1 -- -----------------------------------------------------------------------------
3 -- (c) The University of Glasgow, 2005
7 -- -----------------------------------------------------------------------------
13 defaultCleanupHandler,
16 -- * Flags and settings
17 DynFlags(..), DynFlag(..), Severity(..), HscTarget(..), dopt,
18 GhcMode(..), GhcLink(..),
24 Target(..), TargetId(..), Phase,
31 -- * Extending the program scope
32 extendGlobalRdrScope, -- :: Session -> [GlobalRdrElt] -> IO ()
33 setGlobalRdrScope, -- :: Session -> [GlobalRdrElt] -> IO ()
34 extendGlobalTypeScope, -- :: Session -> [Id] -> IO ()
35 setGlobalTypeScope, -- :: Session -> [Id] -> IO ()
37 -- * Loading\/compiling the program
39 load, LoadHowMuch(..), SuccessFlag(..), -- also does depanal
40 workingDirectoryChanged,
41 checkModule, CheckedModule(..),
42 TypecheckedSource, ParsedSource, RenamedSource,
44 -- * Parsing Haddock comments
47 -- * Inspecting the module structure of the program
48 ModuleGraph, ModSummary(..), ms_mod_name, ModLocation(..),
53 -- * Inspecting modules
58 modInfoPrintUnqualified,
61 modInfoIsExportedName,
66 PrintUnqualified, alwaysQualify,
68 -- * Interactive evaluation
69 getBindings, getPrintUnqual,
72 setContext, getContext,
81 runStmt, stepStmt, -- traceStmt,
82 resume, stepResume, -- traceResume,
83 Resume(resumeStmt, resumeThreadId, resumeBreakInfo, resumeSpan),
88 compileExpr, HValue, dynCompileExpr,
90 obtainTerm, obtainTerm1,
92 ModBreaks(..), BreakIndex,
93 BreakInfo(breakInfo_number, breakInfo_module),
94 BreakArray, setBreakOn, setBreakOff, getBreak,
97 -- * Abstract syntax elements
103 Module, mkModule, pprModule, moduleName, modulePackageId,
104 ModuleName, mkModuleName, moduleNameString,
108 nameModule, pprParenSymName, nameSrcLoc,
110 RdrName(Qual,Unqual),
114 isImplicitId, isDeadBinder,
115 isExportedId, isLocalId, isGlobalId,
117 isPrimOpId, isFCallId, isClassOpId_maybe,
118 isDataConWorkId, idDataCon,
119 isBottomingId, isDictonaryId,
120 recordSelectorFieldLabel,
122 -- ** Type constructors
124 tyConTyVars, tyConDataCons, tyConArity,
125 isClassTyCon, isSynTyCon, isNewTyCon, isPrimTyCon, isFunTyCon,
127 synTyConDefn, synTyConType, synTyConResKind,
133 -- ** Data constructors
135 dataConSig, dataConType, dataConTyCon, dataConFieldLabels,
136 dataConIsInfix, isVanillaDataCon,
138 StrictnessMark(..), isMarkedStrict,
142 classMethods, classSCTheta, classTvsFds,
147 instanceDFunId, pprInstance, pprInstanceHdr,
149 -- ** Types and Kinds
150 Type, dropForAlls, splitForAllTys, funResultTy,
151 pprParendType, pprTypeApp,
154 ThetaType, pprThetaArrow,
160 module HsSyn, -- ToDo: remove extraneous bits
164 defaultFixity, maxPrecedence,
168 -- ** Source locations
170 mkSrcLoc, isGoodSrcLoc,
171 srcLocFile, srcLocLine, srcLocCol,
173 mkSrcSpan, srcLocSpan,
174 srcSpanStart, srcSpanEnd,
176 srcSpanStartLine, srcSpanEndLine,
177 srcSpanStartCol, srcSpanEndCol,
180 GhcException(..), showGhcException,
190 * inline bits of HscMain here to simplify layering: hscTcExpr, hscStmt.
191 * what StaticFlags should we expose, if any?
194 #include "HsVersions.h"
197 import qualified Linker
198 import Linker ( HValue )
203 import InteractiveEval
210 import Type hiding (typeKind)
211 import TcType hiding (typeKind)
213 import Var hiding (setIdType)
214 import TysPrim ( alphaTyVars )
219 import Name hiding ( varName )
220 import OccName ( parenSymOcc )
221 import InstEnv ( Instance, instanceDFunId, pprInstance, pprInstanceHdr )
223 import DriverPipeline
224 import DriverPhases ( Phase(..), isHaskellSrcFilename, startPhase )
225 import HeaderInfo ( getImports, getOptions )
227 import HscMain ( newHscEnv, hscFileCheck, HscChecked(..) )
230 import SysTools ( initSysTools, cleanTempFiles, cleanTempFilesExcept,
238 import Bag ( unitBag, listToBag )
239 import ErrUtils ( Severity(..), showPass, fatalErrorMsg, debugTraceMsg,
240 mkPlainErrMsg, printBagOfErrors, printBagOfWarnings,
242 import qualified ErrUtils
244 import StringBuffer ( StringBuffer, hGetStringBuffer )
247 import Maybes ( expectJust, mapCatMaybes )
249 import HaddockLex ( tokenise )
251 import Control.Concurrent
252 import System.Directory ( getModificationTime, doesFileExist )
255 import qualified Data.List as List
257 import System.Exit ( exitWith, ExitCode(..) )
258 import System.Time ( ClockTime )
259 import Control.Exception as Exception hiding (handle)
262 import System.IO.Error ( isDoesNotExistError )
263 import Prelude hiding (init)
265 #if __GLASGOW_HASKELL__ < 600
266 import System.IO as System.IO.Error ( try )
268 import System.IO.Error ( try )
271 -- -----------------------------------------------------------------------------
272 -- Exception handlers
274 -- | Install some default exception handlers and run the inner computation.
275 -- Unless you want to handle exceptions yourself, you should wrap this around
276 -- the top level of your program. The default handlers output the error
277 -- message(s) to stderr and exit cleanly.
278 defaultErrorHandler :: DynFlags -> IO a -> IO a
279 defaultErrorHandler dflags inner =
280 -- top-level exception handler: any unrecognised exception is a compiler bug.
281 handle (\exception -> do
284 -- an IO exception probably isn't our fault, so don't panic
286 fatalErrorMsg dflags (text (show exception))
287 AsyncException StackOverflow ->
288 fatalErrorMsg dflags (text "stack overflow: use +RTS -K<size> to increase it")
290 fatalErrorMsg dflags (text (show (Panic (show exception))))
291 exitWith (ExitFailure 1)
294 -- program errors: messages with locations attached. Sometimes it is
295 -- convenient to just throw these as exceptions.
296 handleDyn (\dyn -> do printBagOfErrors dflags (unitBag dyn)
297 exitWith (ExitFailure 1)) $
299 -- error messages propagated as exceptions
300 handleDyn (\dyn -> do
303 PhaseFailed _ code -> exitWith code
304 Interrupted -> exitWith (ExitFailure 1)
305 _ -> do fatalErrorMsg dflags (text (show (dyn :: GhcException)))
306 exitWith (ExitFailure 1)
310 -- | Install a default cleanup handler to remove temporary files
311 -- deposited by a GHC run. This is seperate from
312 -- 'defaultErrorHandler', because you might want to override the error
313 -- handling, but still get the ordinary cleanup behaviour.
314 defaultCleanupHandler :: DynFlags -> IO a -> IO a
315 defaultCleanupHandler dflags inner =
316 -- make sure we clean up after ourselves
317 later (do cleanTempFiles dflags
320 -- exceptions will be blocked while we clean the temporary files,
321 -- so there shouldn't be any difficulty if we receive further
326 -- | Starts a new session. A session consists of a set of loaded
327 -- modules, a set of options (DynFlags), and an interactive context.
