2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
6 Loading interface files
10 loadInterface, loadInterfaceForName, loadWiredInHomeIface,
11 loadSrcInterface, loadSysInterface, loadOrphanModules,
12 findAndReadIface, readIface, -- Used when reading the module's old interface
13 loadDecls, -- Should move to TcIface and be renamed
14 initExternalPackageState,
16 ifaceStats, pprModIface, showIface
19 #include "HsVersions.h"
21 import {-# SOURCE #-} TcIface( tcIfaceDecl, tcIfaceRules, tcIfaceInst,
22 tcIfaceFamInst, tcIfaceVectInfo )
29 import BasicTypes hiding (SuccessFlag(..))
60 %************************************************************************
62 loadSrcInterface, loadOrphanModules, loadHomeInterface
64 These three are called from TcM-land
66 %************************************************************************
69 -- | Load the interface corresponding to an @import@ directive in
70 -- source code. On a failure, fail in the monad with an error message.
71 loadSrcInterface :: SDoc -> ModuleName -> IsBootInterface -> RnM ModIface
72 loadSrcInterface doc mod want_boot = do
73 -- We must first find which Module this import refers to. This involves
74 -- calling the Finder, which as a side effect will search the filesystem
75 -- and create a ModLocation. If successful, loadIface will read the
76 -- interface; it will call the Finder again, but the ModLocation will be
77 -- cached from the first search.
79 res <- ioToIOEnv $ findImportedModule hsc_env mod Nothing
82 mb_iface <- initIfaceTcRn $ loadInterface doc mod (ImportByUser want_boot)
84 Failed err -> failWithTc err
85 Succeeded iface -> return iface
87 let dflags = hsc_dflags hsc_env in
88 failWithTc (cannotFindInterface dflags mod err)
90 -- | Load interfaces for a collection of orphan modules.
91 loadOrphanModules :: [Module] -- the modules
92 -> Bool -- these are family instance-modules
94 loadOrphanModules mods isFamInstMod
95 | null mods = returnM ()
96 | otherwise = initIfaceTcRn $
97 do { traceIf (text "Loading orphan modules:" <+>
102 load mod = loadSysInterface (mk_doc mod) mod
104 | isFamInstMod = ppr mod <+> ptext SLIT("is a family-instance module")
105 | otherwise = ppr mod <+> ptext SLIT("is a orphan-instance module")
107 -- | Loads the interface for a given Name.
108 loadInterfaceForName :: SDoc -> Name -> TcRn ModIface
109 loadInterfaceForName doc name
112 -- Should not be called with a name from the module being compiled
113 this_mod <- getModule
114 ; ASSERT2( not (nameIsLocalOrFrom this_mod name), ppr name <+> parens doc )
116 initIfaceTcRn $ loadSysInterface doc (nameModule name)
119 -- | An 'IfM' function to load the home interface for a wired-in thing,
120 -- so that we're sure that we see its instance declarations and rules
121 loadWiredInHomeIface :: Name -> IfM lcl ()
122 loadWiredInHomeIface name
123 = ASSERT( isWiredInName name )
124 do loadSysInterface doc (nameModule name); return ()
126 doc = ptext SLIT("Need home interface for wired-in thing") <+> ppr name
128 -- | A wrapper for 'loadInterface' that throws an exception if it fails
129 loadSysInterface :: SDoc -> Module -> IfM lcl ModIface
130 loadSysInterface doc mod_name
131 = do { mb_iface <- loadInterface doc mod_name ImportBySystem
133 Failed err -> ghcError (ProgramError (showSDoc err))
134 Succeeded iface -> return iface }
138 %*********************************************************
142 The main function to load an interface
143 for an imported module, and put it in
144 the External Package State
146 %*********************************************************
149 loadInterface :: SDoc -> Module -> WhereFrom
150 -> IfM lcl (MaybeErr Message ModIface)
152 -- loadInterface looks in both the HPT and PIT for the required interface
153 -- If not found, it loads it, and puts it in the PIT (always).
