1 -- -----------------------------------------------------------------------------
3 -- (c) The University of Glasgow, 2005
7 -- -----------------------------------------------------------------------------
13 defaultCleanupHandler,
16 -- * Flags and settings
17 DynFlags(..), DynFlag(..), Severity(..), HscTarget(..), dopt,
18 GhcMode(..), GhcLink(..), defaultObjectTarget,
25 Target(..), TargetId(..), Phase,
32 -- * Extending the program scope
33 extendGlobalRdrScope, -- :: Session -> [GlobalRdrElt] -> IO ()
34 setGlobalRdrScope, -- :: Session -> [GlobalRdrElt] -> IO ()
35 extendGlobalTypeScope, -- :: Session -> [Id] -> IO ()
36 setGlobalTypeScope, -- :: Session -> [Id] -> IO ()
38 -- * Loading\/compiling the program
40 load, LoadHowMuch(..), SuccessFlag(..), -- also does depanal
41 workingDirectoryChanged,
42 checkModule, CheckedModule(..),
43 TypecheckedSource, ParsedSource, RenamedSource,
46 -- * Parsing Haddock comments
49 -- * Inspecting the module structure of the program
50 ModuleGraph, ModSummary(..), ms_mod_name, ModLocation(..),
55 -- * Inspecting modules
60 modInfoPrintUnqualified,
63 modInfoIsExportedName,
68 PrintUnqualified, alwaysQualify,
70 -- * Interactive evaluation
71 getBindings, getPrintUnqual,
74 setContext, getContext,
83 runStmt, SingleStep(..),
85 Resume(resumeStmt, resumeThreadId, resumeBreakInfo, resumeSpan,
86 resumeHistory, resumeHistoryIx),
87 History(historyBreakInfo, historyEnclosingDecl),
88 GHC.getHistorySpan, getHistoryModule,
92 InteractiveEval.forward,
95 compileExpr, HValue, dynCompileExpr,
97 obtainTerm, obtainTerm1,
99 ModBreaks(..), BreakIndex,
100 BreakInfo(breakInfo_number, breakInfo_module),
101 BreakArray, setBreakOn, setBreakOff, getBreak,
104 -- * Abstract syntax elements
110 Module, mkModule, pprModule, moduleName, modulePackageId,
111 ModuleName, mkModuleName, moduleNameString,
115 isExternalName, nameModule, pprParenSymName, nameSrcSpan,
117 RdrName(Qual,Unqual),
121 isImplicitId, isDeadBinder,
122 isExportedId, isLocalId, isGlobalId,
124 isPrimOpId, isFCallId, isClassOpId_maybe,
125 isDataConWorkId, idDataCon,
126 isBottomingId, isDictonaryId,
127 recordSelectorFieldLabel,
129 -- ** Type constructors
131 tyConTyVars, tyConDataCons, tyConArity,
132 isClassTyCon, isSynTyCon, isNewTyCon, isPrimTyCon, isFunTyCon,
134 synTyConDefn, synTyConType, synTyConResKind,
140 -- ** Data constructors
142 dataConSig, dataConType, dataConTyCon, dataConFieldLabels,
143 dataConIsInfix, isVanillaDataCon,
145 StrictnessMark(..), isMarkedStrict,
149 classMethods, classSCTheta, classTvsFds,
154 instanceDFunId, pprInstance, pprInstanceHdr,
156 -- ** Types and Kinds
157 Type, dropForAlls, splitForAllTys, funResultTy,
158 pprParendType, pprTypeApp,
161 ThetaType, pprThetaArrow,
167 module HsSyn, -- ToDo: remove extraneous bits
171 defaultFixity, maxPrecedence,
175 -- ** Source locations
177 mkSrcLoc, isGoodSrcLoc, noSrcLoc,
178 srcLocFile, srcLocLine, srcLocCol,
180 mkSrcSpan, srcLocSpan, isGoodSrcSpan, noSrcSpan,
181 srcSpanStart, srcSpanEnd,
183 srcSpanStartLine, srcSpanEndLine,
184 srcSpanStartCol, srcSpanEndCol,
187 GhcException(..), showGhcException,
197 * inline bits of HscMain here to simplify layering: hscTcExpr, hscStmt.
198 * what StaticFlags should we expose, if any?
201 #include "HsVersions.h"
204 import qualified Linker
205 import Linker ( HValue )
210 import InteractiveEval
217 import Type hiding (typeKind)
218 import TcType hiding (typeKind)
220 import Var hiding (setIdType)
221 import TysPrim ( alphaTyVars )
226 import Name hiding ( varName )
227 import OccName ( parenSymOcc )
228 import InstEnv ( Instance, instanceDFunId, pprInstance, pprInstanceHdr )
232 import TcRnDriver ( tcRnModule )
233 import DriverPipeline
234 import DriverPhases ( HscSource(..), Phase(..), isHaskellSrcFilename, startPhase )
235 import HeaderInfo ( getImports, getOptions )
237 import HscMain ( newHscEnv, hscFileCheck, HscChecked(..) )
241 import SysTools ( initSysTools, cleanTempFiles, cleanTempFilesExcept,
251 import Bag ( unitBag, listToBag )
252 import ErrUtils ( Severity(..), showPass, fatalErrorMsg, debugTraceMsg,
253 mkPlainErrMsg, printBagOfErrors, printBagOfWarnings,
255 import qualified ErrUtils
257 import StringBuffer ( StringBuffer, hGetStringBuffer )
260 import Maybes ( expectJust, mapCatMaybes )
262 import HaddockLex ( tokenise )
264 import Control.Concurrent
265 import System.Directory ( getModificationTime, doesFileExist )
268 import qualified Data.List as List
270 import System.Exit ( exitWith, ExitCode(..) )
271 import System.Time ( ClockTime )
272 import Control.Exception as Exception hiding (handle)
275 import System.IO.Error ( try, isDoesNotExistError )
276 import Prelude hiding (init)
279 -- -----------------------------------------------------------------------------
280 -- Exception handlers
282 -- | Install some default exception handlers and run the inner computation.
283 -- Unless you want to handle exceptions yourself, you should wrap this around
284 -- the top level of your program. The default handlers output the error
285 -- message(s) to stderr and exit cleanly.
286 defaultErrorHandler :: DynFlags -> IO a -> IO a
287 defaultErrorHandler dflags inner =
288 -- top-level exception handler: any unrecognised exception is a compiler bug.
289 handle (\exception -> do
292 -- an IO exception probably isn't our fault, so don't panic
294 fatalErrorMsg dflags (text (show exception))
295 AsyncException StackOverflow ->
296 fatalErrorMsg dflags (text "stack overflow: use +RTS -K<size> to increase it")
298 fatalErrorMsg dflags (text (show (Panic (show exception))))
299 exitWith (ExitFailure 1)
302 -- program errors: messages with locations attached. Sometimes it is
303 -- convenient to just throw these as exceptions.
304 handleDyn (\dyn -> do printBagOfErrors dflags (unitBag dyn)
305 exitWith (ExitFailure 1)) $
307 -- error messages propagated as exceptions
308 handleDyn (\dyn -> do
311 PhaseFailed _ code -> exitWith code
312 Interrupted -> exitWith (ExitFailure 1)
313 _ -> do fatalErrorMsg dflags (text (show (dyn :: GhcException)))
314 exitWith (ExitFailure 1)
318 -- | Install a default cleanup handler to remove temporary files
319 -- deposited by a GHC run. This is seperate from
320 -- 'defaultErrorHandler', because you might want to override the error
321 -- handling, but still get the ordinary cleanup behaviour.
322 defaultCleanupHandler :: DynFlags -> IO a -> IO a
323 defaultCleanupHandler dflags inner =
324 -- make sure we clean up after ourselves
325 later (do cleanTempFiles dflags
328 -- exceptions will be blocked while we clean the temporary files,
329 -- so there shouldn't be any difficulty if we receive further
334 -- | Starts a new session. A session consists of a set of loaded
335 -- modules, a set of options (DynFlags), and an interactive context.
336 newSession :: Maybe FilePath -> IO Session
337 newSession mb_top_dir = do
339 main_thread <- myThreadId
340 modifyMVar_ interruptTargetThread (return . (main_thread :))
341 installSignalHandlers
344 dflags0 <- initSysTools mb_top_dir defaultDynFlags
345 dflags <- initDynFlags dflags0
346 env <- newHscEnv dflags
350 -- tmp: this breaks the abstraction, but required because DriverMkDepend
351 -- needs to call the Finder. ToDo: untangle this.