328 newSession :: Maybe FilePath -> IO Session
329 newSession mb_top_dir = do
331 main_thread <- myThreadId
332 modifyMVar_ interruptTargetThread (return . (main_thread :))
333 installSignalHandlers
335 dflags0 <- initSysTools mb_top_dir defaultDynFlags
336 dflags <- initDynFlags dflags0
337 env <- newHscEnv dflags
341 -- tmp: this breaks the abstraction, but required because DriverMkDepend
342 -- needs to call the Finder. ToDo: untangle this.
343 sessionHscEnv :: Session -> IO HscEnv
344 sessionHscEnv (Session ref) = readIORef ref
346 -- -----------------------------------------------------------------------------
349 -- | Grabs the DynFlags from the Session
350 getSessionDynFlags :: Session -> IO DynFlags
351 getSessionDynFlags s = withSession s (return . hsc_dflags)
353 -- | Updates the DynFlags in a Session. This also reads
354 -- the package database (unless it has already been read),
355 -- and prepares the compilers knowledge about packages. It
356 -- can be called again to load new packages: just add new
357 -- package flags to (packageFlags dflags).
359 -- Returns a list of new packages that may need to be linked in using
360 -- the dynamic linker (see 'linkPackages') as a result of new package
361 -- flags. If you are not doing linking or doing static linking, you
362 -- can ignore the list of packages returned.
364 setSessionDynFlags :: Session -> DynFlags -> IO [PackageId]
365 setSessionDynFlags (Session ref) dflags = do
366 hsc_env <- readIORef ref
367 (dflags', preload) <- initPackages dflags
368 writeIORef ref $! hsc_env{ hsc_dflags = dflags' }
371 -- | If there is no -o option, guess the name of target executable
372 -- by using top-level source file name as a base.
373 guessOutputFile :: Session -> IO ()
374 guessOutputFile s = modifySession s $ \env ->
375 let dflags = hsc_dflags env
376 mod_graph = hsc_mod_graph env
377 mainModuleSrcPath, guessedName :: Maybe String
378 mainModuleSrcPath = do
379 let isMain = (== mainModIs dflags) . ms_mod
380 [ms] <- return (filter isMain mod_graph)
381 ml_hs_file (ms_location ms)
382 guessedName = fmap basenameOf mainModuleSrcPath
384 case outputFile dflags of
386 Nothing -> env { hsc_dflags = dflags { outputFile = guessedName } }
388 -- -----------------------------------------------------------------------------
391 -- ToDo: think about relative vs. absolute file paths. And what
392 -- happens when the current directory changes.
394 -- | Sets the targets for this session. Each target may be a module name
395 -- or a filename. The targets correspond to the set of root modules for
396 -- the program\/library. Unloading the current program is achieved by
397 -- setting the current set of targets to be empty, followed by load.
398 setTargets :: Session -> [Target] -> IO ()
399 setTargets s targets = modifySession s (\h -> h{ hsc_targets = targets })
401 -- | returns the current set of targets
402 getTargets :: Session -> IO [Target]
403 getTargets s = withSession s (return . hsc_targets)
405 -- | Add another target
406 addTarget :: Session -> Target -> IO ()
408 = modifySession s (\h -> h{ hsc_targets = target : hsc_targets h })
411 removeTarget :: Session -> TargetId -> IO ()
412 removeTarget s target_id
413 = modifySession s (\h -> h{ hsc_targets = filter (hsc_targets h) })
415 filter targets = [ t | t@(Target id _) <- targets, id /= target_id ]
417 -- Attempts to guess what Target a string refers to. This function implements
418 -- the --make/GHCi command-line syntax for filenames:
420 -- - if the string looks like a Haskell source filename, then interpret
422 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
424 -- - otherwise interpret the string as a module name
426 guessTarget :: String -> Maybe Phase -> IO Target
427 guessTarget file (Just phase)
428 = return (Target (TargetFile file (Just phase)) Nothing)
429 guessTarget file Nothing
430 | isHaskellSrcFilename file
431 = return (Target (TargetFile file Nothing) Nothing)
433 = do exists <- doesFileExist hs_file
435 then return (Target (TargetFile hs_file Nothing) Nothing)
437 exists <- doesFileExist lhs_file
439 then return (Target (TargetFile lhs_file Nothing) Nothing)
441 return (Target (TargetModule (mkModuleName file)) Nothing)
443 hs_file = file `joinFileExt` "hs"
444 lhs_file = file `joinFileExt` "lhs"
446 -- -----------------------------------------------------------------------------
447 -- Extending the program scope
449 extendGlobalRdrScope :: Session -> [GlobalRdrElt] -> IO ()
450 extendGlobalRdrScope session rdrElts
451 = modifySession session $ \hscEnv ->
452 let global_rdr = hsc_global_rdr_env hscEnv
453 in hscEnv{ hsc_global_rdr_env = foldl extendGlobalRdrEnv global_rdr rdrElts }
455 setGlobalRdrScope :: Session -> [GlobalRdrElt] -> IO ()
456 setGlobalRdrScope session rdrElts
457 = modifySession session $ \hscEnv ->
458 hscEnv{ hsc_global_rdr_env = foldl extendGlobalRdrEnv emptyGlobalRdrEnv rdrElts }
460 extendGlobalTypeScope :: Session -> [Id] -> IO ()
461 extendGlobalTypeScope session ids
462 = modifySession session $ \hscEnv ->
463 let global_type = hsc_global_type_env hscEnv
464 in hscEnv{ hsc_global_type_env = extendTypeEnvWithIds global_type ids }
466 setGlobalTypeScope :: Session -> [Id] -> IO ()
467 setGlobalTypeScope session ids
468 = modifySession session $ \hscEnv ->
469 hscEnv{ hsc_global_type_env = extendTypeEnvWithIds emptyTypeEnv ids }
471 -- -----------------------------------------------------------------------------
472 -- Parsing Haddock comments
474 parseHaddockComment :: String -> Either String (HsDoc RdrName)
475 parseHaddockComment string = parseHaddockParagraphs (tokenise string)
477 -- -----------------------------------------------------------------------------
478 -- Loading the program
480 -- Perform a dependency analysis starting from the current targets
481 -- and update the session with the new module graph.
482 depanal :: Session -> [ModuleName] -> Bool -> IO (Maybe ModuleGraph)
483 depanal (Session ref) excluded_mods allow_dup_roots = do
484 hsc_env <- readIORef ref
486 dflags = hsc_dflags hsc_env
487 targets = hsc_targets hsc_env
488 old_graph = hsc_mod_graph hsc_env
490 showPass dflags "Chasing dependencies"
491 debugTraceMsg dflags 2 (hcat [
492 text "Chasing modules from: ",
493 hcat (punctuate comma (map pprTarget targets))])
495 r <- downsweep hsc_env old_graph excluded_mods allow_dup_roots
497 Just mod_graph -> writeIORef ref hsc_env{ hsc_mod_graph = mod_graph }
502 -- | The result of load.
504 = LoadOk Errors -- ^ all specified targets were loaded successfully.
505 | LoadFailed Errors -- ^ not all modules were loaded.
507 type Errors = [String]
509 data ErrMsg = ErrMsg {
510 errMsgSeverity :: Severity, -- warning, error, etc.
511 errMsgSpans :: [SrcSpan],
512 errMsgShortDoc :: Doc,
513 errMsgExtraInfo :: Doc
519 | LoadUpTo ModuleName
520 | LoadDependenciesOf ModuleName
522 -- | Try to load the program. If a Module is supplied, then just
523 -- attempt to load up to this target. If no Module is supplied,
524 -- then try to load all targets.
525 load :: Session -> LoadHowMuch -> IO SuccessFlag
526 load s@(Session ref) how_much
528 -- Dependency analysis first. Note that this fixes the module graph:
529 -- even if we don't get a fully successful upsweep, the full module
530 -- graph is still retained in the Session. We can tell which modules
531 -- were successfully loaded by inspecting the Session's HPT.
