedName,
+ maybeWiredInTyConName, maybeWiredInIdName,
+ isUserExportedName, toRdrName,
+ nameEnvElts, extendNameEnv
)
-import TysWiredIn ( unitTyCon, intTyCon, doubleTyCon )
-import PrelInfo ( ioTyCon_NAME, primIoTyCon_NAME )
-import TyCon ( TyCon )
-import PrelMods ( mAIN, gHC_MAIN )
-import ErrUtils ( SYN_IE(Error), SYN_IE(Warning) )
-import FiniteMap ( emptyFM, eltsFM, fmToList, addToFM, FiniteMap )
-import Pretty
-import Outputable ( Outputable(..), PprStyle(..) )
-import Util ( cmpPString, equivClasses, panic, assertPanic, pprTrace )
-#if __GLASGOW_HASKELL__ >= 202
-import UniqSupply
-#endif
+import OccName ( occNameFlavour, isValOcc )
+import Id ( idType )
+import TyCon ( isSynTyCon, getSynTyConDefn )
+import NameSet
+import TysWiredIn ( unitTyCon, intTyCon, doubleTyCon, boolTyCon )
+import PrelRules ( builtinRules )
+import PrelNames ( mAIN_Name, pREL_MAIN_Name, pRELUDE_Name,
+ ioTyCon_RDR,
+ unpackCString_RDR, unpackCStringFoldr_RDR, unpackCStringUtf8_RDR,
+ eqString_RDR
+ )
+import PrelInfo ( fractionalClassKeys, derivingOccurrences )
+import Type ( namesOfType, funTyCon )
+import ErrUtils ( printErrorsAndWarnings, dumpIfSet, ghcExit )
+import BasicTypes ( Version, initialVersion )
+import Bag ( isEmptyBag, bagToList )
+import FiniteMap ( FiniteMap, eltsFM, fmToList, emptyFM, lookupFM,
+ addToFM_C, elemFM, addToFM
+ )
+import UniqSupply ( UniqSupply )
+import UniqFM ( lookupUFM )
+import SrcLoc ( noSrcLoc )
+import Maybes ( maybeToBool, expectJust )
+import Outputable
+import IO ( openFile, IOMode(..) )
\end{code}
\begin{code}
-renameModule :: UniqSupply
- -> RdrNameHsModule
- -> IO (Maybe -- Nothing <=> everything up to date;
- -- no ned to recompile any further
- (RenamedHsModule, -- Output, after renaming
- InterfaceDetails, -- Interface; for interface file generatino
- RnNameSupply, -- Final env; for renaming derivings
- [Module]), -- Imported modules; for profiling
- Bag Error,
- Bag Warning
- )
-\end{code}
-
+type RenameResult = ( PersistentCompilerState,
+ , Module -- This module
+ , RenamedHsModule -- Renamed module
+ , Maybe ParsedIface -- The existing interface file, if any
+ , ParsedIface -- The new interface
+ , [Module]) -- Imported modules
+
+renameModule :: PersistentCompilerState -> HomeSymbolTable
+ -> RdrNameHsModule -> IO (Maybe RenameResult)
+renameModule old_pcs hst this_mod@(HsModule mod_name vers exports imports local_decls _ loc)
+ = -- Initialise the renamer monad
+ do {
+ ((maybe_rn_stuff, dump_action), msgs, new_pcs)
+ <- initRn dflags finder old_pcs hst loc (rename this_mod) ;
+
+ -- Check for warnings
+ printErrorsAndWarnings msgs ;
+
+ -- Dump any debugging output
+ dump_action ;
+
+ -- Return results
+ if not (isEmptyBag rn_errs_bag) then
+ return (old_pcs, Nothing)
+ else
+ return (new_pcs, maybe_rn_stuff)
+ }
+\end{code}
\begin{code}
-renameModule us this_mod@(HsModule mod_name vers exports imports fixities local_decls loc)
- = -- INITIALISE THE RENAMER MONAD
- initRn mod_name us (mkSearchPath opt_HiMap) loc $
-
- -- FIND THE GLOBAL NAME ENVIRONMENT
- getGlobalNames this_mod `thenRn` \ global_name_info ->
+rename :: RdrNameHsModule -> RnMG (Maybe RenameResult, IO ())
+rename this_mod@(HsModule mod_name vers exports imports local_decls mod_deprec loc)
+ = -- FIND THE GLOBAL NAME ENVIRONMENT
+ getGlobalNames this_mod `thenRn` \ maybe_stuff ->
- case global_name_info of {
+ -- CHECK FOR EARLY EXIT
+ case maybe_stuff of {
Nothing -> -- Everything is up to date; no need to recompile further
- rnStats [] `thenRn_`
- returnRn Nothing ;
+ rnDump [] [] `thenRn` \ dump_action ->
+ returnRn (Nothing, dump_action) ;
+
+ Just (gbl_env, local_gbl_env, export_avails, global_avail_env, old_iface) ->
- -- Otherwise, just carry on
- Just (export_env, rn_env, explicit_names) ->
+ -- DEAL WITH DEPRECATIONS
+ rnDeprecs local_gbl_env mod_deprec local_decls `thenRn` \ my_deprecs ->
+
+ -- DEAL WITH LOCAL FIXITIES
+ fixitiesFromLocalDecls local_gbl_env local_decls `thenRn` \ local_fixity_env ->
-- RENAME THE SOURCE
- initRnMS rn_env mod_name SourceMode (
- addImplicits mod_name `thenRn_`
- mapRn rnDecl local_decls
- ) `thenRn` \ rn_local_decls ->
+ initRnMS gbl_env local_fixity_env SourceMode (
+ rnSourceDecls local_decls
+ ) `thenRn` \ (rn_local_decls, source_fvs) ->
-- SLURP IN ALL THE NEEDED DECLARATIONS
- slurpDecls rn_local_decls `thenRn` \ rn_all_decls ->
+ implicitFVs mod_name rn_local_decls `thenRn` \ implicit_fvs ->
+ let
+ -- The export_fvs make the exported names look just as if they
+ -- occurred in the source program. For the reasoning, see the
+ -- comments with RnIfaces.getImportVersions.
