%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[RnIfaces]{Cacheing and Renaming of Interfaces}
\begin{code}
-#include "HsVersions.h"
-
module RnIfaces (
- cacheInterface,
- readInterface,
- rnInterfaces,
- finalIfaceInfo,
- IfaceCache(..),
- VersionInfo(..),
- ParsedIface(..)
- ) where
+ getInterfaceExports,
+ getImportedInstDecls, getImportedRules,
+ lookupFixity, loadHomeInterface,
+ importDecl, recordSlurp,
+ getImportVersions, getSlurped,
-import PreludeGlaST ( returnPrimIO, thenPrimIO,
- readVar, writeVar, MutableVar(..) )
+ checkUpToDate,
-import Ubiq
+ getDeclBinders
+ ) where
-import HsSyn
-import RdrHsSyn
-import RnHsSyn
+#include "HsVersions.h"
+import CmdLineOpts ( opt_NoPruneDecls, opt_IgnoreIfacePragmas )
+import HsSyn ( HsDecl(..), TyClDecl(..), InstDecl(..), IfaceSig(..),
+ HsType(..), ConDecl(..), IE(..), ConDetails(..), Sig(..),
+ FixitySig(..), RuleDecl(..),
+ isClassOpSig
+ )
+import BasicTypes ( Version, NewOrData(..), defaultFixity )
+import RdrHsSyn ( RdrNameHsDecl, RdrNameInstDecl, RdrNameTyClDecl, RdrNameRuleDecl,
+ extractHsTyRdrNames
+ )
+import RnEnv ( mkImportedGlobalName, newImportedBinder, mkImportedGlobalFromRdrName,
+ lookupOccRn,
+ pprAvail,
+ availName, availNames, addAvailToNameSet,
+ FreeVars, emptyFVs
+ )
import RnMonad
-import RnUtils ( RnEnv(..) )
+import RnHsSyn ( RenamedHsDecl )
+import ParseIface ( parseIface, IfaceStuff(..) )
+
+import FiniteMap ( FiniteMap, sizeFM, emptyFM, delFromFM,
+ lookupFM, addToFM, addToFM_C, addListToFM,
+ fmToList, elemFM, foldFM
+ )
+import Name ( Name {-instance NamedThing-},
+ nameModule, isLocallyDefined,
+ isWiredInName, nameUnique, NamedThing(..)
+ )
+import Module ( Module, moduleString, pprModule,
+ mkVanillaModule, pprModuleName,
+ moduleUserString, moduleName, isLibModule,
+ ModuleName, WhereFrom(..),
+ )
+import RdrName ( RdrName, rdrNameOcc )
+import NameSet
+import Var ( Id )
+import SrcLoc ( mkSrcLoc, SrcLoc )
+import PrelMods ( pREL_GHC )
+import PrelInfo ( cCallishTyKeys, thinAirModules )
+import Bag
+import Maybes ( MaybeErr(..), maybeToBool, orElse )
+import ListSetOps ( unionLists )
+import Outputable
+import Unique ( Unique )
+import StringBuffer ( StringBuffer, hGetStringBuffer )
+import FastString ( mkFastString )
+import Lex
+import Outputable
+
+import IO ( isDoesNotExistError )
+import List ( nub )
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Loading a new interface file}
+%* *
+%*********************************************************
+
+\begin{code}
+loadHomeInterface :: SDoc -> Name -> RnM d (Module, Ifaces)
+loadHomeInterface doc_str name
+ = loadInterface doc_str (moduleName (nameModule name)) ImportBySystem
+
+loadInterface :: SDoc -> ModuleName -> WhereFrom -> RnM d (Module, Ifaces)
+loadInterface doc_str mod_name from
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ mod_map = iImpModInfo ifaces
+ mod_info = lookupFM mod_map mod_name
+ in_map = maybeToBool mod_info
+ in
+
+ -- Issue a warning for a redundant {- SOURCE -} import
+ -- It's redundant if the moduld is in the iImpModInfo at all,
+ -- because we arrange to read all the ordinary imports before
+ -- any of the {- SOURCE -} imports
+ warnCheckRn (not (in_map && case from of {ImportByUserSource -> True; other -> False}))
+ (warnRedundantSourceImport mod_name) `thenRn_`
+
+ -- CHECK WHETHER WE HAVE IT ALREADY
+ case mod_info of {
+ Just (_, _, Just (load_mod, _, _))
+ -> -- We're read it already so don't re-read it
+ returnRn (load_mod, ifaces) ;
+
+ mod_map_result ->
+
+ -- READ THE MODULE IN
+ findAndReadIface doc_str mod_name from in_map `thenRn` \ (hi_boot_read, read_result) ->
+ case read_result of {
+ Nothing -> -- Not found, so add an empty export env to the Ifaces map
+ -- so that we don't look again
+ let
+ mod = mkVanillaModule mod_name
+ new_mod_map = addToFM mod_map mod_name (0, False, Just (mod, False, []))
+ new_ifaces = ifaces { iImpModInfo = new_mod_map }
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ failWithRn (mod, new_ifaces) (noIfaceErr mod hi_boot_read) ;
+
+ -- Found and parsed!