532 mb_graph <- depanal s [] False
534 Just mod_graph -> load2 s how_much mod_graph
535 Nothing -> return Failed
537 load2 s@(Session ref) how_much mod_graph = do
539 hsc_env <- readIORef ref
541 let hpt1 = hsc_HPT hsc_env
542 let dflags = hsc_dflags hsc_env
544 -- The "bad" boot modules are the ones for which we have
545 -- B.hs-boot in the module graph, but no B.hs
546 -- The downsweep should have ensured this does not happen
548 let all_home_mods = [ms_mod_name s
549 | s <- mod_graph, not (isBootSummary s)]
551 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
552 not (ms_mod_name s `elem` all_home_mods)]
554 ASSERT( null bad_boot_mods ) return ()
556 -- mg2_with_srcimps drops the hi-boot nodes, returning a
557 -- graph with cycles. Among other things, it is used for
558 -- backing out partially complete cycles following a failed
559 -- upsweep, and for removing from hpt all the modules
560 -- not in strict downwards closure, during calls to compile.
561 let mg2_with_srcimps :: [SCC ModSummary]
562 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
564 -- If we can determine that any of the {-# SOURCE #-} imports
565 -- are definitely unnecessary, then emit a warning.
566 warnUnnecessarySourceImports dflags mg2_with_srcimps
569 -- check the stability property for each module.
570 stable_mods@(stable_obj,stable_bco)
571 = checkStability hpt1 mg2_with_srcimps all_home_mods
573 -- prune bits of the HPT which are definitely redundant now,
575 pruned_hpt = pruneHomePackageTable hpt1
576 (flattenSCCs mg2_with_srcimps)
581 debugTraceMsg dflags 2 (text "Stable obj:" <+> ppr stable_obj $$
582 text "Stable BCO:" <+> ppr stable_bco)
584 -- Unload any modules which are going to be re-linked this time around.
585 let stable_linkables = [ linkable
586 | m <- stable_obj++stable_bco,
587 Just hmi <- [lookupUFM pruned_hpt m],
588 Just linkable <- [hm_linkable hmi] ]
589 unload hsc_env stable_linkables
591 -- We could at this point detect cycles which aren't broken by
592 -- a source-import, and complain immediately, but it seems better
593 -- to let upsweep_mods do this, so at least some useful work gets
594 -- done before the upsweep is abandoned.
595 --hPutStrLn stderr "after tsort:\n"
596 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
598 -- Now do the upsweep, calling compile for each module in
599 -- turn. Final result is version 3 of everything.
601 -- Topologically sort the module graph, this time including hi-boot
602 -- nodes, and possibly just including the portion of the graph
603 -- reachable from the module specified in the 2nd argument to load.
604 -- This graph should be cycle-free.
605 -- If we're restricting the upsweep to a portion of the graph, we
606 -- also want to retain everything that is still stable.
607 let full_mg :: [SCC ModSummary]
608 full_mg = topSortModuleGraph False mod_graph Nothing
610 maybe_top_mod = case how_much of
612 LoadDependenciesOf m -> Just m
615 partial_mg0 :: [SCC ModSummary]
616 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
618 -- LoadDependenciesOf m: we want the upsweep to stop just
619 -- short of the specified module (unless the specified module
622 | LoadDependenciesOf mod <- how_much
623 = ASSERT( case last partial_mg0 of
624 AcyclicSCC ms -> ms_mod_name ms == mod; _ -> False )
625 List.init partial_mg0
631 | AcyclicSCC ms <- full_mg,
632 ms_mod_name ms `elem` stable_obj++stable_bco,
633 ms_mod_name ms `notElem` [ ms_mod_name ms' |
634 AcyclicSCC ms' <- partial_mg ] ]
636 mg = stable_mg ++ partial_mg
638 -- clean up between compilations
639 let cleanup = cleanTempFilesExcept dflags
640 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
642 debugTraceMsg dflags 2 (hang (text "Ready for upsweep")
644 (upsweep_ok, hsc_env1, modsUpswept)
645 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
646 pruned_hpt stable_mods cleanup mg
648 -- Make modsDone be the summaries for each home module now
649 -- available; this should equal the domain of hpt3.
650 -- Get in in a roughly top .. bottom order (hence reverse).
652 let modsDone = reverse modsUpswept
654 -- Try and do linking in some form, depending on whether the
655 -- upsweep was completely or only partially successful.
657 if succeeded upsweep_ok
660 -- Easy; just relink it all.
661 do debugTraceMsg dflags 2 (text "Upsweep completely successful.")
663 -- Clean up after ourselves
664 cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
666 -- Issue a warning for the confusing case where the user
667 -- said '-o foo' but we're not going to do any linking.
668 -- We attempt linking if either (a) one of the modules is
669 -- called Main, or (b) the user said -no-hs-main, indicating
670 -- that main() is going to come from somewhere else.
672 let ofile = outputFile dflags
673 let no_hs_main = dopt Opt_NoHsMain dflags
675 main_mod = mainModIs dflags
676 a_root_is_Main = any ((==main_mod).ms_mod) mod_graph
677 do_linking = a_root_is_Main || no_hs_main
679 when (ghcLink dflags == LinkBinary
680 && isJust ofile && not do_linking) $
681 debugTraceMsg dflags 1 $
682 text ("Warning: output was redirected with -o, " ++
683 "but no output will be generated\n" ++
684 "because there is no " ++
685 moduleNameString (moduleName main_mod) ++ " module.")
687 -- link everything together
688 linkresult <- link (ghcLink dflags) dflags do_linking (hsc_HPT hsc_env1)
690 loadFinish Succeeded linkresult ref hsc_env1
693 -- Tricky. We need to back out the effects of compiling any
694 -- half-done cycles, both so as to clean up the top level envs
695 -- and to avoid telling the interactive linker to link them.
696 do debugTraceMsg dflags 2 (text "Upsweep partially successful.")
699 = map ms_mod modsDone
700 let mods_to_zap_names
701 = findPartiallyCompletedCycles modsDone_names
704 = filter ((`notElem` mods_to_zap_names).ms_mod)
707 let hpt4 = retainInTopLevelEnvs (map ms_mod_name mods_to_keep)
710 -- Clean up after ourselves
711 cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
713 -- there should be no Nothings where linkables should be, now
714 ASSERT(all (isJust.hm_linkable)
715 (eltsUFM (hsc_HPT hsc_env))) do
717 -- Link everything together
718 linkresult <- link (ghcLink dflags) dflags False hpt4
720 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
721 loadFinish Failed linkresult ref hsc_env4
723 -- Finish up after a load.
725 -- If the link failed, unload everything and return.
726 loadFinish all_ok Failed ref hsc_env
727 = do unload hsc_env []
728 writeIORef ref $! discardProg hsc_env
731 -- Empty the interactive context and set the module context to the topmost
732 -- newly loaded module, or the Prelude if none were loaded.
733 loadFinish all_ok Succeeded ref hsc_env
734 = do writeIORef ref $! hsc_env{ hsc_IC = emptyInteractiveContext }
738 -- Forget the current program, but retain the persistent info in HscEnv
739 discardProg :: HscEnv -> HscEnv
741 = hsc_env { hsc_mod_graph = emptyMG,
742 hsc_IC = emptyInteractiveContext,
743 hsc_HPT = emptyHomePackageTable }
745 -- used to fish out the preprocess output files for the purposes of
746 -- cleaning up. The preprocessed file *might* be the same as the
747 -- source file, but that doesn't do any harm.
748 ppFilesFromSummaries summaries = map ms_hspp_file summaries
750 -- -----------------------------------------------------------------------------
754 CheckedModule { parsedSource :: ParsedSource,
755 renamedSource :: Maybe RenamedSource,
756 typecheckedSource :: Maybe TypecheckedSource,
757 checkedModuleInfo :: Maybe ModuleInfo
759 -- ToDo: improvements that could be made here:
760 -- if the module succeeded renaming but not typechecking,
761 -- we can still get back the GlobalRdrEnv and exports, so
762 -- perhaps the ModuleInfo should be split up into separate
763 -- fields within CheckedModule.
765 type ParsedSource = Located (HsModule RdrName)
766 type RenamedSource = (HsGroup Name, [LImportDecl Name], Maybe [LIE Name],
767 Maybe (HsDoc Name), HaddockModInfo Name)
768 type TypecheckedSource = LHsBinds Id
771 -- - things that aren't in the output of the typechecker right now:
775 -- - type/data/newtype declarations
776 -- - class declarations
778 -- - extra things in the typechecker's output:
779 -- - default methods are turned into top-level decls.