352 sessionHscEnv :: Session -> IO HscEnv
353 sessionHscEnv (Session ref) = readIORef ref
355 -- -----------------------------------------------------------------------------
358 -- | Grabs the DynFlags from the Session
359 getSessionDynFlags :: Session -> IO DynFlags
360 getSessionDynFlags s = withSession s (return . hsc_dflags)
362 -- | Updates the DynFlags in a Session. This also reads
363 -- the package database (unless it has already been read),
364 -- and prepares the compilers knowledge about packages. It
365 -- can be called again to load new packages: just add new
366 -- package flags to (packageFlags dflags).
368 -- Returns a list of new packages that may need to be linked in using
369 -- the dynamic linker (see 'linkPackages') as a result of new package
370 -- flags. If you are not doing linking or doing static linking, you
371 -- can ignore the list of packages returned.
373 setSessionDynFlags :: Session -> DynFlags -> IO [PackageId]
374 setSessionDynFlags (Session ref) dflags = do
375 hsc_env <- readIORef ref
376 (dflags', preload) <- initPackages dflags
377 writeIORef ref $! hsc_env{ hsc_dflags = dflags' }
380 -- | If there is no -o option, guess the name of target executable
381 -- by using top-level source file name as a base.
382 guessOutputFile :: Session -> IO ()
383 guessOutputFile s = modifySession s $ \env ->
384 let dflags = hsc_dflags env
385 mod_graph = hsc_mod_graph env
386 mainModuleSrcPath, guessedName :: Maybe String
387 mainModuleSrcPath = do
388 let isMain = (== mainModIs dflags) . ms_mod
389 [ms] <- return (filter isMain mod_graph)
390 ml_hs_file (ms_location ms)
391 guessedName = fmap basenameOf mainModuleSrcPath
393 case outputFile dflags of
395 Nothing -> env { hsc_dflags = dflags { outputFile = guessedName } }
397 -- -----------------------------------------------------------------------------
400 -- ToDo: think about relative vs. absolute file paths. And what
401 -- happens when the current directory changes.
403 -- | Sets the targets for this session. Each target may be a module name
404 -- or a filename. The targets correspond to the set of root modules for
405 -- the program\/library. Unloading the current program is achieved by
406 -- setting the current set of targets to be empty, followed by load.
407 setTargets :: Session -> [Target] -> IO ()
408 setTargets s targets = modifySession s (\h -> h{ hsc_targets = targets })
410 -- | returns the current set of targets
411 getTargets :: Session -> IO [Target]
412 getTargets s = withSession s (return . hsc_targets)
414 -- | Add another target
415 addTarget :: Session -> Target -> IO ()
417 = modifySession s (\h -> h{ hsc_targets = target : hsc_targets h })
420 removeTarget :: Session -> TargetId -> IO ()
421 removeTarget s target_id
422 = modifySession s (\h -> h{ hsc_targets = filter (hsc_targets h) })
424 filter targets = [ t | t@(Target id _) <- targets, id /= target_id ]
426 -- Attempts to guess what Target a string refers to. This function implements
427 -- the --make/GHCi command-line syntax for filenames:
429 -- - if the string looks like a Haskell source filename, then interpret
431 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
433 -- - otherwise interpret the string as a module name
435 guessTarget :: String -> Maybe Phase -> IO Target
436 guessTarget file (Just phase)
437 = return (Target (TargetFile file (Just phase)) Nothing)
438 guessTarget file Nothing
439 | isHaskellSrcFilename file
440 = return (Target (TargetFile file Nothing) Nothing)
442 = do exists <- doesFileExist hs_file
444 then return (Target (TargetFile hs_file Nothing) Nothing)
446 exists <- doesFileExist lhs_file
448 then return (Target (TargetFile lhs_file Nothing) Nothing)
450 return (Target (TargetModule (mkModuleName file)) Nothing)
452 hs_file = file `joinFileExt` "hs"
453 lhs_file = file `joinFileExt` "lhs"
455 -- -----------------------------------------------------------------------------
456 -- Extending the program scope
458 extendGlobalRdrScope :: Session -> [GlobalRdrElt] -> IO ()
459 extendGlobalRdrScope session rdrElts
460 = modifySession session $ \hscEnv ->
461 let global_rdr = hsc_global_rdr_env hscEnv
462 in hscEnv{ hsc_global_rdr_env = foldl extendGlobalRdrEnv global_rdr rdrElts }
464 setGlobalRdrScope :: Session -> [GlobalRdrElt] -> IO ()
465 setGlobalRdrScope session rdrElts
466 = modifySession session $ \hscEnv ->
467 hscEnv{ hsc_global_rdr_env = foldl extendGlobalRdrEnv emptyGlobalRdrEnv rdrElts }
469 extendGlobalTypeScope :: Session -> [Id] -> IO ()
470 extendGlobalTypeScope session ids
471 = modifySession session $ \hscEnv ->
472 let global_type = hsc_global_type_env hscEnv
473 in hscEnv{ hsc_global_type_env = extendTypeEnvWithIds global_type ids }
475 setGlobalTypeScope :: Session -> [Id] -> IO ()
476 setGlobalTypeScope session ids
477 = modifySession session $ \hscEnv ->
478 hscEnv{ hsc_global_type_env = extendTypeEnvWithIds emptyTypeEnv ids }
480 -- -----------------------------------------------------------------------------
481 -- Parsing Haddock comments
483 parseHaddockComment :: String -> Either String (HsDoc RdrName)
484 parseHaddockComment string = parseHaddockParagraphs (tokenise string)
486 -- -----------------------------------------------------------------------------
487 -- Loading the program
489 -- Perform a dependency analysis starting from the current targets
490 -- and update the session with the new module graph.
491 depanal :: Session -> [ModuleName] -> Bool -> IO (Maybe ModuleGraph)
492 depanal (Session ref) excluded_mods allow_dup_roots = do
493 hsc_env <- readIORef ref
495 dflags = hsc_dflags hsc_env
496 targets = hsc_targets hsc_env
497 old_graph = hsc_mod_graph hsc_env
499 showPass dflags "Chasing dependencies"
500 debugTraceMsg dflags 2 (hcat [
501 text "Chasing modules from: ",
502 hcat (punctuate comma (map pprTarget targets))])
504 r <- downsweep hsc_env old_graph excluded_mods allow_dup_roots
506 Just mod_graph -> writeIORef ref hsc_env{ hsc_mod_graph = mod_graph }
511 -- | The result of load.
513 = LoadOk Errors -- ^ all specified targets were loaded successfully.
514 | LoadFailed Errors -- ^ not all modules were loaded.
516 type Errors = [String]
518 data ErrMsg = ErrMsg {
519 errMsgSeverity :: Severity, -- warning, error, etc.
520 errMsgSpans :: [SrcSpan],
521 errMsgShortDoc :: Doc,
522 errMsgExtraInfo :: Doc
528 | LoadUpTo ModuleName
529 | LoadDependenciesOf ModuleName
531 -- | Try to load the program. If a Module is supplied, then just
532 -- attempt to load up to this target. If no Module is supplied,
533 -- then try to load all targets.
534 load :: Session -> LoadHowMuch -> IO SuccessFlag
535 load s@(Session ref) how_much
537 -- Dependency analysis first. Note that this fixes the module graph:
538 -- even if we don't get a fully successful upsweep, the full module
539 -- graph is still retained in the Session. We can tell which modules
540 -- were successfully loaded by inspecting the Session's HPT.
541 mb_graph <- depanal s [] False
543 Just mod_graph -> load2 s how_much mod_graph
544 Nothing -> return Failed
546 load2 s@(Session ref) how_much mod_graph = do
548 hsc_env <- readIORef ref
550 let hpt1 = hsc_HPT hsc_env
551 let dflags = hsc_dflags hsc_env
553 -- The "bad" boot modules are the ones for which we have
554 -- B.hs-boot in the module graph, but no B.hs
555 -- The downsweep should have ensured this does not happen
557 let all_home_mods = [ms_mod_name s
558 | s <- mod_graph, not (isBootSummary s)]
560 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
561 not (ms_mod_name s `elem` all_home_mods)]
563 ASSERT( null bad_boot_mods ) return ()
565 -- mg2_with_srcimps drops the hi-boot nodes, returning a
566 -- graph with cycles. Among other things, it is used for
567 -- backing out partially complete cycles following a failed
568 -- upsweep, and for removing from hpt all the modules
569 -- not in strict downwards closure, during calls to compile.
570 let mg2_with_srcimps :: [SCC ModSummary]
571 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
573 -- If we can determine that any of the {-# SOURCE #-} imports
574 -- are definitely unnecessary, then emit a warning.