+ Just (mod, iface) ->
+
+ -- LOAD IT INTO Ifaces
+
+ -- NB: *first* we do loadDecl, so that the provenance of all the locally-defined
+ --- names is done correctly (notably, whether this is an .hi file or .hi-boot file).
+ -- If we do loadExport first the wrong info gets into the cache (unless we
+ -- explicitly tag each export which seems a bit of a bore)
+
+ getModuleRn `thenRn` \ this_mod_nm ->
+ let
+ rd_decls = pi_decls iface
+ in
+ foldlRn (loadDecl mod) (iDecls ifaces) rd_decls `thenRn` \ new_decls ->
+ foldlRn (loadInstDecl mod) (iInsts ifaces) (pi_insts iface) `thenRn` \ new_insts ->
+ foldlRn (loadRule mod) (iRules ifaces) (pi_rules iface) `thenRn` \ new_rules ->
+ foldlRn (loadFixDecl mod_name) (iFixes ifaces) rd_decls `thenRn` \ new_fixities ->
+ mapRn (loadExport this_mod_nm) (pi_exports iface) `thenRn` \ avails_s ->
+ let
+ -- For an explicit user import, add to mod_map info about
+ -- the things the imported module depends on, extracted
+ -- from its usage info.
+ mod_map1 = case from of
+ ImportByUser -> addModDeps mod mod_map (pi_usages iface)
+ other -> mod_map
+
+ -- Now add info about this module
+ mod_map2 = addToFM mod_map1 mod_name mod_details
+ mod_details = (pi_mod iface, pi_orphan iface, Just (mod, hi_boot_read, concat avails_s))
+
+ new_ifaces = ifaces { iImpModInfo = mod_map2,
+ iDecls = new_decls,
+ iFixes = new_fixities,
+ iRules = new_rules,
+ iInsts = new_insts }
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ returnRn (mod, new_ifaces)
+ }}
+
+addModDeps :: Module -> ImportedModuleInfo
+ -> [ImportVersion a] -> ImportedModuleInfo
+addModDeps mod mod_deps new_deps
+ = foldr add mod_deps new_deps
+ where
+ is_lib = isLibModule mod -- Don't record dependencies when importing a library module
+ add (imp_mod, version, has_orphans, _) deps
+ | is_lib && not has_orphans = deps
+ | otherwise = addToFM_C combine deps imp_mod (version, has_orphans, Nothing)
+ -- Record dependencies for modules that are
+ -- either are dependent via a non-library module
+ -- or contain orphan rules or instance decls
+
+ -- Don't ditch a module that's already loaded!!
+ combine old@(_, _, Just _) new = old
+ combine old@(_, _, Nothing) new = new
+
+loadExport :: ModuleName -> ExportItem -> RnM d [AvailInfo]
+loadExport this_mod (mod, entities)
+ | mod == this_mod = returnRn []
+ -- If the module exports anything defined in this module, just ignore it.
+ -- Reason: otherwise it looks as if there are two local definition sites
+ -- for the thing, and an error gets reported. Easiest thing is just to
+ -- filter them out up front. This situation only arises if a module
+ -- imports itself, or another module that imported it. (Necessarily,
+ -- this invoves a loop.) Consequence: if you say
+ -- module A where
+ -- import B( AType )
+ -- type AType = ...
+ --
+ -- module B( AType ) where
+ -- import {-# SOURCE #-} A( AType )
+ --
+ -- then you'll get a 'B does not export AType' message. A bit bogus
+ -- but it's a bogus thing to do!
+
+ | otherwise
+ = mapRn (load_entity mod) entities
+ where
+ new_name mod occ = mkImportedGlobalName mod occ
+
+ load_entity mod (Avail occ)
+ = new_name mod occ `thenRn` \ name ->
+ returnRn (Avail name)
+ load_entity mod (AvailTC occ occs)
+ = new_name mod occ `thenRn` \ name ->
+ mapRn (new_name mod) occs `thenRn` \ names ->
+ returnRn (AvailTC name names)
+
+
+loadFixDecl :: ModuleName -> FixityEnv
+ -> (Version, RdrNameHsDecl)
+ -> RnM d FixityEnv
+loadFixDecl mod_name fixity_env (version, FixD sig@(FixitySig rdr_name fixity loc))
+ = -- Ignore the version; when the fixity changes the version of
+ -- its 'host' entity changes, so we don't need a separate version
+ -- number for fixities
+ mkImportedGlobalName mod_name (rdrNameOcc rdr_name) `thenRn` \ name ->
+ let
+ new_fixity_env = addToNameEnv fixity_env name (FixitySig name fixity loc)
+ in
+ returnRn new_fixity_env
+
+ -- Ignore the other sorts of decl
+loadFixDecl mod_name fixity_env other_decl = returnRn fixity_env
+
+loadDecl :: Module
+ -> DeclsMap
+ -> (Version, RdrNameHsDecl)
+ -> RnM d DeclsMap
+
+loadDecl mod decls_map (version, decl)
+ = getDeclBinders new_name decl `thenRn` \ maybe_avail ->
+ case maybe_avail of {
+ Nothing -> returnRn decls_map; -- No bindings
+ Just avail ->
+
+ getDeclSysBinders new_name decl `thenRn` \ sys_bndrs ->
+ let
+ main_name = availName avail
+ new_decls_map = foldl add_decl decls_map
+ [ (name, (version, avail, name==main_name, (mod, decl')))
+ | name <- sys_bndrs ++ availNames avail]
+ add_decl decls_map (name, stuff)
+ = WARN( name `elemNameEnv` decls_map, ppr name )
+ addToNameEnv decls_map name stuff
+ in
+ returnRn new_decls_map
+ }
+ where
+ -- newImportedBinder puts into the cache the binder with the
+ -- module information set correctly. When the decl is later renamed,
+ -- the binding site will thereby get the correct module.