780 -- - dictionary bindings
783 -- | This is the way to get access to parsed and typechecked source code
784 -- for a module. 'checkModule' loads all the dependencies of the specified
785 -- module in the Session, and then attempts to typecheck the module. If
786 -- successful, it returns the abstract syntax for the module.
787 checkModule :: Session -> ModuleName -> IO (Maybe CheckedModule)
788 checkModule session@(Session ref) mod = do
789 -- load up the dependencies first
790 r <- load session (LoadDependenciesOf mod)
791 if (failed r) then return Nothing else do
793 -- now parse & typecheck the module
794 hsc_env <- readIORef ref
795 let mg = hsc_mod_graph hsc_env
796 case [ ms | ms <- mg, ms_mod_name ms == mod ] of
799 mbChecked <- hscFileCheck hsc_env{hsc_dflags=ms_hspp_opts ms} ms
801 Nothing -> return Nothing
802 Just (HscChecked parsed renamed Nothing) ->
803 return (Just (CheckedModule {
804 parsedSource = parsed,
805 renamedSource = renamed,
806 typecheckedSource = Nothing,
807 checkedModuleInfo = Nothing }))
808 Just (HscChecked parsed renamed
809 (Just (tc_binds, rdr_env, details))) -> do
810 let minf = ModuleInfo {
811 minf_type_env = md_types details,
812 minf_exports = availsToNameSet $
814 minf_rdr_env = Just rdr_env,
815 minf_instances = md_insts details
817 ,minf_modBreaks = emptyModBreaks
820 return (Just (CheckedModule {
821 parsedSource = parsed,
822 renamedSource = renamed,
823 typecheckedSource = Just tc_binds,
824 checkedModuleInfo = Just minf }))
826 -- ---------------------------------------------------------------------------
829 unload :: HscEnv -> [Linkable] -> IO ()
830 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
831 = case ghcLink (hsc_dflags hsc_env) of
833 LinkInMemory -> Linker.unload (hsc_dflags hsc_env) stable_linkables
835 LinkInMemory -> panic "unload: no interpreter"
839 -- -----------------------------------------------------------------------------
843 Stability tells us which modules definitely do not need to be recompiled.
844 There are two main reasons for having stability:
846 - avoid doing a complete upsweep of the module graph in GHCi when
847 modules near the bottom of the tree have not changed.
849 - to tell GHCi when it can load object code: we can only load object code
850 for a module when we also load object code fo all of the imports of the
851 module. So we need to know that we will definitely not be recompiling
852 any of these modules, and we can use the object code.
854 The stability check is as follows. Both stableObject and
855 stableBCO are used during the upsweep phase later.
858 stable m = stableObject m || stableBCO m
861 all stableObject (imports m)
862 && old linkable does not exist, or is == on-disk .o
863 && date(on-disk .o) > date(.hs)
866 all stable (imports m)
867 && date(BCO) > date(.hs)
870 These properties embody the following ideas:
872 - if a module is stable, then:
873 - if it has been compiled in a previous pass (present in HPT)
874 then it does not need to be compiled or re-linked.
875 - if it has not been compiled in a previous pass,
876 then we only need to read its .hi file from disk and
877 link it to produce a ModDetails.
879 - if a modules is not stable, we will definitely be at least
880 re-linking, and possibly re-compiling it during the upsweep.
881 All non-stable modules can (and should) therefore be unlinked
884 - Note that objects are only considered stable if they only depend
885 on other objects. We can't link object code against byte code.
889 :: HomePackageTable -- HPT from last compilation
890 -> [SCC ModSummary] -- current module graph (cyclic)
891 -> [ModuleName] -- all home modules
892 -> ([ModuleName], -- stableObject
893 [ModuleName]) -- stableBCO
895 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
897 checkSCC (stable_obj, stable_bco) scc0
898 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
899 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
900 | otherwise = (stable_obj, stable_bco)
902 scc = flattenSCC scc0
903 scc_mods = map ms_mod_name scc
904 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
906 scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
907 -- all imports outside the current SCC, but in the home pkg
909 stable_obj_imps = map (`elem` stable_obj) scc_allimps
910 stable_bco_imps = map (`elem` stable_bco) scc_allimps
917 and (zipWith (||) stable_obj_imps stable_bco_imps)
921 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
925 same_as_prev t = case lookupUFM hpt (ms_mod_name ms) of
926 Just hmi | Just l <- hm_linkable hmi
927 -> isObjectLinkable l && t == linkableTime l
929 -- why '>=' rather than '>' above? If the filesystem stores
930 -- times to the nearset second, we may occasionally find that
931 -- the object & source have the same modification time,
932 -- especially if the source was automatically generated
933 -- and compiled. Using >= is slightly unsafe, but it matches
937 = case lookupUFM hpt (ms_mod_name ms) of
938 Just hmi | Just l <- hm_linkable hmi ->
939 not (isObjectLinkable l) &&
940 linkableTime l >= ms_hs_date ms
943 ms_allimps :: ModSummary -> [ModuleName]
944 ms_allimps ms = map unLoc (ms_srcimps ms ++ ms_imps ms)
946 -- -----------------------------------------------------------------------------
947 -- Prune the HomePackageTable
949 -- Before doing an upsweep, we can throw away:
951 -- - For non-stable modules:
952 -- - all ModDetails, all linked code
953 -- - all unlinked code that is out of date with respect to
956 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
957 -- space at the end of the upsweep, because the topmost ModDetails of the
958 -- old HPT holds on to the entire type environment from the previous
961 pruneHomePackageTable
964 -> ([ModuleName],[ModuleName])
967 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
970 | is_stable modl = hmi'
971 | otherwise = hmi'{ hm_details = emptyModDetails }
973 modl = moduleName (mi_module (hm_iface hmi))
974 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
975 = hmi{ hm_linkable = Nothing }
978 where ms = expectJust "prune" (lookupUFM ms_map modl)
980 ms_map = listToUFM [(ms_mod_name ms, ms) | ms <- summ]
982 is_stable m = m `elem` stable_obj || m `elem` stable_bco
984 -- -----------------------------------------------------------------------------
986 -- Return (names of) all those in modsDone who are part of a cycle
987 -- as defined by theGraph.
988 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
989 findPartiallyCompletedCycles modsDone theGraph
993 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
994 chew ((CyclicSCC vs):rest)
995 = let names_in_this_cycle = nub (map ms_mod vs)
997 = nub ([done | done <- modsDone,
998 done `elem` names_in_this_cycle])
999 chewed_rest = chew rest
1001 if notNull mods_in_this_cycle
1002 && length mods_in_this_cycle < length names_in_this_cycle
1003 then mods_in_this_cycle ++ chewed_rest
1006 -- -----------------------------------------------------------------------------
1009 -- This is where we compile each module in the module graph, in a pass
1010 -- from the bottom to the top of the graph.
1012 -- There better had not be any cyclic groups here -- we check for them.