+ -- We only need the 'parent name' of the avail;
+ -- that's enough to suck in the declaration.
+ export_fvs = mkNameSet (map availName export_avails)
+ real_source_fvs = source_fvs `plusFV` export_fvs
+
+ slurp_fvs = implicit_fvs `plusFV` real_source_fvs
+ -- It's important to do the "plus" this way round, so that
+ -- when compiling the prelude, locally-defined (), Bool, etc
+ -- override the implicit ones.
+ in
+ loadBuiltinRules builtinRules `thenRn_`
+ slurpImpDecls slurp_fvs `thenRn` \ rn_imp_decls ->
+ -- EXIT IF ERRORS FOUND
+ rnDump rn_imp_decls rn_local_decls `thenRn` \ dump_action ->
+ checkErrsRn `thenRn` \ no_errs_so_far ->
+ if not no_errs_so_far then
+ -- Found errors already, so exit now
+ returnRn (Nothing, dump_action)
+ else
-- GENERATE THE VERSION/USAGE INFO
- getImportVersions mod_name exports `thenRn` \ import_versions ->
- getNameSupplyRn `thenRn` \ name_supply ->
-
- -- REPORT UNUSED NAMES
- reportUnusedNames explicit_names `thenRn_`
+ mkImportExportInfo mod_name export_avails exports `thenRn` \ (my_exports, my_usages) ->
- -- GENERATE THE SPECIAL-INSTANCE MODULE LIST
- -- The "special instance" modules are those modules that contain instance
- -- declarations that contain no type constructor or class that was declared
- -- in that module.
- getSpecialInstModules `thenRn` \ imported_special_inst_mods ->
- let
- special_inst_decls = [d | InstD d@(InstDecl inst_ty _ _ _ _) <- rn_local_decls,
- all (not.isLocallyDefined) (nameSetToList (extractHsTyNames inst_ty))
- ]
- special_inst_mods | null special_inst_decls = imported_special_inst_mods
- | otherwise = mod_name : imported_special_inst_mods
- in
-
-
-- RETURN THE RENAMED MODULE
+ getNameSupplyRn `thenRn` \ name_supply ->
+ getIfacesRn `thenRn` \ ifaces ->
let
- import_mods = [mod | ImportDecl mod _ _ _ _ _ <- imports]
-
+ direct_import_mods :: [Module]
+ direct_import_mods = [m | (_, _, Just (m, _, _, _, imp, _))
+ <- eltsFM (iImpModInfo ifaces), user_import imp]
+
+ -- *don't* just pick the forward edges. It's entirely possible
+ -- that a module is only reachable via back edges.
+ user_import ImportByUser = True
+ user_import ImportByUserSource = True
+ user_import _ = False
+
+ this_module = mkThisModule mod_name
+
+ -- Export only those fixities that are for names that are
+ -- (a) defined in this module
+ -- (b) exported
+ exported_fixities
+ = [ FixitySig (toRdrName name) fixity loc
+ | FixitySig name fixity loc <- nameEnvElts local_fixity_env,
+ isUserExportedName name
+ ]
+
+ new_iface = ParsedIface { pi_mod = this_module
+ , pi_vers = initialVersion
+ , pi_orphan = any isOrphanDecl rn_local_decls
+ , pi_exports = my_exports
+ , pi_usages = my_usages
+ , pi_fixity = (initialVersion, exported_fixities)
+ , pi_deprecs = my_deprecs
+ -- These ones get filled in later
+ , pi_insts = [], pi_decls = []
+ , pi_rules = (initialVersion, [])
+ }
+
renamed_module = HsModule mod_name vers
- trashed_exports trashed_imports trashed_fixities
- rn_all_decls
+ trashed_exports trashed_imports
+ (rn_local_decls ++ rn_imp_decls)
+ mod_deprec
loc
+
+ result = (this_module, renamed_module,
+ old_iface, new_iface,
+ name_supply, local_fixity_env,
+ direct_import_mods)
in
- rnStats rn_all_decls `thenRn_`
- returnRn (Just (renamed_module,
- (import_versions, export_env, special_inst_mods),
- name_supply,
- import_mods))
- }
+
+ -- REPORT UNUSED NAMES, AND DEBUG DUMP
+ reportUnusedNames mod_name direct_import_mods
+ gbl_env global_avail_env
+ export_avails source_fvs
+ rn_imp_decls `thenRn_`
+
+ returnRn (Just result, dump_action) }
where
trashed_exports = {-trace "rnSource:trashed_exports"-} Nothing
trashed_imports = {-trace "rnSource:trashed_imports"-} []
- trashed_fixities = []
\end{code}
-@addImplicits@ forces the renamer to slurp in some things which aren't
+@implicitFVs@ forces the renamer to slurp in some things which aren't
mentioned explicitly, but which might be needed by the type checker.
\begin{code}
-addImplicits mod_name
- = addImplicitOccsRn (implicit_main ++ default_tys)
+implicitFVs mod_name decls
+ = lookupOrigNames implicit_occs `thenRn` \ implicit_names ->
+ returnRn (mkNameSet (map getName default_tycons) `plusFV`
+ implicit_names)
where
- -- Add occurrences for Int, Double, and (), because they
+ -- Add occurrences for Int, and (), because they
-- are the types to which ambigious type variables may be defaulted by
- -- the type checker; so they won't every appear explicitly.