+ new_name rdr_name loc = newImportedBinder mod rdr_name
+
+ {-
+ If a signature decl is being loaded, and optIgnoreIfacePragmas is on,
+ we toss away unfolding information.
+
+ Also, if the signature is loaded from a module we're importing from source,
+ we do the same. This is to avoid situations when compiling a pair of mutually
+ recursive modules, peering at unfolding info in the interface file of the other,
+ e.g., you compile A, it looks at B's interface file and may as a result change
+ its interface file. Hence, B is recompiled, maybe changing its interface file,
+ which will the unfolding info used in A to become invalid. Simple way out is to
+ just ignore unfolding info.
+
+ [Jan 99: I junked the second test above. If we're importing from an hi-boot
+ file there isn't going to *be* any pragma info. Maybe the above comment
+ dates from a time where we picked up a .hi file first if it existed?]
+ -}
+ decl' = case decl of
+ SigD (IfaceSig name tp ls loc) | opt_IgnoreIfacePragmas -> SigD (IfaceSig name tp [] loc)
+ other -> decl
+
+loadInstDecl :: Module
+ -> Bag GatedDecl
+ -> RdrNameInstDecl
+ -> RnM d (Bag GatedDecl)
+loadInstDecl mod insts decl@(InstDecl inst_ty binds uprags dfun_name src_loc)
+ =
+ -- Find out what type constructors and classes are "gates" for the
+ -- instance declaration. If all these "gates" are slurped in then
+ -- we should slurp the instance decl too.
+ --
+ -- We *don't* want to count names in the context part as gates, though.
+ -- For example:
+ -- instance Foo a => Baz (T a) where ...
+ --
+ -- Here the gates are Baz and T, but *not* Foo.
+ let
+ munged_inst_ty = removeContext inst_ty
+ free_names = extractHsTyRdrNames munged_inst_ty
+ in
+ setModuleRn (moduleName mod) $
+ mapRn mkImportedGlobalFromRdrName free_names `thenRn` \ gate_names ->
+ returnRn ((mkNameSet gate_names, (mod, InstD decl)) `consBag` insts)
+
+
+-- In interface files, the instance decls now look like
+-- forall a. Foo a -> Baz (T a)
+-- so we have to strip off function argument types as well
+-- as the bit before the '=>' (which is always empty in interface files)
+removeContext (HsForAllTy tvs cxt ty) = HsForAllTy tvs [] (removeFuns ty)
+removeContext ty = removeFuns ty
+
+removeFuns (MonoFunTy _ ty) = removeFuns ty
+removeFuns ty = ty
+
+
+loadRule :: Module -> Bag GatedDecl
+ -> RdrNameRuleDecl -> RnM d (Bag GatedDecl)
+-- "Gate" the rule simply by whether the rule variable is
+-- needed. We can refine this later.
+loadRule mod rules decl@(IfaceRuleDecl var body src_loc)
+ = setModuleRn (moduleName mod) $
+ mkImportedGlobalFromRdrName var `thenRn` \ var_name ->
+ returnRn ((unitNameSet var_name, (mod, RuleD decl)) `consBag` rules)
+\end{code}
+
+
+%********************************************************
+%* *
+\subsection{Loading usage information}
+%* *
+%********************************************************
+
+\begin{code}
+checkUpToDate :: ModuleName -> RnMG Bool -- True <=> no need to recompile
+checkUpToDate mod_name
+ = getIfacesRn `thenRn` \ ifaces ->
+ findAndReadIface doc_str mod_name
+ ImportByUser
+ (error "checkUpToDate") `thenRn` \ (_, read_result) ->
+
+ -- CHECK WHETHER WE HAVE IT ALREADY
+ case read_result of
+ Nothing -> -- Old interface file not found, so we'd better bail out
+ traceRn (sep [ptext SLIT("Didnt find old iface"),
+ pprModuleName mod_name]) `thenRn_`
+ returnRn False
+
+ Just (_, iface)
+ -> -- Found it, so now check it
+ checkModUsage (pi_usages iface)
+ where
+ -- Only look in current directory, with suffix .hi
+ doc_str = sep [ptext SLIT("need usage info from"), pprModuleName mod_name]
+
+checkModUsage [] = returnRn True -- Yes! Everything is up to date!