1015 :: HscEnv -- Includes initially-empty HPT
1016 -> HomePackageTable -- HPT from last time round (pruned)
1017 -> ([ModuleName],[ModuleName]) -- stable modules (see checkStability)
1018 -> IO () -- How to clean up unwanted tmp files
1019 -> [SCC ModSummary] -- Mods to do (the worklist)
1021 HscEnv, -- With an updated HPT
1022 [ModSummary]) -- Mods which succeeded
1024 upsweep hsc_env old_hpt stable_mods cleanup mods
1025 = upsweep' hsc_env old_hpt stable_mods cleanup mods 1 (length mods)
1027 upsweep' hsc_env old_hpt stable_mods cleanup
1029 = return (Succeeded, hsc_env, [])
1031 upsweep' hsc_env old_hpt stable_mods cleanup
1032 (CyclicSCC ms:_) _ _
1033 = do fatalErrorMsg (hsc_dflags hsc_env) (cyclicModuleErr ms)
1034 return (Failed, hsc_env, [])
1036 upsweep' hsc_env old_hpt stable_mods cleanup
1037 (AcyclicSCC mod:mods) mod_index nmods
1038 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
1039 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
1040 -- (moduleEnvElts (hsc_HPT hsc_env)))
1042 mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods mod
1045 cleanup -- Remove unwanted tmp files between compilations
1048 Nothing -> return (Failed, hsc_env, [])
1050 { let this_mod = ms_mod_name mod
1052 -- Add new info to hsc_env
1053 hpt1 = addToUFM (hsc_HPT hsc_env) this_mod mod_info
1054 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
1056 -- Space-saving: delete the old HPT entry
1057 -- for mod BUT if mod is a hs-boot
1058 -- node, don't delete it. For the
1059 -- interface, the HPT entry is probaby for the
1060 -- main Haskell source file. Deleting it
1061 -- would force .. (what?? --SDM)
1062 old_hpt1 | isBootSummary mod = old_hpt
1063 | otherwise = delFromUFM old_hpt this_mod
1065 ; (restOK, hsc_env2, modOKs)
1066 <- upsweep' hsc_env1 old_hpt1 stable_mods cleanup
1067 mods (mod_index+1) nmods
1068 ; return (restOK, hsc_env2, mod:modOKs)
1072 -- Compile a single module. Always produce a Linkable for it if
1073 -- successful. If no compilation happened, return the old Linkable.
1074 upsweep_mod :: HscEnv
1076 -> ([ModuleName],[ModuleName])
1078 -> Int -- index of module
1079 -> Int -- total number of modules
1080 -> IO (Maybe HomeModInfo) -- Nothing => Failed
1082 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) summary mod_index nmods
1084 this_mod_name = ms_mod_name summary
1085 this_mod = ms_mod summary
1086 mb_obj_date = ms_obj_date summary
1087 obj_fn = ml_obj_file (ms_location summary)
1088 hs_date = ms_hs_date summary
1090 is_stable_obj = this_mod_name `elem` stable_obj
1091 is_stable_bco = this_mod_name `elem` stable_bco
1093 old_hmi = lookupUFM old_hpt this_mod_name
1095 -- We're using the dflags for this module now, obtained by
1096 -- applying any options in its LANGUAGE & OPTIONS_GHC pragmas.
1097 dflags = ms_hspp_opts summary
1098 prevailing_target = hscTarget (hsc_dflags hsc_env)
1099 local_target = hscTarget dflags
1101 -- If OPTIONS_GHC contains -fasm or -fvia-C, be careful that
1102 -- we don't do anything dodgy: these should only work to change
1103 -- from -fvia-C to -fasm and vice-versa, otherwise we could
1104 -- end up trying to link object code to byte code.
1105 target = if prevailing_target /= local_target
1106 && (not (isObjectTarget prevailing_target)
1107 || not (isObjectTarget local_target))
1108 then prevailing_target
1111 -- store the corrected hscTarget into the summary
1112 summary' = summary{ ms_hspp_opts = dflags { hscTarget = target } }
1114 -- The old interface is ok if
1115 -- a) we're compiling a source file, and the old HPT
1116 -- entry is for a source file
1117 -- b) we're compiling a hs-boot file
1118 -- Case (b) allows an hs-boot file to get the interface of its
1119 -- real source file on the second iteration of the compilation
1120 -- manager, but that does no harm. Otherwise the hs-boot file
1121 -- will always be recompiled
1126 Just hm_info | isBootSummary summary -> Just iface
1127 | not (mi_boot iface) -> Just iface
1128 | otherwise -> Nothing
1130 iface = hm_iface hm_info
1132 compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
1133 compile_it = upsweep_compile hsc_env old_hpt this_mod_name
1134 summary' mod_index nmods mb_old_iface
1136 compile_it_discard_iface
1137 = upsweep_compile hsc_env old_hpt this_mod_name
1138 summary' mod_index nmods Nothing
1144 -- Regardless of whether we're generating object code or
1145 -- byte code, we can always use an existing object file
1146 -- if it is *stable* (see checkStability).
1147 | is_stable_obj, isJust old_hmi ->
1149 -- object is stable, and we have an entry in the
1150 -- old HPT: nothing to do
1152 | is_stable_obj, isNothing old_hmi -> do
1153 linkable <- findObjectLinkable this_mod obj_fn
1154 (expectJust "upseep1" mb_obj_date)
1155 compile_it (Just linkable)
1156 -- object is stable, but we need to load the interface
1157 -- off disk to make a HMI.
1161 ASSERT(isJust old_hmi) -- must be in the old_hpt
1163 -- BCO is stable: nothing to do
1165 | Just hmi <- old_hmi,
1166 Just l <- hm_linkable hmi, not (isObjectLinkable l),
1167 linkableTime l >= ms_hs_date summary ->
1169 -- we have an old BCO that is up to date with respect
1170 -- to the source: do a recompilation check as normal.
1174 -- no existing code at all: we must recompile.
1176 -- When generating object code, if there's an up-to-date
1177 -- object file on the disk, then we can use it.
1178 -- However, if the object file is new (compared to any
1179 -- linkable we had from a previous compilation), then we
1180 -- must discard any in-memory interface, because this
1181 -- means the user has compiled the source file
1182 -- separately and generated a new interface, that we must
1183 -- read from the disk.
1185 obj | isObjectTarget obj,
1186 Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
1189 | Just l <- hm_linkable hmi,
1190 isObjectLinkable l && linkableTime l == obj_date
1191 -> compile_it (Just l)
1193 linkable <- findObjectLinkable this_mod obj_fn obj_date
1194 compile_it_discard_iface (Just linkable)
1200 -- Run hsc to compile a module
1201 upsweep_compile hsc_env old_hpt this_mod summary
1206 compresult <- compile hsc_env summary mb_old_linkable mb_old_iface
1210 -- Compilation failed. Compile may still have updated the PCS, tho.
1211 CompErrs -> return Nothing
1213 -- Compilation "succeeded", and may or may not have returned a new
1214 -- linkable (depending on whether compilation was actually performed
1216 CompOK new_details new_iface new_linkable
1217 -> do let new_info = HomeModInfo { hm_iface = new_iface,
1218 hm_details = new_details,
1219 hm_linkable = new_linkable }
1220 return (Just new_info)
1223 -- Filter modules in the HPT
1224 retainInTopLevelEnvs :: [ModuleName] -> HomePackageTable -> HomePackageTable
1225 retainInTopLevelEnvs keep_these hpt
1226 = listToUFM [ (mod, expectJust "retain" mb_mod_info)
1228 , let mb_mod_info = lookupUFM hpt mod
1229 , isJust mb_mod_info ]
1231 -- ---------------------------------------------------------------------------
1232 -- Topological sort of the module graph
1235 :: Bool -- Drop hi-boot nodes? (see below)
1239 -- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1240 -- The resulting list of strongly-connected-components is in topologically
1241 -- sorted order, starting with the module(s) at the bottom of the
1242 -- dependency graph (ie compile them first) and ending with the ones at
1245 -- Drop hi-boot nodes (first boolean arg)?
1247 -- False: treat the hi-boot summaries as nodes of the graph,
1248 -- so the graph must be acyclic
1250 -- True: eliminate the hi-boot nodes, and instead pretend
1251 -- the a source-import of Foo is an import of Foo
1252 -- The resulting graph has no hi-boot nodes, but can by cyclic
1254 topSortModuleGraph drop_hs_boot_nodes summaries Nothing
1255 = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
1256 topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
1257 = stronglyConnComp (map vertex_fn (reachable graph root))
1259 -- restrict the graph to just those modules reachable from
1260 -- the specified module. We do this by building a graph with
1261 -- the full set of nodes, and determining the reachable set from
1262 -- the specified node.