+ -- the type checker; so they won't always appear explicitly.
-- [The () one is a GHC extension for defaulting CCall results.]
- default_tys = [getName intTyCon, getName doubleTyCon, getName unitTyCon]
+ -- ALSO: funTyCon, since it occurs implicitly everywhere!
+ -- (we don't want to be bothered with making funTyCon a
+ -- free var at every function application!)
+ -- Double is dealt with separately in getGates
+ default_tycons = [unitTyCon, funTyCon, boolTyCon, intTyCon]
-- Add occurrences for IO or PrimIO
- implicit_main | mod_name == mAIN = [ioTyCon_NAME]
- | mod_name == gHC_MAIN = [primIoTyCon_NAME]
- | otherwise = []
+ implicit_main | mod_name == mAIN_Name
+ || mod_name == pREL_MAIN_Name = [ioTyCon_RDR]
+ | otherwise = []
+
+ -- Now add extra "occurrences" for things that
+ -- the deriving mechanism, or defaulting, will later need in order to
+ -- generate code
+ implicit_occs = string_occs ++ foldr ((++) . get) implicit_main decls
+
+ -- Virtually every program has error messages in it somewhere
+ string_occs = [unpackCString_RDR, unpackCStringFoldr_RDR, unpackCStringUtf8_RDR,
+ eqString_RDR]
+
+ get (TyClD (TyData _ _ _ _ _ _ (Just deriv_classes) _ _ _ _))
+ = concat (map get_deriv deriv_classes)
+ get other = []
+
+ get_deriv cls = case lookupUFM derivingOccurrences cls of
+ Nothing -> []
+ Just occs -> occs
+\end{code}
+
+\begin{code}
+isOrphanDecl (InstD (InstDecl inst_ty _ _ _ _))
+ = not (foldNameSet ((||) . isLocallyDefined) False (extractHsTyNames (removeContext inst_ty)))
+ -- The 'removeContext' is because of
+ -- instance Foo a => Baz T where ...
+ -- The decl is an orphan if Baz and T are both not locally defined,
+ -- even if Foo *is* locally defined
+
+isOrphanDecl (RuleD (HsRule _ _ _ lhs _ _))
+ = check lhs
+ where
+ -- At the moment we just check for common LHS forms
+ -- Expand as necessary. Getting it wrong just means
+ -- more orphans than necessary
+ check (HsVar v) = not (isLocallyDefined v)
+ check (HsApp f a) = check f && check a
+ check (HsLit _) = False
+ check (HsOverLit _) = False
+ check (OpApp l o _ r) = check l && check o && check r
+ check (NegApp e _) = check e
+ check (HsPar e) = check e
+ check (SectionL e o) = check e && check o
+ check (SectionR o e) = check e && check o
+
+ check other = True -- Safe fall through
+
+isOrphanDecl other = False
\end{code}
\begin{code}
-slurpDecls decls
- = -- First of all, get all the compulsory decls
- slurp_compulsories decls `thenRn` \ decls1 ->
+dupDefaultDeclErrRn (DefaultDecl _ locn1 : dup_things)
+ = pushSrcLocRn locn1 $
+ addErrRn msg
+ where
+ msg = hang (ptext SLIT("Multiple default declarations"))
+ 4 (vcat (map pp dup_things))
+ pp (DefaultDecl _ locn) = ptext SLIT("here was another default declaration") <+> ppr locn
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Slurping declarations}
+%* *
+%*********************************************************
- -- Next get the optional ones
- closeDecls Optional decls1 `thenRn` \ decls2 ->
+\begin{code}
+-------------------------------------------------------
+slurpImpDecls source_fvs
+ = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenRn_`
+
+ -- The current slurped-set records all local things
+ getSlurped `thenRn` \ source_binders ->
+ slurpSourceRefs source_binders source_fvs `thenRn` \ (decls, needed) ->
+
+ -- Then get everything else
+ closeDecls decls needed `thenRn` \ decls1 ->
+
+ -- Finally, get any deferred data type decls
+ slurpDeferredDecls decls1 `thenRn` \ final_decls ->
+
+ returnRn final_decls
+
+-------------------------------------------------------
+slurpSourceRefs :: NameSet -- Variables defined in source
+ -> FreeVars -- Variables referenced in source
+ -> RnMG ([RenamedHsDecl],
+ FreeVars) -- Un-satisfied needs
+-- The declaration (and hence home module) of each gate has
+-- already been loaded
+
+slurpSourceRefs source_binders source_fvs
+ = go_outer [] -- Accumulating decls
+ emptyFVs -- Unsatisfied needs
+ emptyFVs -- Accumulating gates
+ (nameSetToList source_fvs) -- Things whose defn hasn't been loaded yet
+ where
+ -- The outer loop repeatedly slurps the decls for the current gates
+ -- and the instance decls
+
+ -- The outer loop is needed because consider
+ -- instance Foo a => Baz (Maybe a) where ...
+ -- It may be that @Baz@ and @Maybe@ are used in the source module,
+ -- but not @Foo@; so we need to chase @Foo@ too.
+ --
+ -- We also need to follow superclass refs. In particular, 'chasing @Foo@' must
+ -- include actually getting in Foo's class decl
+ -- class Wib a => Foo a where ..
+ -- so that its superclasses are discovered. The point is that Wib is a gate too.
+ -- We do this for tycons too, so that we look through type synonyms.