+
+checkModUsage ((mod_name, old_mod_vers, _, whats_imported) : rest)
+ = loadInterface doc_str mod_name ImportBySystem `thenRn` \ (mod, ifaces) ->
+ let
+ maybe_mod_vers = case lookupFM (iImpModInfo ifaces) mod_name of
+ Just (version, _, Just (_, _, _)) -> Just version
+ other -> Nothing
+ in
+ case maybe_mod_vers of {
+ Nothing -> -- If we can't find a version number for the old module then
+ -- bail out saying things aren't up to date
+ traceRn (sep [ptext SLIT("Can't find version number for module"),
+ pprModuleName mod_name]) `thenRn_`
+ returnRn False ;
+
+ Just new_mod_vers ->
+
+ -- If the module version hasn't changed, just move on
+ if new_mod_vers == old_mod_vers then
+ traceRn (sep [ptext SLIT("Module version unchanged:"), pprModuleName mod_name]) `thenRn_`
+ checkModUsage rest
+ else
+ traceRn (sep [ptext SLIT("Module version has changed:"), pprModuleName mod_name]) `thenRn_`
+
+ -- Module version changed, so check entities inside
+
+ -- If the usage info wants to say "I imported everything from this module"
+ -- it does so by making whats_imported equal to Everything
+ -- In that case, we must recompile
+ case whats_imported of {
+ Everything -> traceRn (ptext SLIT("...and I needed the whole module")) `thenRn_`
+ returnRn False; -- Bale out
+
+ Specifically old_local_vers ->
+
+ -- Non-empty usage list, so check item by item
+ checkEntityUsage mod_name (iDecls ifaces) old_local_vers `thenRn` \ up_to_date ->
+ if up_to_date then
+ traceRn (ptext SLIT("...but the bits I use haven't.")) `thenRn_`
+ checkModUsage rest -- This one's ok, so check the rest
+ else
+ returnRn False -- This one failed, so just bail out now
+ }}
+ where
+ doc_str = sep [ptext SLIT("need version info for"), pprModuleName mod_name]
+
+
+checkEntityUsage mod decls []
+ = returnRn True -- Yes! All up to date!
+
+checkEntityUsage mod decls ((occ_name,old_vers) : rest)
+ = mkImportedGlobalName mod occ_name `thenRn` \ name ->
+ case lookupNameEnv decls name of
+
+ Nothing -> -- We used it before, but it ain't there now
+ putDocRn (sep [ptext SLIT("No longer exported:"), ppr name]) `thenRn_`
+ returnRn False
+
+ Just (new_vers,_,_,_) -- It's there, but is it up to date?
+ | new_vers == old_vers
+ -- Up to date, so check the rest
+ -> checkEntityUsage mod decls rest
+
+ | otherwise
+ -- Out of date, so bale out
+ -> putDocRn (sep [ptext SLIT("Out of date:"), ppr name]) `thenRn_`
+ returnRn False
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Getting in a declaration}
+%* *
+%*********************************************************
+
+\begin{code}
+importDecl :: Name -> RnMG (Maybe (Module, RdrNameHsDecl))
+ -- Returns Nothing for
+ -- (a) wired in name
+ -- (b) local decl
+ -- (c) already slurped
+
+importDecl name
+ | isWiredInName name
+ = returnRn Nothing
+ | otherwise
+ = getSlurped `thenRn` \ already_slurped ->
+ if name `elemNameSet` already_slurped then
+ returnRn Nothing -- Already dealt with
+ else
+ getModuleRn `thenRn` \ this_mod ->
+ let
+ mod = moduleName (nameModule name)
+ in
+ if mod == this_mod then -- Don't bring in decls from
+ -- the renamed module's own interface file
+ addWarnRn (importDeclWarn mod name) `thenRn_`
+ returnRn Nothing
+ else
+ getNonWiredInDecl name
+\end{code}
+
+\begin{code}
+getNonWiredInDecl :: Name -> RnMG (Maybe (Module, RdrNameHsDecl))
+getNonWiredInDecl needed_name
+ = traceRn doc_str `thenRn_`
+ loadHomeInterface doc_str needed_name `thenRn` \ (_, ifaces) ->
+ case lookupNameEnv (iDecls ifaces) needed_name of
+
+ Just (version,avail,_,decl)
+ -> recordSlurp (Just version) avail `thenRn_`
+ returnRn (Just decl)
+
+ Nothing -- Can happen legitimately for "Optional" occurrences
+ -> addErrRn (getDeclErr needed_name) `thenRn_`
+ returnRn Nothing
+ where
+ doc_str = ptext SLIT("need decl for") <+> ppr needed_name
+\end{code}
+
+@getWiredInDecl@ maps a wired-in @Name@ to what it makes available.
+It behaves exactly as if the wired in decl were actually in an interface file.
+Specifically,
-import Bag ( emptyBag )
-import ErrUtils ( Error(..), Warning(..) )
-import FiniteMap ( emptyFM, lookupFM, addToFM )
-import Pretty
-import Maybes ( MaybeErr(..) )
-import Util ( panic )
+ * if the wired-in name is a data type constructor or a data constructor,
+ it brings in the type constructor and all the data constructors; and
+ marks as "occurrences" any free vars of the data con.
+ * similarly for synonum type constructor
+
+ * if the wired-in name is another wired-in Id, it marks as "occurrences"
+ the free vars of the Id's type.