575 warnUnnecessarySourceImports dflags mg2_with_srcimps
578 -- check the stability property for each module.
579 stable_mods@(stable_obj,stable_bco)
580 = checkStability hpt1 mg2_with_srcimps all_home_mods
582 -- prune bits of the HPT which are definitely redundant now,
584 pruned_hpt = pruneHomePackageTable hpt1
585 (flattenSCCs mg2_with_srcimps)
590 debugTraceMsg dflags 2 (text "Stable obj:" <+> ppr stable_obj $$
591 text "Stable BCO:" <+> ppr stable_bco)
593 -- Unload any modules which are going to be re-linked this time around.
594 let stable_linkables = [ linkable
595 | m <- stable_obj++stable_bco,
596 Just hmi <- [lookupUFM pruned_hpt m],
597 Just linkable <- [hm_linkable hmi] ]
598 unload hsc_env stable_linkables
600 -- We could at this point detect cycles which aren't broken by
601 -- a source-import, and complain immediately, but it seems better
602 -- to let upsweep_mods do this, so at least some useful work gets
603 -- done before the upsweep is abandoned.
604 --hPutStrLn stderr "after tsort:\n"
605 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
607 -- Now do the upsweep, calling compile for each module in
608 -- turn. Final result is version 3 of everything.
610 -- Topologically sort the module graph, this time including hi-boot
611 -- nodes, and possibly just including the portion of the graph
612 -- reachable from the module specified in the 2nd argument to load.
613 -- This graph should be cycle-free.
614 -- If we're restricting the upsweep to a portion of the graph, we
615 -- also want to retain everything that is still stable.
616 let full_mg :: [SCC ModSummary]
617 full_mg = topSortModuleGraph False mod_graph Nothing
619 maybe_top_mod = case how_much of
621 LoadDependenciesOf m -> Just m
624 partial_mg0 :: [SCC ModSummary]
625 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
627 -- LoadDependenciesOf m: we want the upsweep to stop just
628 -- short of the specified module (unless the specified module
631 | LoadDependenciesOf mod <- how_much
632 = ASSERT( case last partial_mg0 of
633 AcyclicSCC ms -> ms_mod_name ms == mod; _ -> False )
634 List.init partial_mg0
640 | AcyclicSCC ms <- full_mg,
641 ms_mod_name ms `elem` stable_obj++stable_bco,
642 ms_mod_name ms `notElem` [ ms_mod_name ms' |
643 AcyclicSCC ms' <- partial_mg ] ]
645 mg = stable_mg ++ partial_mg
647 -- clean up between compilations
648 let cleanup = cleanTempFilesExcept dflags
649 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
651 debugTraceMsg dflags 2 (hang (text "Ready for upsweep")
653 (upsweep_ok, hsc_env1, modsUpswept)
654 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
655 pruned_hpt stable_mods cleanup mg
657 -- Make modsDone be the summaries for each home module now
658 -- available; this should equal the domain of hpt3.
659 -- Get in in a roughly top .. bottom order (hence reverse).
661 let modsDone = reverse modsUpswept
663 -- Try and do linking in some form, depending on whether the
664 -- upsweep was completely or only partially successful.
666 if succeeded upsweep_ok
669 -- Easy; just relink it all.
670 do debugTraceMsg dflags 2 (text "Upsweep completely successful.")
672 -- Clean up after ourselves
673 cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
675 -- Issue a warning for the confusing case where the user
676 -- said '-o foo' but we're not going to do any linking.
677 -- We attempt linking if either (a) one of the modules is
678 -- called Main, or (b) the user said -no-hs-main, indicating
679 -- that main() is going to come from somewhere else.
681 let ofile = outputFile dflags
682 let no_hs_main = dopt Opt_NoHsMain dflags
684 main_mod = mainModIs dflags
685 a_root_is_Main = any ((==main_mod).ms_mod) mod_graph
686 do_linking = a_root_is_Main || no_hs_main
688 when (ghcLink dflags == LinkBinary
689 && isJust ofile && not do_linking) $
690 debugTraceMsg dflags 1 $
691 text ("Warning: output was redirected with -o, " ++
692 "but no output will be generated\n" ++
693 "because there is no " ++
694 moduleNameString (moduleName main_mod) ++ " module.")
696 -- link everything together
697 linkresult <- link (ghcLink dflags) dflags do_linking (hsc_HPT hsc_env1)
699 loadFinish Succeeded linkresult ref hsc_env1
702 -- Tricky. We need to back out the effects of compiling any
703 -- half-done cycles, both so as to clean up the top level envs
704 -- and to avoid telling the interactive linker to link them.
705 do debugTraceMsg dflags 2 (text "Upsweep partially successful.")
708 = map ms_mod modsDone
709 let mods_to_zap_names
710 = findPartiallyCompletedCycles modsDone_names
713 = filter ((`notElem` mods_to_zap_names).ms_mod)
716 let hpt4 = retainInTopLevelEnvs (map ms_mod_name mods_to_keep)
719 -- Clean up after ourselves
720 cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
722 -- there should be no Nothings where linkables should be, now
723 ASSERT(all (isJust.hm_linkable)
724 (eltsUFM (hsc_HPT hsc_env))) do
726 -- Link everything together
727 linkresult <- link (ghcLink dflags) dflags False hpt4
729 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
730 loadFinish Failed linkresult ref hsc_env4
732 -- Finish up after a load.
734 -- If the link failed, unload everything and return.
735 loadFinish all_ok Failed ref hsc_env
736 = do unload hsc_env []
737 writeIORef ref $! discardProg hsc_env
740 -- Empty the interactive context and set the module context to the topmost
741 -- newly loaded module, or the Prelude if none were loaded.
742 loadFinish all_ok Succeeded ref hsc_env
743 = do writeIORef ref $! hsc_env{ hsc_IC = emptyInteractiveContext }
747 -- Forget the current program, but retain the persistent info in HscEnv
748 discardProg :: HscEnv -> HscEnv
750 = hsc_env { hsc_mod_graph = emptyMG,
751 hsc_IC = emptyInteractiveContext,
752 hsc_HPT = emptyHomePackageTable }
754 -- used to fish out the preprocess output files for the purposes of
755 -- cleaning up. The preprocessed file *might* be the same as the
756 -- source file, but that doesn't do any harm.
757 ppFilesFromSummaries summaries = map ms_hspp_file summaries
759 -- -----------------------------------------------------------------------------
763 CheckedModule { parsedSource :: ParsedSource,
764 renamedSource :: Maybe RenamedSource,
765 typecheckedSource :: Maybe TypecheckedSource,
766 checkedModuleInfo :: Maybe ModuleInfo,
767 coreBinds :: Maybe [CoreBind]
769 -- ToDo: improvements that could be made here:
770 -- if the module succeeded renaming but not typechecking,
771 -- we can still get back the GlobalRdrEnv and exports, so
772 -- perhaps the ModuleInfo should be split up into separate
773 -- fields within CheckedModule.
775 type ParsedSource = Located (HsModule RdrName)
776 type RenamedSource = (HsGroup Name, [LImportDecl Name], Maybe [LIE Name],
777 Maybe (HsDoc Name), HaddockModInfo Name)
778 type TypecheckedSource = LHsBinds Id
781 -- - things that aren't in the output of the typechecker right now:
785 -- - type/data/newtype declarations
786 -- - class declarations
788 -- - extra things in the typechecker's output:
789 -- - default methods are turned into top-level decls.
790 -- - dictionary bindings
793 -- | This is the way to get access to parsed and typechecked source code
794 -- for a module. 'checkModule' attempts to typecheck the module. If
795 -- successful, it returns the abstract syntax for the module.
796 -- If compileToCore is true, it also desugars the module and returns the
797 -- resulting Core bindings as a component of the CheckedModule.