155 -- If it can't find a suitable interface file, we
156 -- a) modify the PackageIfaceTable to have an empty entry
157 -- (to avoid repeated complaints)
158 -- b) return (Left message)
160 -- It's not necessarily an error for there not to be an interface
161 -- file -- perhaps the module has changed, and that interface
164 loadInterface doc_str mod from
165 = do { -- Read the state
166 (eps,hpt) <- getEpsAndHpt
168 ; traceIf (text "Considering whether to load" <+> ppr mod <+> ppr from)
170 -- Check whether we have the interface already
172 ; case lookupIfaceByModule dflags hpt (eps_PIT eps) mod of {
174 -> returnM (Succeeded iface) ; -- Already loaded
175 -- The (src_imp == mi_boot iface) test checks that the already-loaded
176 -- interface isn't a boot iface. This can conceivably happen,
177 -- if an earlier import had a before we got to real imports. I think.
180 let { hi_boot_file = case from of
181 ImportByUser usr_boot -> usr_boot
182 ImportBySystem -> sys_boot
184 ; mb_dep = lookupUFM (eps_is_boot eps) (moduleName mod)
185 ; sys_boot = case mb_dep of
186 Just (_, is_boot) -> is_boot
188 -- The boot-ness of the requested interface,
189 } -- based on the dependencies in directly-imported modules
191 -- READ THE MODULE IN
192 ; read_result <- findAndReadIface doc_str mod hi_boot_file
193 ; case read_result of {
195 { let fake_iface = emptyModIface mod
197 ; updateEps_ $ \eps ->
198 eps { eps_PIT = extendModuleEnv (eps_PIT eps) (mi_module fake_iface) fake_iface }
199 -- Not found, so add an empty iface to
200 -- the EPS map so that we don't look again
202 ; returnM (Failed err) } ;
205 Succeeded (iface, file_path) -- Sanity check:
206 | ImportBySystem <- from, -- system-importing...
207 modulePackageId (mi_module iface) == thisPackage dflags,
208 -- a home-package module...
209 Nothing <- mb_dep -- that we know nothing about
210 -> returnM (Failed (badDepMsg mod))
215 loc_doc = text file_path
217 initIfaceLcl mod loc_doc $ do
219 -- Load the new ModIface into the External Package State
220 -- Even home-package interfaces loaded by loadInterface
221 -- (which only happens in OneShot mode; in Batch/Interactive
222 -- mode, home-package modules are loaded one by one into the HPT)
223 -- are put in the EPS.
225 -- The main thing is to add the ModIface to the PIT, but
227 -- IfaceDecls, IfaceInst, IfaceFamInst, IfaceRules, IfaceVectInfo
228 -- out of the ModIface and put them into the big EPS pools
230 -- NB: *first* we do loadDecl, so that the provenance of all the locally-defined
231 --- names is done correctly (notably, whether this is an .hi file or .hi-boot file).
232 -- If we do loadExport first the wrong info gets into the cache (unless we
233 -- explicitly tag each export which seems a bit of a bore)
235 ; ignore_prags <- doptM Opt_IgnoreInterfacePragmas
236 ; new_eps_decls <- loadDecls ignore_prags (mi_decls iface)
237 ; new_eps_insts <- mapM tcIfaceInst (mi_insts iface)
238 ; new_eps_fam_insts <- mapM tcIfaceFamInst (mi_fam_insts iface)
239 ; new_eps_rules <- tcIfaceRules ignore_prags (mi_rules iface)
240 ; new_eps_vect_info <- tcIfaceVectInfo mod (mkNameEnv new_eps_decls)
243 ; let { final_iface = iface {
244 mi_decls = panic "No mi_decls in PIT",
245 mi_insts = panic "No mi_insts in PIT",
246 mi_fam_insts = panic "No mi_fam_insts in PIT",
247 mi_rules = panic "No mi_rules in PIT"
251 ; updateEps_ $ \ eps ->
253 eps_PIT = extendModuleEnv (eps_PIT eps) mod final_iface,
254 eps_PTE = addDeclsToPTE (eps_PTE eps) new_eps_decls,
255 eps_rule_base = extendRuleBaseList (eps_rule_base eps)
257 eps_inst_env = extendInstEnvList (eps_inst_env eps)