+
+ go_outer decls fvs all_gates []
+ = returnRn (decls, fvs)
+
+ go_outer decls fvs all_gates refs -- refs are not necessarily slurped yet
+ = traceRn (text "go_outer" <+> ppr refs) `thenRn_`
+ foldlRn go_inner (decls, fvs, emptyFVs) refs `thenRn` \ (decls1, fvs1, gates1) ->
+ getImportedInstDecls (all_gates `plusFV` gates1) `thenRn` \ inst_decls ->
+ rnInstDecls decls1 fvs1 gates1 inst_decls `thenRn` \ (decls2, fvs2, gates2) ->
+ go_outer decls2 fvs2 (all_gates `plusFV` gates2)
+ (nameSetToList (gates2 `minusNameSet` all_gates))
+ -- Knock out the all_gates because even if we don't slurp any new
+ -- decls we can get some apparently-new gates from wired-in names
+
+ go_inner (decls, fvs, gates) wanted_name
+ = importDecl wanted_name `thenRn` \ import_result ->
+ case import_result of
+ AlreadySlurped -> returnRn (decls, fvs, gates)
+ WiredIn -> returnRn (decls, fvs, gates `plusFV` getWiredInGates wanted_name)
+ Deferred -> returnRn (decls, fvs, gates `addOneFV` wanted_name) -- It's a type constructor
+
+ HereItIs decl -> rnIfaceDecl decl `thenRn` \ (new_decl, fvs1) ->
+ returnRn (new_decl : decls,
+ fvs1 `plusFV` fvs,
+ gates `plusFV` getGates source_fvs new_decl)
+
+rnInstDecls decls fvs gates []
+ = returnRn (decls, fvs, gates)
+rnInstDecls decls fvs gates (d:ds)
+ = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->
+ rnInstDecls (new_decl:decls)
+ (fvs1 `plusFV` fvs)
+ (gates `plusFV` getInstDeclGates new_decl)
+ ds
+\end{code}
- -- Finally get those deferred data type declarations
- getDeferredDataDecls `thenRn` \ data_decls ->
- mapRn rn_data_decl data_decls `thenRn` \ rn_data_decls ->
- -- Done
- returnRn (rn_data_decls ++ decls2)
+\begin{code}
+-------------------------------------------------------
+-- closeDecls keeps going until the free-var set is empty
+closeDecls decls needed
+ | not (isEmptyFVs needed)
+ = slurpDecls decls needed `thenRn` \ (decls1, needed1) ->
+ closeDecls decls1 needed1
+ | otherwise
+ = getImportedRules `thenRn` \ rule_decls ->
+ case rule_decls of
+ [] -> returnRn decls -- No new rules, so we are done
+ other -> rnIfaceDecls decls emptyFVs rule_decls `thenRn` \ (decls1, needed1) ->
+ closeDecls decls1 needed1
+
+
+-------------------------------------------------------
+-- Augment decls with any decls needed by needed.
+-- Return also free vars of the new decls (only)
+slurpDecls decls needed
+ = go decls emptyFVs (nameSetToList needed)
where
- -- The "slurp_compulsories" function is a loop that alternates
- -- between slurping compulsory decls and slurping the instance
- -- decls thus made relavant.
- -- We *must* loop again here. Why? Two reasons:
- -- (a) an instance decl will give rise to an unresolved dfun, whose
- -- decl we must slurp to get its version number; that's the version
- -- number for the whole instance decl. (And its unfolding might mention new
- -- unresolved names.)
- -- (b) an instance decl might give rise to a new unresolved class,
- -- whose decl we must slurp, which might let in some new instance decls,
- -- and so on. Example: instance Foo a => Baz [a] where ...
- slurp_compulsories decls
- = closeDecls Compulsory decls `thenRn` \ decls1 ->
+ go decls fvs [] = returnRn (decls, fvs)
+ go decls fvs (ref:refs) = slurpDecl decls fvs ref `thenRn` \ (decls1, fvs1) ->
+ go decls1 fvs1 refs
+
+-------------------------------------------------------
+slurpDecl decls fvs wanted_name
+ = importDecl wanted_name `thenRn` \ import_result ->
+ case import_result of
+ -- Found a declaration... rename it
+ HereItIs decl -> rnIfaceDecl decl `thenRn` \ (new_decl, fvs1) ->
+ returnRn (new_decl:decls, fvs1 `plusFV` fvs)
+
+ -- No declaration... (wired in thing, or deferred, or already slurped)
+ other -> returnRn (decls, fvs)
+
+
+-------------------------------------------------------
+rnIfaceDecls :: [RenamedHsDecl] -> FreeVars
+ -> [(Module, RdrNameHsDecl)]
+ -> RnM d ([RenamedHsDecl], FreeVars)
+rnIfaceDecls decls fvs [] = returnRn (decls, fvs)
+rnIfaceDecls decls fvs (d:ds) = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->
+ rnIfaceDecls (new_decl:decls) (fvs1 `plusFV` fvs) ds
+
+rnIfaceDecl (mod, decl) = initIfaceRnMS mod (rnDecl decl)
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Deferred declarations}
+%* *
+%*********************************************************
+
+The idea of deferred declarations is this. Suppose we have a function
+ f :: T -> Int
+ data T = T1 A | T2 B
+ data A = A1 X | A2 Y
+ data B = B1 P | B2 Q
+Then we don't want to load T and all its constructors, and all
+the types those constructors refer to, and all the types *those*
+constructors refer to, and so on. That might mean loading many more
+interface files than is really necessary. So we 'defer' loading T.
+
+But f might be strict, and the calling convention for evaluating
+values of type T depends on how many constructors T has, so
+we do need to load T, but not the full details of the type T.
+So we load the full decl for T, but only skeleton decls for A and B:
+ f :: T -> Int
+ data T = {- 2 constructors -}
+
+Whether all this is worth it is moot.