+
+ * it loads the interface file for the wired-in thing for the
+ sole purpose of making sure that its instance declarations are available
+
+All this is necessary so that we know all types that are "in play", so
+that we know just what instances to bring into scope.
+
+
+
+
+%*********************************************************
+%* *
+\subsection{Getting what a module exports}
+%* *
+%*********************************************************
+
+@getInterfaceExports@ is called only for directly-imported modules
+
+\begin{code}
+getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, Avails)
+getInterfaceExports mod_name from
+ = loadInterface doc_str mod_name from `thenRn` \ (mod, ifaces) ->
+ case lookupFM (iImpModInfo ifaces) mod_name of
+ Nothing -> -- Not there; it must be that the interface file wasn't found;
+ -- the error will have been reported already.
+ -- (Actually loadInterface should put the empty export env in there
+ -- anyway, but this does no harm.)
+ returnRn (mod, [])
+
+ Just (_, _, Just (mod, _, avails)) -> returnRn (mod, avails)
+ where
+ doc_str = sep [pprModuleName mod_name, ptext SLIT("is directly imported")]
\end{code}
+%*********************************************************
+%* *
+\subsection{Instance declarations are handled specially}
+%* *
+%*********************************************************
+
\begin{code}
-type IfaceCache = MutableVar _RealWorld (FiniteMap Module ParsedIface,
- FiniteMap Module FAST_STRING)
-
-data ParsedIface = ParsedIface
-
-
-cacheInterface :: IfaceCache -> Module
- -> PrimIO (MaybeErr ParsedIface Error)
-
-cacheInterface iface_var mod
- = readVar iface_var `thenPrimIO` \ (iface_fm, file_fm) ->
- case lookupFM iface_fm mod of
- Just iface -> returnPrimIO (Succeeded iface)
- Nothing ->
- case lookupFM file_fm mod of
- Nothing -> returnPrimIO (Failed (noIfaceErr mod))
- Just file ->
- readInterface file mod `thenPrimIO` \ read_iface ->
- case read_iface of
- Failed err -> returnPrimIO (Failed err)
- Succeeded iface ->
- let
- iface_fm' = addToFM iface_fm mod iface
- in
- writeVar iface_var (iface_fm', file_fm) `thenPrimIO` \ _ ->
- returnPrimIO (Succeeded iface)
-
-
-readInterface :: FAST_STRING -> Module
- -> PrimIO (MaybeErr ParsedIface Error)
-
-readInterface file mod = panic "readInterface"
+getImportedInstDecls :: NameSet -> RnMG [(Module,RdrNameHsDecl)]
+getImportedInstDecls gates
+ = -- First load any orphan-instance modules that aren't aready loaded
+ -- Orphan-instance modules are recorded in the module dependecnies
+ getIfacesRn `thenRn` \ ifaces ->
+ let
+ orphan_mods = [mod | (mod, (_, True, Nothing)) <- fmToList (iImpModInfo ifaces)]
+ in
+ traceRn (text "Loading orphan modules" <+> fsep (map pprModuleName orphan_mods)) `thenRn_`
+ mapRn_ load_it orphan_mods `thenRn_`
+
+ -- Now we're ready to grab the instance declarations
+ -- Find the un-gated ones and return them,
+ -- removing them from the bag kept in Ifaces
+ getIfacesRn `thenRn` \ ifaces ->
+ let
+ (decls, new_insts) = selectGated gates (iInsts ifaces)
+ in
+ setIfacesRn (ifaces { iInsts = new_insts }) `thenRn_`
+
+ traceRn (sep [text "getImportedInstDecls:",
+ nest 4 (fsep (map ppr (nameSetToList gates))),
+ text "Slurped" <+> int (length decls) <+> text "instance declarations"]) `thenRn_`
+ returnRn decls
+ where
+ load_it mod = loadInterface (doc_str mod) mod ImportBySystem
+ doc_str mod = sep [pprModuleName mod, ptext SLIT("is a orphan-instance module")]
+
+getImportedRules :: RnMG [(Module,RdrNameHsDecl)]
+getImportedRules
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ gates = iSlurp ifaces -- Anything at all that's been slurped
+ (decls, new_rules) = selectGated gates (iRules ifaces)
+ in
+ setIfacesRn (ifaces { iRules = new_rules }) `thenRn_`
+ traceRn (sep [text "getImportedRules:",
+ text "Slurped" <+> int (length decls) <+> text "rules"]) `thenRn_`
+ returnRn decls
+
+selectGated gates decl_bag
+#ifdef DEBUG
+ | opt_NoPruneDecls -- Just to try the effect of not gating at all
+ = (foldrBag (\ (_,d) ds -> d:ds) [] decl_bag, emptyBag) -- Grab them all
+
+ | otherwise
+#endif
+ = foldrBag select ([], emptyBag) decl_bag
+ where
+ select (reqd, decl) (yes, no)
+ | isEmptyNameSet (reqd `minusNameSet` gates) = (decl:yes, no)
+ | otherwise = (yes, (reqd,decl) `consBag` no)
+
+lookupFixity :: Name -> RnMS Fixity
+lookupFixity name
+ | isLocallyDefined name
+ = getFixityEnv `thenRn` \ local_fix_env ->
+ case lookupNameEnv local_fix_env name of
+ Just (FixitySig _ fix _) -> returnRn fix
+ Nothing -> returnRn defaultFixity
+
+ | otherwise -- Imported
+ = loadHomeInterface doc name `thenRn` \ (_, ifaces) ->
+ case lookupNameEnv (iFixes ifaces) name of
+ Just (FixitySig _ fix _) -> returnRn fix
+ Nothing -> returnRn defaultFixity
+ where
+ doc = ptext SLIT("Checking fixity for") <+> ppr name
\end{code}
+%*********************************************************
+%* *
+\subsection{Keeping track of what we've slurped, and version numbers}
+%* *
+%*********************************************************
+
+getImportVersions figures out what the "usage information" for this moudule is;
+that is, what it must record in its interface file as the things it uses.