259 eps_fam_inst_env = extendFamInstEnvList (eps_fam_inst_env eps)
261 eps_vect_info = plusVectInfo (eps_vect_info eps)
266 extendFamInstEnvList emptyFamInstEnv
269 extendModuleEnv (eps_mod_fam_inst_env eps)
272 eps_stats = addEpsInStats (eps_stats eps)
273 (length new_eps_decls)
274 (length new_eps_insts) (length new_eps_rules) }
276 ; return (Succeeded final_iface)
280 = hang (ptext SLIT("Interface file inconsistency:"))
281 2 (sep [ptext SLIT("home-package module") <+> quotes (ppr mod) <+> ptext SLIT("is mentioned is needed,"),
282 ptext SLIT("but is not among the dependencies of interfaces directly imported by the module being compiled")])
284 -----------------------------------------------------
285 -- Loading type/class/value decls
286 -- We pass the full Module name here, replete with
287 -- its package info, so that we can build a Name for
288 -- each binder with the right package info in it
289 -- All subsequent lookups, including crucially lookups during typechecking
290 -- the declaration itself, will find the fully-glorious Name
292 -- We handle ATs specially. They are not main declarations, but also not
293 -- implict things (in particular, adding them to `implicitTyThings' would mess
294 -- things up in the renaming/type checking of source programs).
295 -----------------------------------------------------
297 addDeclsToPTE :: PackageTypeEnv -> [(Name,TyThing)] -> PackageTypeEnv
298 addDeclsToPTE pte things = extendNameEnvList pte things
301 -> [(Version, IfaceDecl)]
302 -> IfL [(Name,TyThing)]
303 loadDecls ignore_prags ver_decls
304 = do { mod <- getIfModule
305 ; thingss <- mapM (loadDecl ignore_prags mod) ver_decls
306 ; return (concat thingss)
309 loadDecl :: Bool -- Don't load pragmas into the decl pool
311 -> (Version, IfaceDecl)
312 -> IfL [(Name,TyThing)] -- The list can be poked eagerly, but the
313 -- TyThings are forkM'd thunks
314 loadDecl ignore_prags mod (_version, decl)
315 = do { -- Populate the name cache with final versions of all
316 -- the names associated with the decl
317 main_name <- mk_new_bndr mod (ifName decl)
318 -- ; traceIf (text "Loading decl for " <> ppr main_name)
319 ; implicit_names <- mapM (mk_new_bndr mod) (ifaceDeclSubBndrs decl)
321 -- Typecheck the thing, lazily
322 -- NB. Firstly, the laziness is there in case we never need the
323 -- declaration (in one-shot mode), and secondly it is there so that
324 -- we don't look up the occurrence of a name before calling mk_new_bndr
325 -- on the binder. This is important because we must get the right name
326 -- which includes its nameParent.
328 ; thing <- forkM doc $ do { bumpDeclStats main_name
329 ; tcIfaceDecl ignore_prags decl }
331 -- Populate the type environment with the implicitTyThings too.
333 -- Note [Tricky iface loop]
334 -- ~~~~~~~~~~~~~~~~~~~~~~~~
335 -- The delicate point here is that 'mini-env' should be
336 -- buildable from 'thing' without demanding any of the things 'forkM'd
337 -- by tcIfaceDecl. For example
338 -- class C a where { data T a; op :: T a -> Int }
339 -- We return the bindings
340 -- [("C", <cls>), ("T", lookup env "T"), ("op", lookup env "op")]
341 -- The call (lookup env "T") must return the tycon T without first demanding
342 -- op; because getting the latter will look up T, hence loop.
344 -- Of course, there is no reason in principle why (lookup env "T") should demand
345 -- anything do to with op, but take care:
346 -- (a) implicitTyThings, and
347 -- (b) getOccName of all the things returned by implicitThings,
348 -- must not depend on any of the nested type-checks
350 -- All a bit too finely-balanced for my liking.