798 checkModule :: Session -> ModuleName -> Bool -> IO (Maybe CheckedModule)
799 checkModule session@(Session ref) mod compileToCore = do
800 -- parse & typecheck the module
801 hsc_env <- readIORef ref
802 let mg = hsc_mod_graph hsc_env
803 case [ ms | ms <- mg, ms_mod_name ms == mod ] of
806 mbChecked <- hscFileCheck
807 hsc_env{hsc_dflags=ms_hspp_opts ms}
810 Nothing -> return Nothing
811 Just (HscChecked parsed renamed Nothing _) ->
812 return (Just (CheckedModule {
813 parsedSource = parsed,
814 renamedSource = renamed,
815 typecheckedSource = Nothing,
816 checkedModuleInfo = Nothing,
817 coreBinds = Nothing }))
818 Just (HscChecked parsed renamed
819 (Just (tc_binds, rdr_env, details))
820 maybeCoreBinds) -> do
821 let minf = ModuleInfo {
822 minf_type_env = md_types details,
823 minf_exports = availsToNameSet $
825 minf_rdr_env = Just rdr_env,
826 minf_instances = md_insts details
828 ,minf_modBreaks = emptyModBreaks
831 return (Just (CheckedModule {
832 parsedSource = parsed,
833 renamedSource = renamed,
834 typecheckedSource = Just tc_binds,
835 checkedModuleInfo = Just minf,
836 coreBinds = maybeCoreBinds}))
838 -- | This is the way to get access to the Core bindings corresponding
839 -- to a module. 'compileToCore' invokes 'checkModule' to parse, typecheck, and
840 -- desugar the module, then returns the resulting list of Core bindings if
842 compileToCore :: Session -> FilePath -> IO (Maybe [CoreBind])
843 compileToCore session@(Session ref) fn = do
844 hsc_env <- readIORef ref
845 -- First, set the target to the desired filename
846 target <- guessTarget fn Nothing
847 addTarget session target
848 load session LoadAllTargets
849 -- Then find dependencies
850 maybeModGraph <- depanal session [] True
851 case maybeModGraph of
852 Nothing -> return Nothing
854 case find ((== fn) . msHsFilePath) modGraph of
855 Just modSummary -> do
856 -- Now we have the module name;
857 -- parse, typecheck and desugar the module
858 let mod = ms_mod_name modSummary
859 maybeCheckedModule <- checkModule session mod True
860 case maybeCheckedModule of
861 Nothing -> return Nothing
862 Just checkedMod -> return $ coreBinds checkedMod
863 -- ---------------------------------------------------------------------------
866 unload :: HscEnv -> [Linkable] -> IO ()
867 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
868 = case ghcLink (hsc_dflags hsc_env) of
870 LinkInMemory -> Linker.unload (hsc_dflags hsc_env) stable_linkables
872 LinkInMemory -> panic "unload: no interpreter"
876 -- -----------------------------------------------------------------------------
880 Stability tells us which modules definitely do not need to be recompiled.
881 There are two main reasons for having stability:
883 - avoid doing a complete upsweep of the module graph in GHCi when
884 modules near the bottom of the tree have not changed.
886 - to tell GHCi when it can load object code: we can only load object code
887 for a module when we also load object code fo all of the imports of the
888 module. So we need to know that we will definitely not be recompiling
889 any of these modules, and we can use the object code.
891 The stability check is as follows. Both stableObject and
892 stableBCO are used during the upsweep phase later.
895 stable m = stableObject m || stableBCO m
898 all stableObject (imports m)
899 && old linkable does not exist, or is == on-disk .o
900 && date(on-disk .o) > date(.hs)
903 all stable (imports m)
904 && date(BCO) > date(.hs)
907 These properties embody the following ideas:
909 - if a module is stable, then:
910 - if it has been compiled in a previous pass (present in HPT)
911 then it does not need to be compiled or re-linked.
912 - if it has not been compiled in a previous pass,
913 then we only need to read its .hi file from disk and
914 link it to produce a ModDetails.
916 - if a modules is not stable, we will definitely be at least
917 re-linking, and possibly re-compiling it during the upsweep.
918 All non-stable modules can (and should) therefore be unlinked
921 - Note that objects are only considered stable if they only depend
922 on other objects. We can't link object code against byte code.
926 :: HomePackageTable -- HPT from last compilation
927 -> [SCC ModSummary] -- current module graph (cyclic)
928 -> [ModuleName] -- all home modules
929 -> ([ModuleName], -- stableObject
930 [ModuleName]) -- stableBCO
932 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
934 checkSCC (stable_obj, stable_bco) scc0
935 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
936 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
937 | otherwise = (stable_obj, stable_bco)
939 scc = flattenSCC scc0
940 scc_mods = map ms_mod_name scc
941 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
943 scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
944 -- all imports outside the current SCC, but in the home pkg
946 stable_obj_imps = map (`elem` stable_obj) scc_allimps
947 stable_bco_imps = map (`elem` stable_bco) scc_allimps
954 and (zipWith (||) stable_obj_imps stable_bco_imps)
958 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
962 same_as_prev t = case lookupUFM hpt (ms_mod_name ms) of
963 Just hmi | Just l <- hm_linkable hmi
964 -> isObjectLinkable l && t == linkableTime l
966 -- why '>=' rather than '>' above? If the filesystem stores
967 -- times to the nearset second, we may occasionally find that
968 -- the object & source have the same modification time,
969 -- especially if the source was automatically generated
970 -- and compiled. Using >= is slightly unsafe, but it matches
974 = case lookupUFM hpt (ms_mod_name ms) of
975 Just hmi | Just l <- hm_linkable hmi ->
976 not (isObjectLinkable l) &&
977 linkableTime l >= ms_hs_date ms
980 ms_allimps :: ModSummary -> [ModuleName]
981 ms_allimps ms = map unLoc (ms_srcimps ms ++ ms_imps ms)
983 -- -----------------------------------------------------------------------------
984 -- Prune the HomePackageTable
986 -- Before doing an upsweep, we can throw away:
988 -- - For non-stable modules:
989 -- - all ModDetails, all linked code
990 -- - all unlinked code that is out of date with respect to
993 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
994 -- space at the end of the upsweep, because the topmost ModDetails of the
995 -- old HPT holds on to the entire type environment from the previous
998 pruneHomePackageTable
1001 -> ([ModuleName],[ModuleName])
1004 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
1007 | is_stable modl = hmi'
1008 | otherwise = hmi'{ hm_details = emptyModDetails }
1010 modl = moduleName (mi_module (hm_iface hmi))
1011 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
1012 = hmi{ hm_linkable = Nothing }
1015 where ms = expectJust "prune" (lookupUFM ms_map modl)
1017 ms_map = listToUFM [(ms_mod_name ms, ms) | ms <- summ]
1019 is_stable m = m `elem` stable_obj || m `elem` stable_bco
1021 -- -----------------------------------------------------------------------------
1023 -- Return (names of) all those in modsDone who are part of a cycle
1024 -- as defined by theGraph.
1025 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
1026 findPartiallyCompletedCycles modsDone theGraph
1030 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
1031 chew ((CyclicSCC vs):rest)
1032 = let names_in_this_cycle = nub (map ms_mod vs)
1034 = nub ([done | done <- modsDone,
1035 done `elem` names_in_this_cycle])
1036 chewed_rest = chew rest
1038 if notNull mods_in_this_cycle
1039 && length mods_in_this_cycle < length names_in_this_cycle
1040 then mods_in_this_cycle ++ chewed_rest
1043 -- -----------------------------------------------------------------------------
1046 -- This is where we compile each module in the module graph, in a pass
1047 -- from the bottom to the top of the graph.
1049 -- There better had not be any cyclic groups here -- we check for them.
1052 :: HscEnv -- Includes initially-empty HPT
1053 -> HomePackageTable -- HPT from last time round (pruned)
1054 -> ([ModuleName],[ModuleName]) -- stable modules (see checkStability)
1055 -> IO () -- How to clean up unwanted tmp files
1056 -> [SCC ModSummary] -- Mods to do (the worklist)
1058 HscEnv, -- With an updated HPT
1059 [ModSummary]) -- Mods which succeeded
1061 upsweep hsc_env old_hpt stable_mods cleanup mods
1062 = upsweep' hsc_env old_hpt stable_mods cleanup mods 1 (length mods)
1064 upsweep' hsc_env old_hpt stable_mods cleanup
1066 = return (Succeeded, hsc_env, [])
1068 upsweep' hsc_env old_hpt stable_mods cleanup
1069 (CyclicSCC ms:_) _ _
1070 = do fatalErrorMsg (hsc_dflags hsc_env) (cyclicModuleErr ms)
1071 return (Failed, hsc_env, [])
1073 upsweep' hsc_env old_hpt stable_mods cleanup
1074 (AcyclicSCC mod:mods) mod_index nmods
1075 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
1076 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
1077 -- (moduleEnvElts (hsc_HPT hsc_env)))
1079 mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods mod
1082 cleanup -- Remove unwanted tmp files between compilations
1085 Nothing -> return (Failed, hsc_env, [])
1087 { let this_mod = ms_mod_name mod
1089 -- Add new info to hsc_env
1090 hpt1 = addToUFM (hsc_HPT hsc_env) this_mod mod_info
1091 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
1093 -- Space-saving: delete the old HPT entry
1094 -- for mod BUT if mod is a hs-boot
1095 -- node, don't delete it. For the
1096 -- interface, the HPT entry is probaby for the
1097 -- main Haskell source file. Deleting it
1098 -- would force .. (what?? --SDM)
1099 old_hpt1 | isBootSummary mod = old_hpt
1100 | otherwise = delFromUFM old_hpt this_mod
1102 ; (restOK, hsc_env2, modOKs)
1103 <- upsweep' hsc_env1 old_hpt1 stable_mods cleanup
1104 mods (mod_index+1) nmods
1105 ; return (restOK, hsc_env2, mod:modOKs)
1109 -- Compile a single module. Always produce a Linkable for it if
1110 -- successful. If no compilation happened, return the old Linkable.