+
+\begin{code}
+slurpDeferredDecls :: [RenamedHsDecl] -> RnMG [RenamedHsDecl]
+slurpDeferredDecls decls
+ = getDeferredDecls `thenRn` \ def_decls ->
+ rnIfaceDecls decls emptyFVs (map stripDecl def_decls) `thenRn` \ (decls1, fvs) ->
+ ASSERT( isEmptyFVs fvs )
+ returnRn decls1
+
+stripDecl (mod, TyClD (TyData dt _ tc tvs _ nconstrs _ _ loc name1 name2))
+ = (mod, TyClD (TyData dt [] tc tvs [] nconstrs Nothing NoDataPragmas loc
+ name1 name2))
+ -- Nuke the context and constructors
+ -- But retain the *number* of constructors!
+ -- Also the tvs will have kinds on them.
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Extracting the `gates'}
+%* *
+%*********************************************************
+
+When we import a declaration like
+\begin{verbatim}
+ data T = T1 Wibble | T2 Wobble
+\end{verbatim}
+we don't want to treat @Wibble@ and @Wobble@ as gates
+{\em unless} @T1@, @T2@ respectively are mentioned by the user program.
+If only @T@ is mentioned
+we want only @T@ to be a gate;
+that way we don't suck in useless instance
+decls for (say) @Eq Wibble@, when they can't possibly be useful.
+
+@getGates@ takes a newly imported (and renamed) decl, and the free
+vars of the source program, and extracts from the decl the gate names.
+
+\begin{code}
+getGates source_fvs (SigD (IfaceSig _ ty _ _))
+ = extractHsTyNames ty
+
+getGates source_fvs (TyClD (ClassDecl ctxt cls tvs _ sigs _ _ _ _ ))
+ = (delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs)
+ (hsTyVarNames tvs)
+ `addOneToNameSet` cls)
+ `plusFV` maybe_double
+ where
+ get (ClassOpSig n _ ty _)
+ | n `elemNameSet` source_fvs = extractHsTyNames ty
+ | otherwise = emptyFVs
+
+ -- If we load any numeric class that doesn't have
+ -- Int as an instance, add Double to the gates.
+ -- This takes account of the fact that Double might be needed for
+ -- defaulting, but we don't want to load Double (and all its baggage)
+ -- if the more exotic classes aren't used at all.
+ maybe_double | nameUnique cls `elem` fractionalClassKeys
+ = unitFV (getName doubleTyCon)
+ | otherwise
+ = emptyFVs
+
+getGates source_fvs (TyClD (TySynonym tycon tvs ty _))
+ = delListFromNameSet (extractHsTyNames ty)
+ (hsTyVarNames tvs)
+ -- A type synonym type constructor isn't a "gate" for instance decls
+
+getGates source_fvs (TyClD (TyData _ ctxt tycon tvs cons _ _ _ _ _ _))
+ = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) cons)
+ (hsTyVarNames tvs)
+ `addOneToNameSet` tycon
+ where
+ get (ConDecl n _ tvs ctxt details _)
+ | n `elemNameSet` source_fvs
+ -- If the constructor is method, get fvs from all its fields
+ = delListFromNameSet (get_details details `plusFV`
+ extractHsCtxtTyNames ctxt)
+ (hsTyVarNames tvs)
+ get (ConDecl n _ tvs ctxt (RecCon fields) _)
+ -- Even if the constructor isn't mentioned, the fields
+ -- might be, as selectors. They can't mention existentially
+ -- bound tyvars (typechecker checks for that) so no need for
+ -- the deleteListFromNameSet part
+ = foldr (plusFV . get_field) emptyFVs fields
- -- Instance decls still pending?
- getImportedInstDecls `thenRn` \ inst_decls ->
- if null inst_decls then
- -- No, none
- returnRn decls1
- else
- -- Yes, there are some, so rename them and loop
- traceRn (sep [ptext SLIT("Slurped"), int (length inst_decls), ptext SLIT("instance decls")])
- `thenRn_`
- mapRn rn_inst_decl inst_decls `thenRn` \ new_inst_decls ->
- slurp_compulsories (new_inst_decls ++ decls1)
+ get other_con = emptyFVs
+
+ get_details (VanillaCon tys) = plusFVs (map get_bang tys)
+ get_details (InfixCon t1 t2) = get_bang t1 `plusFV` get_bang t2
+ get_details (RecCon fields) = plusFVs [get_bang t | (_, t) <- fields]
+
+ get_field (fs,t) | any (`elemNameSet` source_fvs) fs = get_bang t
+ | otherwise = emptyFVs
+
+ get_bang bty = extractHsTyNames (getBangType bty)
+
+getGates source_fvs other_decl = emptyFVs
\end{code}
+@getWiredInGates@ is just like @getGates@, but it sees a wired-in @Name@
+rather than a declaration.