1263 (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
1264 (graph, vertex_fn, key_fn) = graphFromEdges' nodes
1266 | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
1267 | otherwise = throwDyn (ProgramError "module does not exist")
1269 moduleGraphNodes :: Bool -> [ModSummary]
1270 -> ([(ModSummary, Int, [Int])], HscSource -> ModuleName -> Maybe Int)
1271 moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
1273 -- Drop hs-boot nodes by using HsSrcFile as the key
1274 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1275 | otherwise = HsBootFile
1277 -- We use integers as the keys for the SCC algorithm
1278 nodes :: [(ModSummary, Int, [Int])]
1279 nodes = [(s, expectJust "topSort" $
1280 lookup_key (ms_hsc_src s) (ms_mod_name s),
1281 out_edge_keys hs_boot_key (map unLoc (ms_srcimps s)) ++
1282 out_edge_keys HsSrcFile (map unLoc (ms_imps s)) ++
1283 (-- see [boot-edges] below
1284 if drop_hs_boot_nodes || ms_hsc_src s == HsBootFile
1286 else case lookup_key HsBootFile (ms_mod_name s) of
1291 , not (isBootSummary s && drop_hs_boot_nodes) ]
1292 -- Drop the hi-boot ones if told to do so
1294 -- [boot-edges] if this is a .hs and there is an equivalent
1295 -- .hs-boot, add a link from the former to the latter. This
1296 -- has the effect of detecting bogus cases where the .hs-boot
1297 -- depends on the .hs, by introducing a cycle. Additionally,
1298 -- it ensures that we will always process the .hs-boot before
1299 -- the .hs, and so the HomePackageTable will always have the
1300 -- most up to date information.
1302 key_map :: NodeMap Int
1303 key_map = listToFM ([(moduleName (ms_mod s), ms_hsc_src s)
1307 lookup_key :: HscSource -> ModuleName -> Maybe Int
1308 lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
1310 out_edge_keys :: HscSource -> [ModuleName] -> [Int]
1311 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1312 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1313 -- the IsBootInterface parameter True; else False
1316 type NodeKey = (ModuleName, HscSource) -- The nodes of the graph are
1317 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1319 msKey :: ModSummary -> NodeKey
1320 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (moduleName mod,boot)
1322 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1323 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1325 nodeMapElts :: NodeMap a -> [a]
1326 nodeMapElts = eltsFM
1328 -- If there are {-# SOURCE #-} imports between strongly connected
1329 -- components in the topological sort, then those imports can
1330 -- definitely be replaced by ordinary non-SOURCE imports: if SOURCE
1331 -- were necessary, then the edge would be part of a cycle.
1332 warnUnnecessarySourceImports :: DynFlags -> [SCC ModSummary] -> IO ()
1333 warnUnnecessarySourceImports dflags sccs =
1334 printBagOfWarnings dflags (listToBag (concat (map (check.flattenSCC) sccs)))
1336 let mods_in_this_cycle = map ms_mod_name ms in
1337 [ warn m i | m <- ms, i <- ms_srcimps m,
1338 unLoc i `notElem` mods_in_this_cycle ]
1340 warn :: ModSummary -> Located ModuleName -> WarnMsg
1341 warn ms (L loc mod) =
1343 (ptext SLIT("Warning: {-# SOURCE #-} unnecessary in import of ")
1344 <+> quotes (ppr mod))
1346 -----------------------------------------------------------------------------
1347 -- Downsweep (dependency analysis)
1349 -- Chase downwards from the specified root set, returning summaries
1350 -- for all home modules encountered. Only follow source-import
1353 -- We pass in the previous collection of summaries, which is used as a
1354 -- cache to avoid recalculating a module summary if the source is
1357 -- The returned list of [ModSummary] nodes has one node for each home-package
1358 -- module, plus one for any hs-boot files. The imports of these nodes
1359 -- are all there, including the imports of non-home-package modules.
1362 -> [ModSummary] -- Old summaries
1363 -> [ModuleName] -- Ignore dependencies on these; treat
1364 -- them as if they were package modules
1365 -> Bool -- True <=> allow multiple targets to have
1366 -- the same module name; this is
1367 -- very useful for ghc -M
1368 -> IO (Maybe [ModSummary])
1369 -- The elts of [ModSummary] all have distinct
1370 -- (Modules, IsBoot) identifiers, unless the Bool is true
1371 -- in which case there can be repeats
1372 downsweep hsc_env old_summaries excl_mods allow_dup_roots
1373 = -- catch error messages and return them
1374 handleDyn (\err_msg -> printBagOfErrors (hsc_dflags hsc_env) (unitBag err_msg) >> return Nothing) $ do
1375 rootSummaries <- mapM getRootSummary roots
1376 let root_map = mkRootMap rootSummaries
1377 checkDuplicates root_map
1378 summs <- loop (concatMap msDeps rootSummaries) root_map
1381 roots = hsc_targets hsc_env
1383 old_summary_map :: NodeMap ModSummary
1384 old_summary_map = mkNodeMap old_summaries
1386 getRootSummary :: Target -> IO ModSummary
1387 getRootSummary (Target (TargetFile file mb_phase) maybe_buf)
1388 = do exists <- doesFileExist file
1390 then summariseFile hsc_env old_summaries file mb_phase maybe_buf
1391 else throwDyn $ mkPlainErrMsg noSrcSpan $
1392 text "can't find file:" <+> text file
1393 getRootSummary (Target (TargetModule modl) maybe_buf)
1394 = do maybe_summary <- summariseModule hsc_env old_summary_map False
1395 (L rootLoc modl) maybe_buf excl_mods
1396 case maybe_summary of
1397 Nothing -> packageModErr modl
1400 rootLoc = mkGeneralSrcSpan FSLIT("<command line>")
1402 -- In a root module, the filename is allowed to diverge from the module
1403 -- name, so we have to check that there aren't multiple root files
1404 -- defining the same module (otherwise the duplicates will be silently
1405 -- ignored, leading to confusing behaviour).
1406 checkDuplicates :: NodeMap [ModSummary] -> IO ()
1407 checkDuplicates root_map
1408 | allow_dup_roots = return ()
1409 | null dup_roots = return ()
1410 | otherwise = multiRootsErr (head dup_roots)
1412 dup_roots :: [[ModSummary]] -- Each at least of length 2
1413 dup_roots = filterOut isSingleton (nodeMapElts root_map)
1415 loop :: [(Located ModuleName,IsBootInterface)]
1416 -- Work list: process these modules
1417 -> NodeMap [ModSummary]
1418 -- Visited set; the range is a list because
1419 -- the roots can have the same module names
1420 -- if allow_dup_roots is True
1422 -- The result includes the worklist, except
1423 -- for those mentioned in the visited set
1424 loop [] done = return (concat (nodeMapElts done))
1425 loop ((wanted_mod, is_boot) : ss) done
1426 | Just summs <- lookupFM done key
1427 = if isSingleton summs then
1430 do { multiRootsErr summs; return [] }
1431 | otherwise = do { mb_s <- summariseModule hsc_env old_summary_map
1432 is_boot wanted_mod Nothing excl_mods
1434 Nothing -> loop ss done
1435 Just s -> loop (msDeps s ++ ss)
1436 (addToFM done key [s]) }
1438 key = (unLoc wanted_mod, if is_boot then HsBootFile else HsSrcFile)
1440 mkRootMap :: [ModSummary] -> NodeMap [ModSummary]
1441 mkRootMap summaries = addListToFM_C (++) emptyFM
1442 [ (msKey s, [s]) | s <- summaries ]
1444 msDeps :: ModSummary -> [(Located ModuleName, IsBootInterface)]
1445 -- (msDeps s) returns the dependencies of the ModSummary s.
1446 -- A wrinkle is that for a {-# SOURCE #-} import we return
1447 -- *both* the hs-boot file
1448 -- *and* the source file
1449 -- as "dependencies". That ensures that the list of all relevant
1450 -- modules always contains B.hs if it contains B.hs-boot.
1451 -- Remember, this pass isn't doing the topological sort. It's
1452 -- just gathering the list of all relevant ModSummaries
1454 concat [ [(m,True), (m,False)] | m <- ms_srcimps s ]
1455 ++ [ (m,False) | m <- ms_imps s ]
1457 -----------------------------------------------------------------------------
1458 -- Summarising modules
1460 -- We have two types of summarisation:
1462 -- * Summarise a file. This is used for the root module(s) passed to
1463 -- cmLoadModules. The file is read, and used to determine the root
1464 -- module name. The module name may differ from the filename.