1111 upsweep_mod :: HscEnv
1113 -> ([ModuleName],[ModuleName])
1115 -> Int -- index of module
1116 -> Int -- total number of modules
1117 -> IO (Maybe HomeModInfo) -- Nothing => Failed
1119 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) summary mod_index nmods
1121 this_mod_name = ms_mod_name summary
1122 this_mod = ms_mod summary
1123 mb_obj_date = ms_obj_date summary
1124 obj_fn = ml_obj_file (ms_location summary)
1125 hs_date = ms_hs_date summary
1127 is_stable_obj = this_mod_name `elem` stable_obj
1128 is_stable_bco = this_mod_name `elem` stable_bco
1130 old_hmi = lookupUFM old_hpt this_mod_name
1132 -- We're using the dflags for this module now, obtained by
1133 -- applying any options in its LANGUAGE & OPTIONS_GHC pragmas.
1134 dflags = ms_hspp_opts summary
1135 prevailing_target = hscTarget (hsc_dflags hsc_env)
1136 local_target = hscTarget dflags
1138 -- If OPTIONS_GHC contains -fasm or -fvia-C, be careful that
1139 -- we don't do anything dodgy: these should only work to change
1140 -- from -fvia-C to -fasm and vice-versa, otherwise we could
1141 -- end up trying to link object code to byte code.
1142 target = if prevailing_target /= local_target
1143 && (not (isObjectTarget prevailing_target)
1144 || not (isObjectTarget local_target))
1145 then prevailing_target
1148 -- store the corrected hscTarget into the summary
1149 summary' = summary{ ms_hspp_opts = dflags { hscTarget = target } }
1151 -- The old interface is ok if
1152 -- a) we're compiling a source file, and the old HPT
1153 -- entry is for a source file
1154 -- b) we're compiling a hs-boot file
1155 -- Case (b) allows an hs-boot file to get the interface of its
1156 -- real source file on the second iteration of the compilation
1157 -- manager, but that does no harm. Otherwise the hs-boot file
1158 -- will always be recompiled
1163 Just hm_info | isBootSummary summary -> Just iface
1164 | not (mi_boot iface) -> Just iface
1165 | otherwise -> Nothing
1167 iface = hm_iface hm_info
1169 compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
1170 compile_it = upsweep_compile hsc_env old_hpt this_mod_name
1171 summary' mod_index nmods mb_old_iface
1173 compile_it_discard_iface
1174 = upsweep_compile hsc_env old_hpt this_mod_name
1175 summary' mod_index nmods Nothing
1181 -- Regardless of whether we're generating object code or
1182 -- byte code, we can always use an existing object file
1183 -- if it is *stable* (see checkStability).
1184 | is_stable_obj, isJust old_hmi ->
1186 -- object is stable, and we have an entry in the
1187 -- old HPT: nothing to do
1189 | is_stable_obj, isNothing old_hmi -> do
1190 linkable <- findObjectLinkable this_mod obj_fn
1191 (expectJust "upseep1" mb_obj_date)
1192 compile_it (Just linkable)
1193 -- object is stable, but we need to load the interface
1194 -- off disk to make a HMI.
1198 ASSERT(isJust old_hmi) -- must be in the old_hpt
1200 -- BCO is stable: nothing to do
1202 | Just hmi <- old_hmi,
1203 Just l <- hm_linkable hmi, not (isObjectLinkable l),
1204 linkableTime l >= ms_hs_date summary ->
1206 -- we have an old BCO that is up to date with respect
1207 -- to the source: do a recompilation check as normal.
1211 -- no existing code at all: we must recompile.
1213 -- When generating object code, if there's an up-to-date
1214 -- object file on the disk, then we can use it.
1215 -- However, if the object file is new (compared to any
1216 -- linkable we had from a previous compilation), then we
1217 -- must discard any in-memory interface, because this
1218 -- means the user has compiled the source file
1219 -- separately and generated a new interface, that we must
1220 -- read from the disk.
1222 obj | isObjectTarget obj,
1223 Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
1226 | Just l <- hm_linkable hmi,
1227 isObjectLinkable l && linkableTime l == obj_date
1228 -> compile_it (Just l)
1230 linkable <- findObjectLinkable this_mod obj_fn obj_date
1231 compile_it_discard_iface (Just linkable)
1237 -- Run hsc to compile a module
1238 upsweep_compile hsc_env old_hpt this_mod summary
1243 compresult <- compile hsc_env summary mb_old_linkable mb_old_iface
1247 -- Compilation failed. Compile may still have updated the PCS, tho.
1248 CompErrs -> return Nothing
1250 -- Compilation "succeeded", and may or may not have returned a new
1251 -- linkable (depending on whether compilation was actually performed
1253 CompOK new_details new_iface new_linkable
1254 -> do let new_info = HomeModInfo { hm_iface = new_iface,
1255 hm_details = new_details,
1256 hm_linkable = new_linkable }
1257 return (Just new_info)
1260 -- Filter modules in the HPT
1261 retainInTopLevelEnvs :: [ModuleName] -> HomePackageTable -> HomePackageTable
1262 retainInTopLevelEnvs keep_these hpt
1263 = listToUFM [ (mod, expectJust "retain" mb_mod_info)
1265 , let mb_mod_info = lookupUFM hpt mod
1266 , isJust mb_mod_info ]
1268 -- ---------------------------------------------------------------------------
1269 -- Topological sort of the module graph
1272 :: Bool -- Drop hi-boot nodes? (see below)
1276 -- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1277 -- The resulting list of strongly-connected-components is in topologically
1278 -- sorted order, starting with the module(s) at the bottom of the
1279 -- dependency graph (ie compile them first) and ending with the ones at
1282 -- Drop hi-boot nodes (first boolean arg)?
1284 -- False: treat the hi-boot summaries as nodes of the graph,
1285 -- so the graph must be acyclic
1287 -- True: eliminate the hi-boot nodes, and instead pretend
1288 -- the a source-import of Foo is an import of Foo
1289 -- The resulting graph has no hi-boot nodes, but can by cyclic
1291 topSortModuleGraph drop_hs_boot_nodes summaries Nothing
1292 = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
1293 topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
1294 = stronglyConnComp (map vertex_fn (reachable graph root))
1296 -- restrict the graph to just those modules reachable from
1297 -- the specified module. We do this by building a graph with
1298 -- the full set of nodes, and determining the reachable set from
1299 -- the specified node.
1300 (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
1301 (graph, vertex_fn, key_fn) = graphFromEdges' nodes
1303 | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
1304 | otherwise = throwDyn (ProgramError "module does not exist")
1306 moduleGraphNodes :: Bool -> [ModSummary]
1307 -> ([(ModSummary, Int, [Int])], HscSource -> ModuleName -> Maybe Int)
1308 moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
1310 -- Drop hs-boot nodes by using HsSrcFile as the key
1311 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1312 | otherwise = HsBootFile
1314 -- We use integers as the keys for the SCC algorithm
1315 nodes :: [(ModSummary, Int, [Int])]
1316 nodes = [(s, expectJust "topSort" $
1317 lookup_key (ms_hsc_src s) (ms_mod_name s),
1318 out_edge_keys hs_boot_key (map unLoc (ms_srcimps s)) ++
1319 out_edge_keys HsSrcFile (map unLoc (ms_imps s)) ++
1320 (-- see [boot-edges] below
1321 if drop_hs_boot_nodes || ms_hsc_src s == HsBootFile
1323 else case lookup_key HsBootFile (ms_mod_name s) of
1328 , not (isBootSummary s && drop_hs_boot_nodes) ]
1329 -- Drop the hi-boot ones if told to do so
1331 -- [boot-edges] if this is a .hs and there is an equivalent
1332 -- .hs-boot, add a link from the former to the latter. This
1333 -- has the effect of detecting bogus cases where the .hs-boot
1334 -- depends on the .hs, by introducing a cycle. Additionally,
1335 -- it ensures that we will always process the .hs-boot before
1336 -- the .hs, and so the HomePackageTable will always have the
1337 -- most up to date information.