+
\begin{code}
-closeDecls :: Necessity
- -> [RenamedHsDecl] -- Declarations got so far
- -> RnMG [RenamedHsDecl] -- input + extra decls slurped
- -- The monad includes a list of possibly-unresolved Names
- -- This list is empty when closeDecls returns
-
-closeDecls necessity decls
- = popOccurrenceName necessity `thenRn` \ maybe_unresolved ->
- case maybe_unresolved of
-
- -- No more unresolved names
- Nothing -> returnRn decls
-
- -- An unresolved name
- Just name
- -> -- Slurp its declaration, if any
--- traceRn (sep [ptext SLIT("Considering"), ppr PprDebug name]) `thenRn_`
- importDecl name necessity `thenRn` \ maybe_decl ->
- case maybe_decl of
-
- -- No declaration... (wired in thing or optional)
- Nothing -> closeDecls necessity decls
-
- -- Found a declaration... rename it
- Just decl -> rn_iface_decl mod_name necessity decl `thenRn` \ new_decl ->
- closeDecls necessity (new_decl : decls)
- where
- mod_name = nameModule name
-
-
-rn_iface_decl mod_name necessity decl -- Notice that the rnEnv starts empty
- = initRnMS emptyRnEnv mod_name (InterfaceMode necessity) (rnDecl decl)
-
-rn_inst_decl (mod_name,decl) = rn_iface_decl mod_name Compulsory (InstD decl)
-
-rn_data_decl (tycon_name,ty_decl) = rn_iface_decl mod_name Compulsory (TyD ty_decl)
- where
- mod_name = nameModule tycon_name
+getWiredInGates :: Name -> FreeVars
+getWiredInGates name -- No classes are wired in
+ | is_id = getWiredInGates_s (namesOfType (idType the_id))
+ | isSynTyCon the_tycon = getWiredInGates_s
+ (delListFromNameSet (namesOfType ty) (map getName tyvars))
+ | otherwise = unitFV name
+ where
+ maybe_wired_in_id = maybeWiredInIdName name
+ is_id = maybeToBool maybe_wired_in_id
+ maybe_wired_in_tycon = maybeWiredInTyConName name
+ Just the_id = maybe_wired_in_id
+ Just the_tycon = maybe_wired_in_tycon
+ (tyvars,ty) = getSynTyConDefn the_tycon
+
+getWiredInGates_s names = foldr (plusFV . getWiredInGates) emptyFVs (nameSetToList names)
\end{code}
\begin{code}
-reportUnusedNames explicit_avail_names
- | not opt_D_show_unused_imports
- = returnRn ()
+getInstDeclGates (InstD (InstDecl inst_ty _ _ _ _)) = extractHsTyNames inst_ty
+getInstDeclGates other = emptyFVs
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Fixities}
+%* *
+%*********************************************************
+
+\begin{code}
+fixitiesFromLocalDecls :: GlobalRdrEnv -> [RdrNameHsDecl] -> RnMG FixityEnv
+fixitiesFromLocalDecls gbl_env decls
+ = foldlRn getFixities emptyNameEnv decls `thenRn` \ env ->
+ traceRn (text "fixity env" <+> vcat (map ppr (nameEnvElts env))) `thenRn_`
+ returnRn env
+ where
+ getFixities :: FixityEnv -> RdrNameHsDecl -> RnMG FixityEnv
+ getFixities acc (FixD fix)
+ = fix_decl acc fix
+
+ getFixities acc (TyClD (ClassDecl _ _ _ _ sigs _ _ _ _ ))
+ = foldlRn fix_decl acc [sig | FixSig sig <- sigs]
+ -- Get fixities from class decl sigs too.
+ getFixities acc other_decl
+ = returnRn acc
+
+ fix_decl acc sig@(FixitySig rdr_name fixity loc)
+ = -- Check for fixity decl for something not declared
+ case lookupRdrEnv gbl_env rdr_name of {
+ Nothing | opt_WarnUnusedBinds
+ -> pushSrcLocRn loc (addWarnRn (unusedFixityDecl rdr_name fixity))
+ `thenRn_` returnRn acc
+ | otherwise -> returnRn acc ;
+
+ Just ((name,_):_) ->
+
+ -- Check for duplicate fixity decl
+ case lookupNameEnv acc name of {
+ Just (FixitySig _ _ loc') -> addErrRn (dupFixityDecl rdr_name loc loc')
+ `thenRn_` returnRn acc ;
+
+ Nothing -> returnRn (extendNameEnv acc name (FixitySig name fixity loc))
+ }}
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Deprecations}
+%* *
+%*********************************************************
+
+For deprecations, all we do is check that the names are in scope.
+It's only imported deprecations, dealt with in RnIfaces, that we
+gather them together.
+
+\begin{code}
+rnDeprecs :: GlobalRdrEnv -> Maybe DeprecTxt
+ -> [RdrNameHsDecl] -> RnMG [RdrNameDeprecation]
+rnDeprecs gbl_env mod_deprec decls
+ = mapRn rn_deprec deprecs `thenRn_`
+ returnRn (extra_deprec ++ deprecs)
+ where
+ deprecs = [d | DeprecD d <- decls]
+ extra_deprec = case mod_deprec of
+ Nothing -> []
+ Just txt -> [Deprecation (IEModuleContents undefined) txt noSrcLoc]
+
+ rn_deprec (Deprecation ie txt loc)
+ = pushSrcLocRn loc $
+ mapRn check (ieNames ie)
+
+ check n = case lookupRdrEnv gbl_env n of
+ Nothing -> addErrRn (unknownNameErr n)
+ Just _ -> returnRn ()
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Unused names}
+%* *
+%*********************************************************
+
+\begin{code}
+reportUnusedNames :: ModuleName -> [Module]
+ -> GlobalRdrEnv -> AvailEnv
+ -> Avails -> NameSet -> [RenamedHsDecl]
+ -> RnMG ()
+reportUnusedNames mod_name direct_import_mods
+ gbl_env avail_env
+ export_avails mentioned_names
+ imported_decls
+ = let
+ used_names = mentioned_names `unionNameSets` availsToNameSet export_avails
+
+ -- Now, a use of C implies a use of T,
+ -- if C was brought into scope by T(..) or T(C)
+ really_used_names = used_names `unionNameSets`
+ mkNameSet [ availName parent_avail
+ | sub_name <- nameSetToList used_names
+ , isValOcc (getOccName sub_name)
+
+ -- Usually, every used name will appear in avail_env, but there
+ -- is one time when it doesn't: tuples and other built in syntax. When you
+ -- write (a,b) that gives rise to a *use* of "(,)", so that the
+ -- instances will get pulled in, but the tycon "(,)" isn't actually
+ -- in scope. Hence the isValOcc filter.