+It records:
+ - anything reachable from its body code
+ - any module exported with a "module Foo".
+
+Why the latter? Because if Foo changes then this module's export list
+will change, so we must recompile this module at least as far as
+making a new interface file --- but in practice that means complete
+recompilation.
+
+What about this?
+ module A( f, g ) where module B( f ) where
+ import B( f ) f = h 3
+ g = ... h = ...
+
+Should we record B.f in A's usages? In fact we don't. Certainly, if
+anything about B.f changes than anyone who imports A should be recompiled;
+they'll get an early exit if they don't use B.f. However, even if B.f
+doesn't change at all, B.h may do so, and this change may not be reflected
+in f's version number. So there are two things going on when compiling module A:
+
+1. Are A.o and A.hi correct? Then we can bale out early.
+2. Should modules that import A be recompiled?
+
+For (1) it is slightly harmful to record B.f in A's usages, because a change in
+B.f's version will provoke full recompilation of A, producing an identical A.o,
+and A.hi differing only in its usage-version of B.f (which isn't used by any importer).
+
+For (2), because of the tricky B.h question above, we ensure that A.hi is touched
+(even if identical to its previous version) if A's recompilation was triggered by
+an imported .hi file date change. Given that, there's no need to record B.f in
+A's usages.
+
+On the other hand, if A exports "module B" then we *do* count module B among
+A's usages, because we must recompile A to ensure that A.hi changes appropriately.
+
\begin{code}
-rnInterfaces ::
- IfaceCache -- iface cache
- -> RnEnv -- original name env
- -> UniqSupply
- -> RenamedHsModule -- module to extend with iface decls
- -> [RnName] -- imported names required
- -> PrimIO (RenamedHsModule, -- extended module
- ImplicitEnv, -- implicit names required
- Bag Error,
- Bag Warning)
-
-rnInterfaces iface_var occ_env us rn_module todo
- = returnPrimIO (rn_module, (emptyFM, emptyFM), emptyBag, emptyBag)
+getImportVersions :: ModuleName -- Name of this module
+ -> Maybe [IE any] -- Export list for this module
+ -> RnMG (VersionInfo Name) -- Version info for these names
+
+getImportVersions this_mod exports
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ mod_map = iImpModInfo ifaces
+ imp_names = iVSlurp ifaces
+
+ -- mv_map groups together all the things imported from a particular module.
+ mv_map1, mv_map2 :: FiniteMap ModuleName (WhatsImported Name)
+
+ -- mv_map1 records all the modules that have a "module M"
+ -- in this module's export list with an "Everything"
+ mv_map1 = foldr add_mod emptyFM export_mods
+
+ -- mv_map2 adds the version numbers of things exported individually
+ mv_map2 = foldr add_mv mv_map1 imp_names
+
+ -- Build the result list by adding info for each module,
+ -- *omitting* (a) library modules
+ -- (b) source-imported modules
+ mk_version_info mod_name (version, has_orphans, cts) so_far
+ | omit cts = so_far -- Don't record usage info for this module
+ | otherwise = (mod_name, version, has_orphans, whats_imported) : so_far
+ where
+ whats_imported = case lookupFM mv_map2 mod_name of
+ Just wi -> wi
+ Nothing -> Specifically []
+
+ omit (Just (mod, boot_import, _)) = isLibModule mod || boot_import
+ omit Nothing = False
+ in
+ returnRn (foldFM mk_version_info [] mod_map)
+ where
+ export_mods = case exports of
+ Nothing -> []
+ Just es -> [mod | IEModuleContents mod <- es, mod /= this_mod]
+
+ add_mv v@(name, version) mv_map
+ = addToFM_C add_item mv_map mod (Specifically [v])
+ where
+ mod = moduleName (nameModule name)
+
+ add_item Everything _ = Everything
+ add_item (Specifically xs) _ = Specifically (v:xs)
+
+ add_mod mod mv_map = addToFM mv_map mod Everything
\end{code}
+\begin{code}
+getSlurped
+ = getIfacesRn `thenRn` \ ifaces ->
+ returnRn (iSlurp ifaces)
+
+recordSlurp maybe_version avail
+ = getIfacesRn `thenRn` \ ifaces@(Ifaces { iSlurp = slurped_names,
+ iVSlurp = imp_names }) ->
+ let
+ new_slurped_names = addAvailToNameSet slurped_names avail
+
+ new_imp_names = case maybe_version of
+ Just version -> (availName avail, version) : imp_names
+ Nothing -> imp_names
+ in
+ setIfacesRn (ifaces { iSlurp = new_slurped_names,
+ iVSlurp = new_imp_names })
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Getting binders out of a declaration}
+%* *
+%*********************************************************
+
+@getDeclBinders@ returns the names for a @RdrNameHsDecl@.