1339 key_map :: NodeMap Int
1340 key_map = listToFM ([(moduleName (ms_mod s), ms_hsc_src s)
1344 lookup_key :: HscSource -> ModuleName -> Maybe Int
1345 lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
1347 out_edge_keys :: HscSource -> [ModuleName] -> [Int]
1348 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1349 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1350 -- the IsBootInterface parameter True; else False
1353 type NodeKey = (ModuleName, HscSource) -- The nodes of the graph are
1354 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1356 msKey :: ModSummary -> NodeKey
1357 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (moduleName mod,boot)
1359 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1360 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1362 nodeMapElts :: NodeMap a -> [a]
1363 nodeMapElts = eltsFM
1365 -- If there are {-# SOURCE #-} imports between strongly connected
1366 -- components in the topological sort, then those imports can
1367 -- definitely be replaced by ordinary non-SOURCE imports: if SOURCE
1368 -- were necessary, then the edge would be part of a cycle.
1369 warnUnnecessarySourceImports :: DynFlags -> [SCC ModSummary] -> IO ()
1370 warnUnnecessarySourceImports dflags sccs =
1371 printBagOfWarnings dflags (listToBag (concat (map (check.flattenSCC) sccs)))
1373 let mods_in_this_cycle = map ms_mod_name ms in
1374 [ warn m i | m <- ms, i <- ms_srcimps m,
1375 unLoc i `notElem` mods_in_this_cycle ]
1377 warn :: ModSummary -> Located ModuleName -> WarnMsg
1378 warn ms (L loc mod) =
1380 (ptext SLIT("Warning: {-# SOURCE #-} unnecessary in import of ")
1381 <+> quotes (ppr mod))
1383 -----------------------------------------------------------------------------
1384 -- Downsweep (dependency analysis)
1386 -- Chase downwards from the specified root set, returning summaries
1387 -- for all home modules encountered. Only follow source-import
1390 -- We pass in the previous collection of summaries, which is used as a
1391 -- cache to avoid recalculating a module summary if the source is
1394 -- The returned list of [ModSummary] nodes has one node for each home-package
1395 -- module, plus one for any hs-boot files. The imports of these nodes
1396 -- are all there, including the imports of non-home-package modules.
1399 -> [ModSummary] -- Old summaries
1400 -> [ModuleName] -- Ignore dependencies on these; treat
1401 -- them as if they were package modules
1402 -> Bool -- True <=> allow multiple targets to have
1403 -- the same module name; this is
1404 -- very useful for ghc -M
1405 -> IO (Maybe [ModSummary])
1406 -- The elts of [ModSummary] all have distinct
1407 -- (Modules, IsBoot) identifiers, unless the Bool is true
1408 -- in which case there can be repeats
1409 downsweep hsc_env old_summaries excl_mods allow_dup_roots
1410 = -- catch error messages and return them
1411 handleDyn (\err_msg -> printBagOfErrors (hsc_dflags hsc_env) (unitBag err_msg) >> return Nothing) $ do
1412 rootSummaries <- mapM getRootSummary roots
1413 let root_map = mkRootMap rootSummaries
1414 checkDuplicates root_map
1415 summs <- loop (concatMap msDeps rootSummaries) root_map
1418 roots = hsc_targets hsc_env
1420 old_summary_map :: NodeMap ModSummary
1421 old_summary_map = mkNodeMap old_summaries
1423 getRootSummary :: Target -> IO ModSummary
1424 getRootSummary (Target (TargetFile file mb_phase) maybe_buf)
1425 = do exists <- doesFileExist file
1427 then summariseFile hsc_env old_summaries file mb_phase maybe_buf
1428 else throwDyn $ mkPlainErrMsg noSrcSpan $
1429 text "can't find file:" <+> text file
1430 getRootSummary (Target (TargetModule modl) maybe_buf)
1431 = do maybe_summary <- summariseModule hsc_env old_summary_map False
1432 (L rootLoc modl) maybe_buf excl_mods
1433 case maybe_summary of
1434 Nothing -> packageModErr modl
1437 rootLoc = mkGeneralSrcSpan FSLIT("<command line>")
1439 -- In a root module, the filename is allowed to diverge from the module
1440 -- name, so we have to check that there aren't multiple root files
1441 -- defining the same module (otherwise the duplicates will be silently
1442 -- ignored, leading to confusing behaviour).
1443 checkDuplicates :: NodeMap [ModSummary] -> IO ()
1444 checkDuplicates root_map
1445 | allow_dup_roots = return ()
1446 | null dup_roots = return ()
1447 | otherwise = multiRootsErr (head dup_roots)
1449 dup_roots :: [[ModSummary]] -- Each at least of length 2
1450 dup_roots = filterOut isSingleton (nodeMapElts root_map)
1452 loop :: [(Located ModuleName,IsBootInterface)]
1453 -- Work list: process these modules
1454 -> NodeMap [ModSummary]
1455 -- Visited set; the range is a list because
1456 -- the roots can have the same module names
1457 -- if allow_dup_roots is True
1459 -- The result includes the worklist, except
1460 -- for those mentioned in the visited set
1461 loop [] done = return (concat (nodeMapElts done))
1462 loop ((wanted_mod, is_boot) : ss) done
1463 | Just summs <- lookupFM done key
1464 = if isSingleton summs then
1467 do { multiRootsErr summs; return [] }
1468 | otherwise = do { mb_s <- summariseModule hsc_env old_summary_map
1469 is_boot wanted_mod Nothing excl_mods
1471 Nothing -> loop ss done
1472 Just s -> loop (msDeps s ++ ss)
1473 (addToFM done key [s]) }
1475 key = (unLoc wanted_mod, if is_boot then HsBootFile else HsSrcFile)
1477 mkRootMap :: [ModSummary] -> NodeMap [ModSummary]
1478 mkRootMap summaries = addListToFM_C (++) emptyFM
1479 [ (msKey s, [s]) | s <- summaries ]
1481 msDeps :: ModSummary -> [(Located ModuleName, IsBootInterface)]
1482 -- (msDeps s) returns the dependencies of the ModSummary s.
1483 -- A wrinkle is that for a {-# SOURCE #-} import we return
1484 -- *both* the hs-boot file
1485 -- *and* the source file
1486 -- as "dependencies". That ensures that the list of all relevant
1487 -- modules always contains B.hs if it contains B.hs-boot.
1488 -- Remember, this pass isn't doing the topological sort. It's
1489 -- just gathering the list of all relevant ModSummaries
1491 concat [ [(m,True), (m,False)] | m <- ms_srcimps s ]
1492 ++ [ (m,False) | m <- ms_imps s ]
1494 -----------------------------------------------------------------------------
1495 -- Summarising modules
1497 -- We have two types of summarisation:
1499 -- * Summarise a file. This is used for the root module(s) passed to
1500 -- cmLoadModules. The file is read, and used to determine the root
1501 -- module name. The module name may differ from the filename.
1503 -- * Summarise a module. We are given a module name, and must provide
1504 -- a summary. The finder is used to locate the file in which the module
1509 -> [ModSummary] -- old summaries
1510 -> FilePath -- source file name
1511 -> Maybe Phase -- start phase
1512 -> Maybe (StringBuffer,ClockTime)
1515 summariseFile hsc_env old_summaries file mb_phase maybe_buf
1516 -- we can use a cached summary if one is available and the
1517 -- source file hasn't changed, But we have to look up the summary
1518 -- by source file, rather than module name as we do in summarise.
1519 | Just old_summary <- findSummaryBySourceFile old_summaries file
1521 let location = ms_location old_summary
1523 -- return the cached summary if the source didn't change
1524 src_timestamp <- case maybe_buf of
1525 Just (_,t) -> return t
1526 Nothing -> getModificationTime file
1527 -- The file exists; we checked in getRootSummary above.