+ --
+ -- Also, (-x) gives rise to an implicit use of 'negate'; similarly,
+ -- 3.5 gives rise to an implcit use of :%
+ -- hence the isUserImportedName filter on the warning
+
+ , let parent_avail
+ = case lookupNameEnv avail_env sub_name of
+ Just avail -> avail
+ Nothing -> WARN( isUserImportedName sub_name,
+ text "reportUnusedName: not in avail_env" <+>
+ ppr sub_name )
+ Avail sub_name
+
+ , case parent_avail of { AvailTC _ _ -> True; other -> False }
+ ]
+
+ defined_names, defined_but_not_used :: [(Name,Provenance)]
+ defined_names = concat (rdrEnvElts gbl_env)
+ defined_but_not_used = filter not_used defined_names
+ not_used name = not (name `elemNameSet` really_used_names)
+
+ -- Filter out the ones only defined implicitly
+ bad_locals :: [Name]
+ bad_locals = [n | (n,LocalDef) <- defined_but_not_used]
+
+ bad_imp_names :: [(Name,Provenance)]
+ bad_imp_names = [(n,p) | (n,p@(UserImport mod _ True) <- defined_but_not_used,
+ not (module_unused mod)]
+
+ deprec_used deprec_env = [ (n,txt)
+ | n <- nameSetToList mentioned_names,
+ not (isLocallyDefined n),
+ Just txt <- [lookupNameEnv deprec_env n] ]
+
+ -- inst_mods are directly-imported modules that
+ -- contain instance decl(s) that the renamer decided to suck in
+ -- It's not necessarily redundant to import such modules.
+ --
+ -- NOTE: Consider
+ -- module This
+ -- import M ()
+ --
+ -- The import M() is not *necessarily* redundant, even if
+ -- we suck in no instance decls from M (e.g. it contains
+ -- no instance decls, or This contains no code). It may be
+ -- that we import M solely to ensure that M's orphan instance
+ -- decls (or those in its imports) are visible to people who
+ -- import This. Sigh.
+ -- There's really no good way to detect this, so the error message
+ -- in RnEnv.warnUnusedModules is weakened instead
+ inst_mods = [m | InstD (InstDecl _ _ _ (Just dfun) _) <- imported_decls,
+ let m = nameModule dfun,
+ m `elem` direct_import_mods
+ ]
+
+ minimal_imports :: FiniteMap Module AvailEnv
+ minimal_imports0 = emptyFM
+ minimal_imports1 = foldNameSet add_name minimal_imports0 really_used_names
+ minimal_imports = foldr add_inst_mod minimal_imports1 inst_mods
+
+ add_name n acc = case maybeUserImportedFrom n of
+ Nothing -> acc
+ Just m -> addToFM_C plusAvailEnv acc m
+ (unitAvailEnv (mk_avail n))
+ add_inst_mod m acc
+ | m `elemFM` acc = acc -- We import something already
+ | otherwise = addToFM acc m emptyAvailEnv
+ -- Add an empty collection of imports for a module
+ -- from which we have sucked only instance decls
+
+ mk_avail n = case lookupNameEnv avail_env n of
+ Just (AvailTC m _) | n==m -> AvailTC n [n]
+ | otherwise -> AvailTC m [n,m]
+ Just avail -> Avail n
+ Nothing -> pprPanic "mk_avail" (ppr n)
+
+ -- unused_imp_mods are the directly-imported modules
+ -- that are not mentioned in minimal_imports
+ unused_imp_mods = [m | m <- direct_import_mods,
+ not (maybeToBool (lookupFM minimal_imports m)),
+ moduleName m /= pRELUDE_Name]
+
+ module_unused :: Module -> Bool
+ module_unused mod = mod `elem` unused_imp_mods
- | otherwise
- = getSlurpedNames `thenRn` \ slurped_names ->
- let
- unused = explicit_avail_names `minusNameSet` slurped_names
- (local_unused, imported_unused) = partition isLocallyDefined (nameSetToList unused)
- imports_by_module = equivClasses cmp imported_unused
- name1 `cmp` name2 = nameModule name1 `_CMP_STRING_` nameModule name2
-
- pp_imp sty = sep [text "For information: the following unqualified imports are unused:",
- nest 4 (vcat (map (pp_group sty) imports_by_module))]
- pp_group sty (n:ns) = sep [hcat [text "Module ", pprModule (PprForUser opt_PprUserLength) (nameModule n), char ':'],
- nest 4 (sep (map (pprOccName sty . nameOccName) (n:ns)))]
-
- pp_local sty = sep [text "For information: the following local top-level definitions are unused:",
- nest 4 (sep (map (pprOccName sty . nameOccName) local_unused))]
in
- (if null imported_unused
- then returnRn ()
- else addWarnRn pp_imp) `thenRn_`
-
- (if null local_unused
- then returnRn ()
- else addWarnRn pp_local)
-
-rnStats :: [RenamedHsDecl] -> RnMG ()
-rnStats all_decls
- | opt_D_show_rn_trace ||
- opt_D_show_rn_stats ||
+ warnUnusedModules unused_imp_mods `thenRn_`
+ warnUnusedLocalBinds bad_locals `thenRn_`
+ warnUnusedImports bad_imp_names `thenRn_`
+ printMinimalImports mod_name minimal_imports `thenRn_`
+ getIfacesRn `thenRn` \ ifaces ->
+ (if opt_WarnDeprecations
+ then mapRn_ warnDeprec (deprec_used (iDeprecs ifaces))
+ else returnRn ())
+
+-- ToDo: deal with original imports with 'qualified' and 'as M' clauses
+printMinimalImports mod_name imps