352 ; let mini_env = mkOccEnv [(getOccName t, t) | t <- implicitTyThings thing]
353 lookup n = case lookupOccEnv mini_env (getOccName n) of
356 pprPanic "loadDecl" (ppr main_name <+> ppr n $$ ppr (decl))
358 ; returnM $ (main_name, thing) : [(n, lookup n) | n <- implicit_names]
360 -- We build a list from the *known* names, with (lookup n) thunks
361 -- as the TyThings. That way we can extend the PTE without poking the
364 -- mk_new_bndr allocates in the name cache the final canonical
365 -- name for the thing, with the correct
368 -- imported name, to fix the module correctly in the cache
370 = newGlobalBinder mod occ (importedSrcSpan (moduleNameFS (moduleName mod)))
371 -- ToDo: qualify with the package name if necessary
373 doc = ptext SLIT("Declaration for") <+> ppr (ifName decl)
375 bumpDeclStats :: Name -> IfL () -- Record that one more declaration has actually been used
377 = do { traceIf (text "Loading decl for" <+> ppr name)
378 ; updateEps_ (\eps -> let stats = eps_stats eps
379 in eps { eps_stats = stats { n_decls_out = n_decls_out stats + 1 } })
384 %*********************************************************
386 \subsection{Reading an interface file}
388 %*********************************************************
391 findAndReadIface :: SDoc -> Module
392 -> IsBootInterface -- True <=> Look for a .hi-boot file
393 -- False <=> Look for .hi file
394 -> TcRnIf gbl lcl (MaybeErr Message (ModIface, FilePath))
395 -- Nothing <=> file not found, or unreadable, or illegible
396 -- Just x <=> successfully found and parsed
398 -- It *doesn't* add an error to the monad, because
399 -- sometimes it's ok to fail... see notes with loadInterface
401 findAndReadIface doc_str mod hi_boot_file
402 = do { traceIf (sep [hsep [ptext SLIT("Reading"),
404 then ptext SLIT("[boot]")
406 ptext SLIT("interface for"),
408 nest 4 (ptext SLIT("reason:") <+> doc_str)])
410 -- Check for GHC.Prim, and return its static interface
413 then returnM (Succeeded (ghcPrimIface,
414 "<built in interface for GHC.Prim>"))
418 ; hsc_env <- getTopEnv
419 ; mb_found <- ioToIOEnv (findExactModule hsc_env mod)
422 err | notFound err -> do
423 { traceIf (ptext SLIT("...not found"))
425 ; returnM (Failed (cannotFindInterface dflags
426 (moduleName mod) err)) } ;
429 -- Found file, so read it
430 { let { file_path = addBootSuffix_maybe hi_boot_file (ml_hi_file loc) }
432 ; if thisPackage dflags == modulePackageId mod
433 && not (isOneShot (ghcMode dflags))
434 then returnM (Failed (homeModError mod loc))
437 ; traceIf (ptext SLIT("readIFace") <+> text file_path)
438 ; read_result <- readIface mod file_path hi_boot_file
439 ; case read_result of
440 Failed err -> returnM (Failed (badIfaceFile file_path err))
442 | mi_module iface /= mod ->
443 return (Failed (wrongIfaceModErr iface mod file_path))
445 returnM (Succeeded (iface, file_path))
446 -- Don't forget to fill in the package name...
449 notFound (Found _ _) = False
453 @readIface@ tries just the one file.