1528 -- If it gets removed subsequently, then this
1529 -- getModificationTime may fail, but that's the right
1532 if ms_hs_date old_summary == src_timestamp
1533 then do -- update the object-file timestamp
1534 obj_timestamp <- getObjTimestamp location False
1535 return old_summary{ ms_obj_date = obj_timestamp }
1543 let dflags = hsc_dflags hsc_env
1545 (dflags', hspp_fn, buf)
1546 <- preprocessFile dflags file mb_phase maybe_buf
1548 (srcimps,the_imps, L _ mod_name) <- getImports dflags' buf hspp_fn
1550 -- Make a ModLocation for this file
1551 location <- mkHomeModLocation dflags mod_name file
1553 -- Tell the Finder cache where it is, so that subsequent calls
1554 -- to findModule will find it, even if it's not on any search path
1555 mod <- addHomeModuleToFinder hsc_env mod_name location
1557 src_timestamp <- case maybe_buf of
1558 Just (_,t) -> return t
1559 Nothing -> getModificationTime file
1560 -- getMofificationTime may fail
1562 obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
1564 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
1565 ms_location = location,
1566 ms_hspp_file = hspp_fn,
1567 ms_hspp_opts = dflags',
1568 ms_hspp_buf = Just buf,
1569 ms_srcimps = srcimps, ms_imps = the_imps,
1570 ms_hs_date = src_timestamp,
1571 ms_obj_date = obj_timestamp })
1573 findSummaryBySourceFile :: [ModSummary] -> FilePath -> Maybe ModSummary
1574 findSummaryBySourceFile summaries file
1575 = case [ ms | ms <- summaries, HsSrcFile <- [ms_hsc_src ms],
1576 expectJust "findSummaryBySourceFile" (ml_hs_file (ms_location ms)) == file ] of
1580 -- Summarise a module, and pick up source and timestamp.
1583 -> NodeMap ModSummary -- Map of old summaries
1584 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
1585 -> Located ModuleName -- Imported module to be summarised
1586 -> Maybe (StringBuffer, ClockTime)
1587 -> [ModuleName] -- Modules to exclude
1588 -> IO (Maybe ModSummary) -- Its new summary
1590 summariseModule hsc_env old_summary_map is_boot (L loc wanted_mod) maybe_buf excl_mods
1591 | wanted_mod `elem` excl_mods
1594 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
1595 = do -- Find its new timestamp; all the
1596 -- ModSummaries in the old map have valid ml_hs_files
1597 let location = ms_location old_summary
1598 src_fn = expectJust "summariseModule" (ml_hs_file location)
1600 -- check the modification time on the source file, and
1601 -- return the cached summary if it hasn't changed. If the
1602 -- file has disappeared, we need to call the Finder again.
1604 Just (_,t) -> check_timestamp old_summary location src_fn t
1606 m <- System.IO.Error.try (getModificationTime src_fn)
1608 Right t -> check_timestamp old_summary location src_fn t
1609 Left e | isDoesNotExistError e -> find_it
1610 | otherwise -> ioError e
1612 | otherwise = find_it
1614 dflags = hsc_dflags hsc_env
1616 hsc_src = if is_boot then HsBootFile else HsSrcFile
1618 check_timestamp old_summary location src_fn src_timestamp
1619 | ms_hs_date old_summary == src_timestamp = do
1620 -- update the object-file timestamp
1621 obj_timestamp <- getObjTimestamp location is_boot
1622 return (Just old_summary{ ms_obj_date = obj_timestamp })
1624 -- source changed: re-summarise.
1625 new_summary location (ms_mod old_summary) src_fn src_timestamp
1628 -- Don't use the Finder's cache this time. If the module was
1629 -- previously a package module, it may have now appeared on the
1630 -- search path, so we want to consider it to be a home module. If
1631 -- the module was previously a home module, it may have moved.
1632 uncacheModule hsc_env wanted_mod
1633 found <- findImportedModule hsc_env wanted_mod Nothing
1636 | isJust (ml_hs_file location) ->
1638 just_found location mod
1640 -- Drop external-pkg
1641 ASSERT(modulePackageId mod /= thisPackage dflags)
1645 err -> noModError dflags loc wanted_mod err
1648 just_found location mod = do
1649 -- Adjust location to point to the hs-boot source file,
1650 -- hi file, object file, when is_boot says so
1651 let location' | is_boot = addBootSuffixLocn location
1652 | otherwise = location
1653 src_fn = expectJust "summarise2" (ml_hs_file location')
1655 -- Check that it exists
1656 -- It might have been deleted since the Finder last found it
1657 maybe_t <- modificationTimeIfExists src_fn
1659 Nothing -> noHsFileErr loc src_fn
1660 Just t -> new_summary location' mod src_fn t
1663 new_summary location mod src_fn src_timestamp
1665 -- Preprocess the source file and get its imports
1666 -- The dflags' contains the OPTIONS pragmas
1667 (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn Nothing maybe_buf
1668 (srcimps, the_imps, L mod_loc mod_name) <- getImports dflags' buf hspp_fn
1670 when (mod_name /= wanted_mod) $
1671 throwDyn $ mkPlainErrMsg mod_loc $
1672 text "file name does not match module name"
1673 <+> quotes (ppr mod_name)
1675 -- Find the object timestamp, and return the summary
1676 obj_timestamp <- getObjTimestamp location is_boot
1678 return (Just ( ModSummary { ms_mod = mod,
1679 ms_hsc_src = hsc_src,
1680 ms_location = location,
1681 ms_hspp_file = hspp_fn,
1682 ms_hspp_opts = dflags',
1683 ms_hspp_buf = Just buf,
1684 ms_srcimps = srcimps,
1686 ms_hs_date = src_timestamp,
1687 ms_obj_date = obj_timestamp }))
1690 getObjTimestamp location is_boot
1691 = if is_boot then return Nothing
1692 else modificationTimeIfExists (ml_obj_file location)
1695 preprocessFile :: DynFlags -> FilePath -> Maybe Phase -> Maybe (StringBuffer,ClockTime)
1696 -> IO (DynFlags, FilePath, StringBuffer)
1697 preprocessFile dflags src_fn mb_phase Nothing
1699 (dflags', hspp_fn) <- preprocess dflags (src_fn, mb_phase)
1700 buf <- hGetStringBuffer hspp_fn
1701 return (dflags', hspp_fn, buf)
1703 preprocessFile dflags src_fn mb_phase (Just (buf, time))
1705 -- case we bypass the preprocessing stage?
1707 local_opts = getOptions buf src_fn
1709 (dflags', errs) <- parseDynamicFlags dflags (map unLoc local_opts)
1713 | Just (Unlit _) <- mb_phase = True
1714 | Nothing <- mb_phase, Unlit _ <- startPhase src_fn = True
1715 -- note: local_opts is only required if there's no Unlit phase
1716 | dopt Opt_Cpp dflags' = True
1717 | dopt Opt_Pp dflags' = True
1720 when needs_preprocessing $
1721 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
1723 return (dflags', src_fn, buf)
1726 -----------------------------------------------------------------------------
1728 -----------------------------------------------------------------------------
1730 noModError :: DynFlags -> SrcSpan -> ModuleName -> FindResult -> IO ab
1731 -- ToDo: we don't have a proper line number for this error
1732 noModError dflags loc wanted_mod err
1733 = throwDyn $ mkPlainErrMsg loc $ cannotFindModule dflags wanted_mod err
1735 noHsFileErr loc path
1736 = throwDyn $ mkPlainErrMsg loc $ text "Can't find" <+> text path
1739 = throwDyn $ mkPlainErrMsg noSrcSpan $
1740 text "module" <+> quotes (ppr mod) <+> text "is a package module"
1742 multiRootsErr :: [ModSummary] -> IO ()
1743 multiRootsErr summs@(summ1:_)
1744 = throwDyn $ mkPlainErrMsg noSrcSpan $
1745 text "module" <+> quotes (ppr mod) <+>
1746 text "is defined in multiple files:" <+>
1747 sep (map text files)
1750 files = map (expectJust "checkDup" . ml_hs_file . ms_location) summs
1752 cyclicModuleErr :: [ModSummary] -> SDoc
1754 = hang (ptext SLIT("Module imports form a cycle for modules:"))
1755 2 (vcat (map show_one ms))
1757 show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
1758 nest 2 $ ptext SLIT("imports:") <+>
1759 (pp_imps HsBootFile (ms_srcimps ms)
1760 $$ pp_imps HsSrcFile (ms_imps ms))]
1761 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
1762 pp_imps src mods = fsep (map (show_mod src) mods)
1765 -- | Inform GHC that the working directory has changed. GHC will flush
1766 -- its cache of module locations, since it may no longer be valid.
1767 -- Note: if you change the working directory, you should also unload
1768 -- the current program (set targets to empty, followed by load).
1769 workingDirectoryChanged :: Session -> IO ()
1770 workingDirectoryChanged s = withSession s $ flushFinderCaches
1772 -- -----------------------------------------------------------------------------
1773 -- inspecting the session
1775 -- | Get the module dependency graph.