+ | not opt_D_dump_minimal_imports
+ = returnRn ()
+ | otherwise
+ = mapRn to_ies (fmToList imps) `thenRn` \ mod_ies ->
+ ioToRnM (do { h <- openFile filename WriteMode ;
+ printForUser h (vcat (map ppr_mod_ie mod_ies))
+ }) `thenRn_`
+ returnRn ()
+ where
+ filename = moduleNameUserString mod_name ++ ".imports"
+ ppr_mod_ie (mod_name, ies)
+ | mod_name == pRELUDE_Name
+ = empty
+ | otherwise
+ = ptext SLIT("import") <+> ppr mod_name <>
+ parens (fsep (punctuate comma (map ppr ies)))
+
+ to_ies (mod, avail_env) = mapRn to_ie (availEnvElts avail_env) `thenRn` \ ies ->
+ returnRn (moduleName mod, ies)
+
+ to_ie :: AvailInfo -> RnMG (IE Name)
+ to_ie (Avail n) = returnRn (IEVar n)
+ to_ie (AvailTC n [m]) = ASSERT( n==m )
+ returnRn (IEThingAbs n)
+ to_ie (AvailTC n ns) = getInterfaceExports (moduleName (nameModule n))
+ ImportBySystem `thenRn` \ (_, avails) ->
+ case [ms | AvailTC m ms <- avails, m == n] of
+ [ms] | all (`elem` ns) ms -> returnRn (IEThingAll n)
+ | otherwise -> returnRn (IEThingWith n (filter (/= n) ns))
+ other -> pprTrace "to_ie" (ppr n <+> ppr (nameModule n) <+> ppr other) $
+ returnRn (IEVar n)
+
+rnDump :: [RenamedHsDecl] -- Renamed imported decls
+ -> [RenamedHsDecl] -- Renamed local decls
+ -> RnMG (IO ())
+rnDump imp_decls local_decls
+ | opt_D_dump_rn_trace ||
+ opt_D_dump_rn_stats ||
opt_D_dump_rn
- = getRnStats all_decls `thenRn` \ msg ->
- ioToRnMG (hPutStr stderr (show msg) >>
- hPutStr stderr "\n") `thenRn_`
- returnRn ()
+ = getRnStats imp_decls `thenRn` \ stats_msg ->
- | otherwise = returnRn ()
+ returnRn (printErrs stats_msg >>
+ dumpIfSet opt_D_dump_rn "Renamer:"
+ (vcat (map ppr (local_decls ++ imp_decls))))
+
+ | otherwise = returnRn (return ())
\end{code}
+
+%*********************************************************
+%* *
+\subsection{Statistics}
+%* *
+%*********************************************************
+
+\begin{code}
+getRnStats :: [RenamedHsDecl] -> RnMG SDoc
+getRnStats imported_decls
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ n_mods = length [() | (_, _, Just _) <- eltsFM (iImpModInfo ifaces)]
+
+ decls_read = [decl | (_, avail, True, (_,decl)) <- nameEnvElts (iDecls ifaces),
+ -- Data, newtype, and class decls are in the decls_fm
+ -- under multiple names; the tycon/class, and each
+ -- constructor/class op too.
+ -- The 'True' selects just the 'main' decl
+ not (isLocallyDefined (availName avail))
+ ]
+
+ (cd_rd, dd_rd, nd_rd, sd_rd, vd_rd, _) = count_decls decls_read
+ (cd_sp, dd_sp, nd_sp, sd_sp, vd_sp, id_sp) = count_decls imported_decls
+
+ unslurped_insts = iInsts ifaces
+ inst_decls_unslurped = length (bagToList unslurped_insts)
+ inst_decls_read = id_sp + inst_decls_unslurped
+
+ stats = vcat
+ [int n_mods <+> text "interfaces read",
+ hsep [ int cd_sp, text "class decls imported, out of",
+ int cd_rd, text "read"],
+ hsep [ int dd_sp, text "data decls imported, out of",
+ int dd_rd, text "read"],
+ hsep [ int nd_sp, text "newtype decls imported, out of",
+ int nd_rd, text "read"],
+ hsep [int sd_sp, text "type synonym decls imported, out of",
+ int sd_rd, text "read"],
+ hsep [int vd_sp, text "value signatures imported, out of",
+ int vd_rd, text "read"],
+ hsep [int id_sp, text "instance decls imported, out of",
+ int inst_decls_read, text "read"],
+ text "cls dcls slurp" <+> fsep (map (ppr . tyClDeclName)
+ [d | TyClD d <- imported_decls, isClassDecl d]),
+ text "cls dcls read" <+> fsep (map (ppr . tyClDeclName)
+ [d | TyClD d <- decls_read, isClassDecl d])]
+ in
+ returnRn (hcat [text "Renamer stats: ", stats])
+
+count_decls decls
+ = (class_decls,
+ data_decls,
+ newtype_decls,
+ syn_decls,
+ val_decls,
+ inst_decls)
+ where
+ tycl_decls = [d | TyClD d <- decls]
+ (class_decls, data_decls, newtype_decls, syn_decls) = countTyClDecls tycl_decls
+
+ val_decls = length [() | SigD _ <- decls]
+ inst_decls = length [() | InstD _ <- decls]
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{Errors and warnings}
+%* *
+%************************************************************************
+
+\begin{code}
+warnDeprec :: (Name, DeprecTxt) -> RnM d ()
+warnDeprec (name, txt)
+ = pushSrcLocRn (getSrcLoc name) $
+ addWarnRn $
+ sep [ text (occNameFlavour (nameOccName name)) <+> ppr name <+>
+ text "is deprecated:", nest 4 (ppr txt) ]
+
+
+unusedFixityDecl rdr_name fixity
+ = hsep [ptext SLIT("Unused fixity declaration for"), quotes (ppr rdr_name)]
+
+dupFixityDecl rdr_name loc1 loc2
+ = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name),
+ ptext SLIT("at ") <+> ppr loc1,
+ ptext SLIT("and") <+> ppr loc2]
+\end{code}
projects / ghc-hetmet.git / blobdiff