456 readIface :: Module -> FilePath -> IsBootInterface
457 -> TcRnIf gbl lcl (MaybeErr Message ModIface)
458 -- Failed err <=> file not found, or unreadable, or illegible
459 -- Succeeded iface <=> successfully found and parsed
461 readIface wanted_mod file_path is_hi_boot_file
462 = do { dflags <- getDOpts
463 ; res <- tryMostM $ readBinIface file_path
466 | wanted_mod == actual_mod -> return (Succeeded iface)
467 | otherwise -> return (Failed err)
469 actual_mod = mi_module iface
470 err = hiModuleNameMismatchWarn wanted_mod actual_mod
472 Left exn -> return (Failed (text (showException exn)))
477 %*********************************************************
479 Wired-in interface for GHC.Prim
481 %*********************************************************
484 initExternalPackageState :: ExternalPackageState
485 initExternalPackageState
487 eps_is_boot = emptyUFM,
488 eps_PIT = emptyPackageIfaceTable,
489 eps_PTE = emptyTypeEnv,
490 eps_inst_env = emptyInstEnv,
491 eps_fam_inst_env = emptyFamInstEnv,
492 eps_rule_base = mkRuleBase builtinRules,
493 -- Initialise the EPS rule pool with the built-in rules
496 eps_vect_info = noVectInfo,
497 eps_stats = EpsStats { n_ifaces_in = 0, n_decls_in = 0, n_decls_out = 0
498 , n_insts_in = 0, n_insts_out = 0
499 , n_rules_in = length builtinRules, n_rules_out = 0 }
504 %*********************************************************
506 Wired-in interface for GHC.Prim
508 %*********************************************************
511 ghcPrimIface :: ModIface
513 = (emptyModIface gHC_PRIM) {
514 mi_exports = [(gHC_PRIM, ghcPrimExports)],
516 mi_fixities = fixities,
517 mi_fix_fn = mkIfaceFixCache fixities
520 fixities = [(getOccName seqId, Fixity 0 InfixR)]
524 %*********************************************************
526 \subsection{Statistics}
528 %*********************************************************
531 ifaceStats :: ExternalPackageState -> SDoc
533 = hcat [text "Renamer stats: ", msg]
535 stats = eps_stats eps
537 [int (n_ifaces_in stats) <+> text "interfaces read",
538 hsep [ int (n_decls_out stats), text "type/class/variable imported, out of",
539 int (n_decls_in stats), text "read"],
540 hsep [ int (n_insts_out stats), text "instance decls imported, out of",
541 int (n_insts_in stats), text "read"],
542 hsep [ int (n_rules_out stats), text "rule decls imported, out of",
543 int (n_rules_in stats), text "read"]
548 %************************************************************************
552 %************************************************************************
555 -- | Read binary interface, and print it out
556 showIface :: HscEnv -> FilePath -> IO ()
557 showIface hsc_env filename = do
558 -- skip the version check; we don't want to worry about profiled vs.
559 -- non-profiled interfaces, for example.
560 writeIORef v_IgnoreHiWay True
561 iface <- initTcRnIf 's' hsc_env () () $ readBinIface filename
562 printDump (pprModIface iface)
566 pprModIface :: ModIface -> SDoc
569 = vcat [ ptext SLIT("interface")
570 <+> ppr (mi_module iface) <+> pp_boot
571 <+> ppr (mi_mod_vers iface) <+> pp_sub_vers
572 <+> (if mi_orphan iface then ptext SLIT("[orphan module]") else empty)
573 <+> (if mi_finsts iface then ptext SLIT("[family instance module]") else empty)
574 <+> integer opt_HiVersion
575 <+> ptext SLIT("where")
576 , vcat (map pprExport (mi_exports iface))
577 , pprDeps (mi_deps iface)
578 , vcat (map pprUsage (mi_usages iface))
579 , pprFixities (mi_fixities iface)
580 , vcat (map pprIfaceDecl (mi_decls iface))
581 , vcat (map ppr (mi_insts iface))
582 , vcat (map ppr (mi_fam_insts iface))
583 , vcat (map ppr (mi_rules iface))
584 , pprVectInfo (mi_vect_info iface)
585 , pprDeprecs (mi_deprecs iface)