1466 -- * Summarise a module. We are given a module name, and must provide
1467 -- a summary. The finder is used to locate the file in which the module
1472 -> [ModSummary] -- old summaries
1473 -> FilePath -- source file name
1474 -> Maybe Phase -- start phase
1475 -> Maybe (StringBuffer,ClockTime)
1478 summariseFile hsc_env old_summaries file mb_phase maybe_buf
1479 -- we can use a cached summary if one is available and the
1480 -- source file hasn't changed, But we have to look up the summary
1481 -- by source file, rather than module name as we do in summarise.
1482 | Just old_summary <- findSummaryBySourceFile old_summaries file
1484 let location = ms_location old_summary
1486 -- return the cached summary if the source didn't change
1487 src_timestamp <- case maybe_buf of
1488 Just (_,t) -> return t
1489 Nothing -> getModificationTime file
1490 -- The file exists; we checked in getRootSummary above.
1491 -- If it gets removed subsequently, then this
1492 -- getModificationTime may fail, but that's the right
1495 if ms_hs_date old_summary == src_timestamp
1496 then do -- update the object-file timestamp
1497 obj_timestamp <- getObjTimestamp location False
1498 return old_summary{ ms_obj_date = obj_timestamp }
1506 let dflags = hsc_dflags hsc_env
1508 (dflags', hspp_fn, buf)
1509 <- preprocessFile dflags file mb_phase maybe_buf
1511 (srcimps,the_imps, L _ mod_name) <- getImports dflags' buf hspp_fn
1513 -- Make a ModLocation for this file
1514 location <- mkHomeModLocation dflags mod_name file
1516 -- Tell the Finder cache where it is, so that subsequent calls
1517 -- to findModule will find it, even if it's not on any search path
1518 mod <- addHomeModuleToFinder hsc_env mod_name location
1520 src_timestamp <- case maybe_buf of
1521 Just (_,t) -> return t
1522 Nothing -> getModificationTime file
1523 -- getMofificationTime may fail
1525 obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
1527 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
1528 ms_location = location,
1529 ms_hspp_file = hspp_fn,
1530 ms_hspp_opts = dflags',
1531 ms_hspp_buf = Just buf,
1532 ms_srcimps = srcimps, ms_imps = the_imps,
1533 ms_hs_date = src_timestamp,
1534 ms_obj_date = obj_timestamp })
1536 findSummaryBySourceFile :: [ModSummary] -> FilePath -> Maybe ModSummary
1537 findSummaryBySourceFile summaries file
1538 = case [ ms | ms <- summaries, HsSrcFile <- [ms_hsc_src ms],
1539 expectJust "findSummaryBySourceFile" (ml_hs_file (ms_location ms)) == file ] of
1543 -- Summarise a module, and pick up source and timestamp.
1546 -> NodeMap ModSummary -- Map of old summaries
1547 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
1548 -> Located ModuleName -- Imported module to be summarised
1549 -> Maybe (StringBuffer, ClockTime)
1550 -> [ModuleName] -- Modules to exclude
1551 -> IO (Maybe ModSummary) -- Its new summary
1553 summariseModule hsc_env old_summary_map is_boot (L loc wanted_mod) maybe_buf excl_mods
1554 | wanted_mod `elem` excl_mods
1557 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
1558 = do -- Find its new timestamp; all the
1559 -- ModSummaries in the old map have valid ml_hs_files
1560 let location = ms_location old_summary
1561 src_fn = expectJust "summariseModule" (ml_hs_file location)
1563 -- check the modification time on the source file, and
1564 -- return the cached summary if it hasn't changed. If the
1565 -- file has disappeared, we need to call the Finder again.
1567 Just (_,t) -> check_timestamp old_summary location src_fn t
1569 m <- System.IO.Error.try (getModificationTime src_fn)
1571 Right t -> check_timestamp old_summary location src_fn t
1572 Left e | isDoesNotExistError e -> find_it
1573 | otherwise -> ioError e
1575 | otherwise = find_it
1577 dflags = hsc_dflags hsc_env
1579 hsc_src = if is_boot then HsBootFile else HsSrcFile
1581 check_timestamp old_summary location src_fn src_timestamp
1582 | ms_hs_date old_summary == src_timestamp = do
1583 -- update the object-file timestamp
1584 obj_timestamp <- getObjTimestamp location is_boot
1585 return (Just old_summary{ ms_obj_date = obj_timestamp })
1587 -- source changed: re-summarise.
1588 new_summary location (ms_mod old_summary) src_fn src_timestamp
1591 -- Don't use the Finder's cache this time. If the module was
1592 -- previously a package module, it may have now appeared on the
1593 -- search path, so we want to consider it to be a home module. If
1594 -- the module was previously a home module, it may have moved.
1595 uncacheModule hsc_env wanted_mod
1596 found <- findImportedModule hsc_env wanted_mod Nothing
1599 | isJust (ml_hs_file location) ->
1601 just_found location mod
1603 -- Drop external-pkg
1604 ASSERT(modulePackageId mod /= thisPackage dflags)
1608 err -> noModError dflags loc wanted_mod err
1611 just_found location mod = do
1612 -- Adjust location to point to the hs-boot source file,
1613 -- hi file, object file, when is_boot says so
1614 let location' | is_boot = addBootSuffixLocn location
1615 | otherwise = location
1616 src_fn = expectJust "summarise2" (ml_hs_file location')
1618 -- Check that it exists
1619 -- It might have been deleted since the Finder last found it
1620 maybe_t <- modificationTimeIfExists src_fn
1622 Nothing -> noHsFileErr loc src_fn
1623 Just t -> new_summary location' mod src_fn t
1626 new_summary location mod src_fn src_timestamp
1628 -- Preprocess the source file and get its imports
1629 -- The dflags' contains the OPTIONS pragmas
1630 (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn Nothing maybe_buf
1631 (srcimps, the_imps, L mod_loc mod_name) <- getImports dflags' buf hspp_fn
1633 when (mod_name /= wanted_mod) $
1634 throwDyn $ mkPlainErrMsg mod_loc $
1635 text "file name does not match module name"
1636 <+> quotes (ppr mod_name)
1638 -- Find the object timestamp, and return the summary
1639 obj_timestamp <- getObjTimestamp location is_boot
1641 return (Just ( ModSummary { ms_mod = mod,
1642 ms_hsc_src = hsc_src,
1643 ms_location = location,
1644 ms_hspp_file = hspp_fn,
1645 ms_hspp_opts = dflags',
1646 ms_hspp_buf = Just buf,
1647 ms_srcimps = srcimps,
1649 ms_hs_date = src_timestamp,
1650 ms_obj_date = obj_timestamp }))
1653 getObjTimestamp location is_boot
1654 = if is_boot then return Nothing
1655 else modificationTimeIfExists (ml_obj_file location)
1658 preprocessFile :: DynFlags -> FilePath -> Maybe Phase -> Maybe (StringBuffer,ClockTime)
1659 -> IO (DynFlags, FilePath, StringBuffer)
1660 preprocessFile dflags src_fn mb_phase Nothing
1662 (dflags', hspp_fn) <- preprocess dflags (src_fn, mb_phase)
1663 buf <- hGetStringBuffer hspp_fn
1664 return (dflags', hspp_fn, buf)
1666 preprocessFile dflags src_fn mb_phase (Just (buf, time))
1668 -- case we bypass the preprocessing stage?