+It's used for both source code (from @availsFromDecl@) and interface files
+(from @loadDecl@).
+
+It doesn't deal with source-code specific things: ValD, DefD. They
+are handled by the sourc-code specific stuff in RnNames.
+
+\begin{code}
+getDeclBinders :: (RdrName -> SrcLoc -> RnM d Name) -- New-name function
+ -> RdrNameHsDecl
+ -> RnM d (Maybe AvailInfo)
+
+getDeclBinders new_name (TyClD (TyData _ _ tycon _ condecls _ _ src_loc))
+ = new_name tycon src_loc `thenRn` \ tycon_name ->
+ getConFieldNames new_name condecls `thenRn` \ sub_names ->
+ returnRn (Just (AvailTC tycon_name (tycon_name : nub sub_names)))
+ -- The "nub" is because getConFieldNames can legitimately return duplicates,
+ -- when a record declaration has the same field in multiple constructors
+
+getDeclBinders new_name (TyClD (TySynonym tycon _ _ src_loc))
+ = new_name tycon src_loc `thenRn` \ tycon_name ->
+ returnRn (Just (AvailTC tycon_name [tycon_name]))
+
+getDeclBinders new_name (TyClD (ClassDecl _ cname _ sigs _ _ _ _ _ src_loc))
+ = new_name cname src_loc `thenRn` \ class_name ->
+
+ -- Record the names for the class ops
+ let
+ -- just want class-op sigs
+ op_sigs = filter isClassOpSig sigs
+ in
+ mapRn (getClassOpNames new_name) op_sigs `thenRn` \ sub_names ->
+
+ returnRn (Just (AvailTC class_name (class_name : sub_names)))
+
+getDeclBinders new_name (SigD (IfaceSig var ty prags src_loc))
+ = new_name var src_loc `thenRn` \ var_name ->
+ returnRn (Just (Avail var_name))
+
+getDeclBinders new_name (FixD _) = returnRn Nothing
+getDeclBinders new_name (ForD _) = returnRn Nothing
+getDeclBinders new_name (DefD _) = returnRn Nothing
+getDeclBinders new_name (InstD _) = returnRn Nothing
+getDeclBinders new_name (RuleD _) = returnRn Nothing
+
+----------------
+getConFieldNames new_name (ConDecl con _ _ (RecCon fielddecls) src_loc : rest)
+ = mapRn (\n -> new_name n src_loc) (con:fields) `thenRn` \ cfs ->
+ getConFieldNames new_name rest `thenRn` \ ns ->
+ returnRn (cfs ++ ns)
+ where
+ fields = concat (map fst fielddecls)
+
+getConFieldNames new_name (ConDecl con _ _ condecl src_loc : rest)
+ = new_name con src_loc `thenRn` \ n ->
+ (case condecl of
+ NewCon _ (Just f) ->
+ new_name f src_loc `thenRn` \ new_f ->
+ returnRn [n,new_f]
+ _ -> returnRn [n]) `thenRn` \ nn ->
+ getConFieldNames new_name rest `thenRn` \ ns ->
+ returnRn (nn ++ ns)
+
+getConFieldNames new_name [] = returnRn []
+
+getClassOpNames new_name (ClassOpSig op _ _ src_loc) = new_name op src_loc
+\end{code}
+
+@getDeclSysBinders@ gets the implicit binders introduced by a decl.
+A the moment that's just the tycon and datacon that come with a class decl.
+They aren'te returned by getDeclBinders because they aren't in scope;
+but they *should* be put into the DeclsMap of this module.
+
+Note that this excludes the default-method names of a class decl,
+and the dict fun of an instance decl, because both of these have
+bindings of their own elsewhere.
+
+\begin{code}
+getDeclSysBinders new_name (TyClD (ClassDecl _ cname _ sigs _ _ tname dname snames src_loc))
+ = new_name dname src_loc `thenRn` \ datacon_name ->
+ new_name tname src_loc `thenRn` \ tycon_name ->
+ sequenceRn [new_name n src_loc | n <- snames] `thenRn` \ scsel_names ->
+ returnRn (tycon_name : datacon_name : scsel_names)
+
+getDeclSysBinders new_name other_decl
+ = returnRn []
+\end{code}
+
+%*********************************************************
+%* *
+\subsection{Reading an interface file}
+%* *
+%*********************************************************
\begin{code}
-finalIfaceInfo ::
- IfaceCache -- iface cache
- -> [RnName] -- all imported names required
- -> [Module] -- directly imported modules
- -> PrimIO (VersionInfo, -- info about version numbers
- [Module]) -- special instance modules
+findAndReadIface :: SDoc -> ModuleName -> WhereFrom
+ -> Bool -- Only relevant for SystemImport
+ -- True <=> Look for a .hi file
+ -- False <=> Look for .hi-boot file unless there's
+ -- a library .hi file
+ -> RnM d (Bool, Maybe (Module, ParsedIface))
+ -- Bool is True if the interface actually read was a .hi-boot one
+ -- Nothing <=> file not found, or unreadable, or illegible
+ -- Just x <=> successfully found and parsed
+
+findAndReadIface doc_str mod_name from hi_file
+ = traceRn trace_msg `thenRn_`
+ -- we keep two maps for interface files,
+ -- one for 'normal' ones, the other for .hi-boot files,
+ -- hence the need to signal which kind we're interested.