1776 getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
1777 getModuleGraph s = withSession s (return . hsc_mod_graph)
1779 isLoaded :: Session -> ModuleName -> IO Bool
1780 isLoaded s m = withSession s $ \hsc_env ->
1781 return $! isJust (lookupUFM (hsc_HPT hsc_env) m)
1783 getBindings :: Session -> IO [TyThing]
1784 getBindings s = withSession s $ \hsc_env ->
1785 -- we have to implement the shadowing behaviour of ic_tmp_ids here
1786 -- (see InteractiveContext) and the quickest way is to use an OccEnv.
1788 tmp_ids = ic_tmp_ids (hsc_IC hsc_env)
1789 filtered = foldr f (const []) tmp_ids emptyUniqSet
1791 | uniq `elementOfUniqSet` set = rest set
1792 | otherwise = AnId id : rest (addOneToUniqSet set uniq)
1793 where uniq = getUnique (nameOccName (idName id))
1797 getPrintUnqual :: Session -> IO PrintUnqualified
1798 getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
1800 -- | Container for information about a 'Module'.
1801 data ModuleInfo = ModuleInfo {
1802 minf_type_env :: TypeEnv,
1803 minf_exports :: NameSet, -- ToDo, [AvailInfo] like ModDetails?
1804 minf_rdr_env :: Maybe GlobalRdrEnv, -- Nothing for a compiled/package mod
1805 minf_instances :: [Instance]
1807 ,minf_modBreaks :: ModBreaks
1809 -- ToDo: this should really contain the ModIface too
1811 -- We don't want HomeModInfo here, because a ModuleInfo applies
1812 -- to package modules too.
1814 -- | Request information about a loaded 'Module'
1815 getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
1816 getModuleInfo s mdl = withSession s $ \hsc_env -> do
1817 let mg = hsc_mod_graph hsc_env
1818 if mdl `elem` map ms_mod mg
1819 then getHomeModuleInfo hsc_env (moduleName mdl)
1821 {- if isHomeModule (hsc_dflags hsc_env) mdl
1823 else -} getPackageModuleInfo hsc_env mdl
1824 -- getPackageModuleInfo will attempt to find the interface, so
1825 -- we don't want to call it for a home module, just in case there
1826 -- was a problem loading the module and the interface doesn't
1827 -- exist... hence the isHomeModule test here. (ToDo: reinstate)
1829 getPackageModuleInfo :: HscEnv -> Module -> IO (Maybe ModuleInfo)
1830 getPackageModuleInfo hsc_env mdl = do
1832 (_msgs, mb_avails) <- getModuleExports hsc_env mdl
1834 Nothing -> return Nothing
1836 eps <- readIORef (hsc_EPS hsc_env)
1838 names = availsToNameSet avails
1840 tys = [ ty | name <- concatMap availNames avails,
1841 Just ty <- [lookupTypeEnv pte name] ]
1843 return (Just (ModuleInfo {
1844 minf_type_env = mkTypeEnv tys,
1845 minf_exports = names,
1846 minf_rdr_env = Just $! nameSetToGlobalRdrEnv names (moduleName mdl),
1847 minf_instances = error "getModuleInfo: instances for package module unimplemented",
1848 minf_modBreaks = emptyModBreaks
1851 -- bogusly different for non-GHCI (ToDo)
1855 getHomeModuleInfo hsc_env mdl =
1856 case lookupUFM (hsc_HPT hsc_env) mdl of
1857 Nothing -> return Nothing
1859 let details = hm_details hmi
1860 return (Just (ModuleInfo {
1861 minf_type_env = md_types details,
1862 minf_exports = availsToNameSet (md_exports details),
1863 minf_rdr_env = mi_globals $! hm_iface hmi,
1864 minf_instances = md_insts details
1866 ,minf_modBreaks = md_modBreaks details
1870 -- | The list of top-level entities defined in a module
1871 modInfoTyThings :: ModuleInfo -> [TyThing]
1872 modInfoTyThings minf = typeEnvElts (minf_type_env minf)
1874 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
1875 modInfoTopLevelScope minf
1876 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
1878 modInfoExports :: ModuleInfo -> [Name]
1879 modInfoExports minf = nameSetToList $! minf_exports minf
1881 -- | Returns the instances defined by the specified module.
1882 -- Warning: currently unimplemented for package modules.
1883 modInfoInstances :: ModuleInfo -> [Instance]
1884 modInfoInstances = minf_instances
1886 modInfoIsExportedName :: ModuleInfo -> Name -> Bool
1887 modInfoIsExportedName minf name = elemNameSet name (minf_exports minf)
1889 modInfoPrintUnqualified :: ModuleInfo -> Maybe PrintUnqualified
1890 modInfoPrintUnqualified minf = fmap mkPrintUnqualified (minf_rdr_env minf)
1892 modInfoLookupName :: Session -> ModuleInfo -> Name -> IO (Maybe TyThing)
1893 modInfoLookupName s minf name = withSession s $ \hsc_env -> do
1894 case lookupTypeEnv (minf_type_env minf) name of
1895 Just tyThing -> return (Just tyThing)
1897 eps <- readIORef (hsc_EPS hsc_env)
1898 return $! lookupType (hsc_dflags hsc_env)
1899 (hsc_HPT hsc_env) (eps_PTE eps) name
1902 modInfoModBreaks = minf_modBreaks
1905 isDictonaryId :: Id -> Bool
1907 = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
1909 -- | Looks up a global name: that is, any top-level name in any
1910 -- visible module. Unlike 'lookupName', lookupGlobalName does not use
1911 -- the interactive context, and therefore does not require a preceding
1913 lookupGlobalName :: Session -> Name -> IO (Maybe TyThing)
1914 lookupGlobalName s name = withSession s $ \hsc_env -> do
1915 eps <- readIORef (hsc_EPS hsc_env)
1916 return $! lookupType (hsc_dflags hsc_env)
1917 (hsc_HPT hsc_env) (eps_PTE eps) name
1919 -- -----------------------------------------------------------------------------
1920 -- Misc exported utils
1922 dataConType :: DataCon -> Type
1923 dataConType dc = idType (dataConWrapId dc)
1925 -- | print a 'NamedThing', adding parentheses if the name is an operator.
1926 pprParenSymName :: NamedThing a => a -> SDoc
1927 pprParenSymName a = parenSymOcc (getOccName a) (ppr (getName a))
1929 -- ----------------------------------------------------------------------------
1934 -- - Data and Typeable instances for HsSyn.
1936 -- ToDo: check for small transformations that happen to the syntax in
1937 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
1939 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
1940 -- to get from TyCons, Ids etc. to TH syntax (reify).
1942 -- :browse will use either lm_toplev or inspect lm_interface, depending
1943 -- on whether the module is interpreted or not.
1945 -- This is for reconstructing refactored source code
1946 -- Calls the lexer repeatedly.
1947 -- ToDo: add comment tokens to token stream
1948 getTokenStream :: Session -> Module -> IO [Located Token]
1951 -- -----------------------------------------------------------------------------
1952 -- Interactive evaluation
1954 -- | Takes a 'ModuleName' and possibly a 'PackageId', and consults the
1955 -- filesystem and package database to find the corresponding 'Module',
1956 -- using the algorithm that is used for an @import@ declaration.
1957 findModule :: Session -> ModuleName -> Maybe PackageId -> IO Module
1958 findModule s mod_name maybe_pkg = withSession s $ \hsc_env ->
1959 findModule' hsc_env mod_name maybe_pkg
1961 findModule' hsc_env mod_name maybe_pkg =
1963 dflags = hsc_dflags hsc_env
1964 hpt = hsc_HPT hsc_env
1965 this_pkg = thisPackage dflags
1967 case lookupUFM hpt mod_name of
1968 Just mod_info -> return (mi_module (hm_iface mod_info))
1969 _not_a_home_module -> do
1970 res <- findImportedModule hsc_env mod_name maybe_pkg
1972 Found _ m | modulePackageId m /= this_pkg -> return m
1973 | otherwise -> throwDyn (CmdLineError (showSDoc $
1974 text "module" <+> pprModule m <+>
1975 text "is not loaded"))
1976 err -> let msg = cannotFindModule dflags mod_name err in
1977 throwDyn (CmdLineError (showSDoc msg))
1980 getHistorySpan :: Session -> History -> IO SrcSpan
1981 getHistorySpan sess h = withSession sess $ \hsc_env ->
1982 return$ InteractiveEval.getHistorySpan hsc_env h