588 pp_boot | mi_boot iface = ptext SLIT("[boot]")
591 exp_vers = mi_exp_vers iface
592 rule_vers = mi_rule_vers iface
594 pp_sub_vers | exp_vers == initialVersion && rule_vers == initialVersion = empty
595 | otherwise = brackets (ppr exp_vers <+> ppr rule_vers)
598 When printing export lists, we print like this:
600 AvailTC C [C, x, y] C(x,y)
601 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
604 pprExport :: IfaceExport -> SDoc
605 pprExport (mod, items)
606 = hsep [ ptext SLIT("export"), ppr mod, hsep (map pp_avail items) ]
608 pp_avail :: GenAvailInfo OccName -> SDoc
609 pp_avail (Avail occ) = ppr occ
610 pp_avail (AvailTC _ []) = empty
611 pp_avail (AvailTC n (n':ns))
612 | n==n' = ppr n <> pp_export ns
613 | otherwise = ppr n <> char '|' <> pp_export (n':ns)
616 pp_export names = braces (hsep (map ppr names))
618 pprUsage :: Usage -> SDoc
620 = hsep [ptext SLIT("import"), ppr (usg_name usage),
622 pp_export_version (usg_exports usage),
623 int (usg_rules usage),
624 pp_versions (usg_entities usage) ]
626 pp_versions nvs = hsep [ ppr n <+> int v | (n,v) <- nvs ]
627 pp_export_version Nothing = empty
628 pp_export_version (Just v) = int v
630 pprDeps :: Dependencies -> SDoc
631 pprDeps (Deps { dep_mods = mods, dep_pkgs = pkgs, dep_orphs = orphs,
632 dep_finsts = finsts })
633 = vcat [ptext SLIT("module dependencies:") <+> fsep (map ppr_mod mods),
634 ptext SLIT("package dependencies:") <+> fsep (map ppr pkgs),
635 ptext SLIT("orphans:") <+> fsep (map ppr orphs),
636 ptext SLIT("family instance modules:") <+> fsep (map ppr finsts)
639 ppr_mod (mod_name, boot) = ppr mod_name <+> ppr_boot boot
640 ppr_boot True = text "[boot]"
641 ppr_boot False = empty
643 pprIfaceDecl :: (Version, IfaceDecl) -> SDoc
644 pprIfaceDecl (ver, decl)
645 = ppr_vers ver <+> ppr decl
647 -- Print the version for the decl
648 ppr_vers v | v == initialVersion = empty
651 pprFixities :: [(OccName, Fixity)] -> SDoc
652 pprFixities [] = empty
653 pprFixities fixes = ptext SLIT("fixities") <+> pprWithCommas pprFix fixes
655 pprFix (occ,fix) = ppr fix <+> ppr occ
657 pprVectInfo :: IfaceVectInfo -> SDoc
658 pprVectInfo (IfaceVectInfo names) =
659 ptext SLIT("Closured converted:") <+> hsep (map ppr names)
661 pprDeprecs NoDeprecs = empty
662 pprDeprecs (DeprecAll txt) = ptext SLIT("Deprecate all") <+> doubleQuotes (ftext txt)
663 pprDeprecs (DeprecSome prs) = ptext SLIT("Deprecate") <+> vcat (map pprDeprec prs)
665 pprDeprec (name, txt) = ppr name <+> doubleQuotes (ftext txt)
669 %*********************************************************
673 %*********************************************************
676 badIfaceFile file err
677 = vcat [ptext SLIT("Bad interface file:") <+> text file,
680 hiModuleNameMismatchWarn :: Module -> Module -> Message
681 hiModuleNameMismatchWarn requested_mod read_mod =
682 withPprStyle defaultUserStyle $
683 -- we want the Modules below to be qualified with package names,
684 -- so reset the PrintUnqualified setting.
685 hsep [ ptext SLIT("Something is amiss; requested module ")
687 , ptext SLIT("differs from name found in the interface file")
691 wrongIfaceModErr iface mod_name file_path
692 = sep [ptext SLIT("Interface file") <+> iface_file,
693 ptext SLIT("contains module") <+> quotes (ppr (mi_module iface)) <> comma,
694 ptext SLIT("but we were expecting module") <+> quotes (ppr mod_name),
695 sep [ptext SLIT("Probable cause: the source code which generated"),
697 ptext SLIT("has an incompatible module name")
700 where iface_file = doubleQuotes (text file_path)
702 homeModError mod location
703 = ptext SLIT("attempting to use module ") <> quotes (ppr mod)
704 <> (case ml_hs_file location of
705 Just file -> space <> parens (text file)
707 <+> ptext SLIT("which is not loaded")