+
+ getHiMaps `thenRn` \ hi_maps ->
+
+ case find_path from hi_maps of
+ -- Found the file
+ (hi_boot, Just (fpath, mod)) -> traceRn (ptext SLIT("...reading from") <+> text fpath) `thenRn_`
+ readIface mod fpath `thenRn` \ result ->
+ returnRn (hi_boot, result)
+ (hi_boot, Nothing) -> traceRn (ptext SLIT("...not found")) `thenRn_`
+ returnRn (hi_boot, Nothing)
+ where
+ find_path ImportByUser (hi_map, _) = (False, lookupFM hi_map mod_name)
+ find_path ImportByUserSource (_, hiboot_map) = (True, lookupFM hiboot_map mod_name)
-type VersionInfo = [(Module, Version, [(FAST_STRING, Version)])]
+ find_path ImportBySystem (hi_map, hiboot_map)
+ | hi_file
+ = -- If the module we seek is in our dependent set,
+ -- Look for a .hi file
+ (False, lookupFM hi_map mod_name)
-finalIfaceInfo iface_var imps_reqd imp_mods
- = returnPrimIO ([], [])
+ | otherwise
+ -- Check if there's a library module of that name
+ -- If not, look for an hi-boot file
+ = case lookupFM hi_map mod_name of
+ stuff@(Just (_, mod)) | isLibModule mod -> (False, stuff)
+ other -> (True, lookupFM hiboot_map mod_name)
+
+ trace_msg = sep [hsep [ptext SLIT("Reading"),
+ ppr from,
+ ptext SLIT("interface for"),
+ pprModuleName mod_name <> semi],
+ nest 4 (ptext SLIT("reason:") <+> doc_str)]
\end{code}
+@readIface@ tries just the one file.
\begin{code}
-noIfaceErr mod sty
- = ppCat [ppStr "Could not find interface for", ppPStr mod]
+readIface :: Module -> String -> RnM d (Maybe (Module, ParsedIface))
+ -- Nothing <=> file not found, or unreadable, or illegible
+ -- Just x <=> successfully found and parsed
+readIface the_mod file_path
+ = ioToRnM (hGetStringBuffer False file_path) `thenRn` \ read_result ->
+ case read_result of
+ Right contents ->
+ case parseIface contents
+ PState{ bol = 0#, atbol = 1#,
+ context = [],
+ glasgow_exts = 1#,
+ loc = mkSrcLoc (mkFastString file_path) 1 } of
+ PFailed err -> failWithRn Nothing err
+ POk _ (PIface mod_nm iface) ->
+ warnCheckRn (mod_nm == moduleName the_mod)
+ (hsep [ ptext SLIT("Something is amiss; requested module name")
+ , pprModule the_mod
+ , ptext SLIT("differs from name found in the interface file ")
+ , pprModuleName mod_nm
+ ]) `thenRn_`
+ returnRn (Just (the_mod, iface))
+
+ Left err
+ | isDoesNotExistError err -> returnRn Nothing
+ | otherwise -> failWithRn Nothing (cannaeReadFile file_path err)
+\end{code}
+
+%*********************************************************
+%* *
+\subsection{Errors}
+%* *
+%*********************************************************
+
+\begin{code}
+noIfaceErr filename boot_file
+ = hsep [ptext SLIT("Could not find valid"), boot,
+ ptext SLIT("interface file"), quotes (pprModule filename)]
+ where
+ boot | boot_file = ptext SLIT("[boot]")
+ | otherwise = empty
+
+cannaeReadFile file err
+ = hcat [ptext SLIT("Failed in reading file: "),
+ text file,
+ ptext SLIT("; error="),
+ text (show err)]
+
+getDeclErr name
+ = ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name)
+
+getDeclWarn name loc
+ = sep [ptext SLIT("Failed to find (optional) interface decl for") <+> quotes (ppr name),
+ ptext SLIT("desired at") <+> ppr loc]
+
+importDeclWarn mod name
+ = sep [ptext SLIT("Compiler tried to import decl from interface file with same name as module."),
+ ptext SLIT("(possible cause: module name clashes with interface file already in scope.)")
+ ] $$
+ hsep [ptext SLIT("Interface:"), quotes (pprModuleName mod),
+ comma, ptext SLIT("name:"), quotes (ppr name)]
+
+warnRedundantSourceImport mod_name
+ = ptext SLIT("Unnecessary {- SOURCE -} in the import of module") <+> quotes (pprModuleName mod_name)
\end{code}