1670 local_opts = getOptions buf src_fn
1672 (dflags', errs) <- parseDynamicFlags dflags (map unLoc local_opts)
1676 | Just (Unlit _) <- mb_phase = True
1677 | Nothing <- mb_phase, Unlit _ <- startPhase src_fn = True
1678 -- note: local_opts is only required if there's no Unlit phase
1679 | dopt Opt_Cpp dflags' = True
1680 | dopt Opt_Pp dflags' = True
1683 when needs_preprocessing $
1684 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
1686 return (dflags', src_fn, buf)
1689 -----------------------------------------------------------------------------
1691 -----------------------------------------------------------------------------
1693 noModError :: DynFlags -> SrcSpan -> ModuleName -> FindResult -> IO ab
1694 -- ToDo: we don't have a proper line number for this error
1695 noModError dflags loc wanted_mod err
1696 = throwDyn $ mkPlainErrMsg loc $ cannotFindModule dflags wanted_mod err
1698 noHsFileErr loc path
1699 = throwDyn $ mkPlainErrMsg loc $ text "Can't find" <+> text path
1702 = throwDyn $ mkPlainErrMsg noSrcSpan $
1703 text "module" <+> quotes (ppr mod) <+> text "is a package module"
1705 multiRootsErr :: [ModSummary] -> IO ()
1706 multiRootsErr summs@(summ1:_)
1707 = throwDyn $ mkPlainErrMsg noSrcSpan $
1708 text "module" <+> quotes (ppr mod) <+>
1709 text "is defined in multiple files:" <+>
1710 sep (map text files)
1713 files = map (expectJust "checkDup" . ml_hs_file . ms_location) summs
1715 cyclicModuleErr :: [ModSummary] -> SDoc
1717 = hang (ptext SLIT("Module imports form a cycle for modules:"))
1718 2 (vcat (map show_one ms))
1720 show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
1721 nest 2 $ ptext SLIT("imports:") <+>
1722 (pp_imps HsBootFile (ms_srcimps ms)
1723 $$ pp_imps HsSrcFile (ms_imps ms))]
1724 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
1725 pp_imps src mods = fsep (map (show_mod src) mods)
1728 -- | Inform GHC that the working directory has changed. GHC will flush
1729 -- its cache of module locations, since it may no longer be valid.
1730 -- Note: if you change the working directory, you should also unload
1731 -- the current program (set targets to empty, followed by load).
1732 workingDirectoryChanged :: Session -> IO ()
1733 workingDirectoryChanged s = withSession s $ flushFinderCaches
1735 -- -----------------------------------------------------------------------------
1736 -- inspecting the session
1738 -- | Get the module dependency graph.
1739 getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
1740 getModuleGraph s = withSession s (return . hsc_mod_graph)
1742 isLoaded :: Session -> ModuleName -> IO Bool
1743 isLoaded s m = withSession s $ \hsc_env ->
1744 return $! isJust (lookupUFM (hsc_HPT hsc_env) m)
1746 getBindings :: Session -> IO [TyThing]
1747 getBindings s = withSession s $ \hsc_env ->
1748 -- we have to implement the shadowing behaviour of ic_tmp_ids here
1749 -- (see InteractiveContext) and the quickest way is to use an OccEnv.
1751 tmp_ids = reverse (ic_tmp_ids (hsc_IC hsc_env))
1752 env = mkOccEnv [ (nameOccName (idName id), id) | id <- tmp_ids ]
1754 return (map AnId (occEnvElts env))
1756 getPrintUnqual :: Session -> IO PrintUnqualified
1757 getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
1759 -- | Container for information about a 'Module'.
1760 data ModuleInfo = ModuleInfo {
1761 minf_type_env :: TypeEnv,
1762 minf_exports :: NameSet, -- ToDo, [AvailInfo] like ModDetails?
1763 minf_rdr_env :: Maybe GlobalRdrEnv, -- Nothing for a compiled/package mod
1764 minf_instances :: [Instance]
1766 ,minf_modBreaks :: ModBreaks
1768 -- ToDo: this should really contain the ModIface too
1770 -- We don't want HomeModInfo here, because a ModuleInfo applies
1771 -- to package modules too.
1773 -- | Request information about a loaded 'Module'
1774 getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
1775 getModuleInfo s mdl = withSession s $ \hsc_env -> do
1776 let mg = hsc_mod_graph hsc_env
1777 if mdl `elem` map ms_mod mg
1778 then getHomeModuleInfo hsc_env (moduleName mdl)
1780 {- if isHomeModule (hsc_dflags hsc_env) mdl
1782 else -} getPackageModuleInfo hsc_env mdl
1783 -- getPackageModuleInfo will attempt to find the interface, so
1784 -- we don't want to call it for a home module, just in case there
1785 -- was a problem loading the module and the interface doesn't
1786 -- exist... hence the isHomeModule test here. (ToDo: reinstate)
1788 getPackageModuleInfo :: HscEnv -> Module -> IO (Maybe ModuleInfo)
1789 getPackageModuleInfo hsc_env mdl = do
1791 (_msgs, mb_avails) <- getModuleExports hsc_env mdl
1793 Nothing -> return Nothing
1795 eps <- readIORef (hsc_EPS hsc_env)
1797 names = availsToNameSet avails
1799 tys = [ ty | name <- concatMap availNames avails,
1800 Just ty <- [lookupTypeEnv pte name] ]
1802 return (Just (ModuleInfo {
1803 minf_type_env = mkTypeEnv tys,
1804 minf_exports = names,
1805 minf_rdr_env = Just $! nameSetToGlobalRdrEnv names (moduleName mdl),
1806 minf_instances = error "getModuleInfo: instances for package module unimplemented",
1807 minf_modBreaks = emptyModBreaks
1810 -- bogusly different for non-GHCI (ToDo)
1814 getHomeModuleInfo hsc_env mdl =
1815 case lookupUFM (hsc_HPT hsc_env) mdl of
1816 Nothing -> return Nothing
1818 let details = hm_details hmi
1819 return (Just (ModuleInfo {
1820 minf_type_env = md_types details,
1821 minf_exports = availsToNameSet (md_exports details),
1822 minf_rdr_env = mi_globals $! hm_iface hmi,
1823 minf_instances = md_insts details
1825 ,minf_modBreaks = md_modBreaks details
1829 -- | The list of top-level entities defined in a module
1830 modInfoTyThings :: ModuleInfo -> [TyThing]
1831 modInfoTyThings minf = typeEnvElts (minf_type_env minf)
1833 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
1834 modInfoTopLevelScope minf
1835 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
1837 modInfoExports :: ModuleInfo -> [Name]
1838 modInfoExports minf = nameSetToList $! minf_exports minf
1840 -- | Returns the instances defined by the specified module.
1841 -- Warning: currently unimplemented for package modules.
1842 modInfoInstances :: ModuleInfo -> [Instance]
1843 modInfoInstances = minf_instances
1845 modInfoIsExportedName :: ModuleInfo -> Name -> Bool
1846 modInfoIsExportedName minf name = elemNameSet name (minf_exports minf)
1848 modInfoPrintUnqualified :: ModuleInfo -> Maybe PrintUnqualified
1849 modInfoPrintUnqualified minf = fmap mkPrintUnqualified (minf_rdr_env minf)
1851 modInfoLookupName :: Session -> ModuleInfo -> Name -> IO (Maybe TyThing)
1852 modInfoLookupName s minf name = withSession s $ \hsc_env -> do
1853 case lookupTypeEnv (minf_type_env minf) name of
1854 Just tyThing -> return (Just tyThing)
1856 eps <- readIORef (hsc_EPS hsc_env)
1857 return $! lookupType (hsc_dflags hsc_env)
1858 (hsc_HPT hsc_env) (eps_PTE eps) name
1861 modInfoModBreaks = minf_modBreaks
1864 isDictonaryId :: Id -> Bool
1866 = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
1868 -- | Looks up a global name: that is, any top-level name in any
1869 -- visible module. Unlike 'lookupName', lookupGlobalName does not use
1870 -- the interactive context, and therefore does not require a preceding
1872 lookupGlobalName :: Session -> Name -> IO (Maybe TyThing)
1873 lookupGlobalName s name = withSession s $ \hsc_env -> do
1874 eps <- readIORef (hsc_EPS hsc_env)
1875 return $! lookupType (hsc_dflags hsc_env)
1876 (hsc_HPT hsc_env) (eps_PTE eps) name
1878 -- -----------------------------------------------------------------------------
1879 -- Misc exported utils
1881 dataConType :: DataCon -> Type
1882 dataConType dc = idType (dataConWrapId dc)
1884 -- | print a 'NamedThing', adding parentheses if the name is an operator.
1885 pprParenSymName :: NamedThing a => a -> SDoc
1886 pprParenSymName a = parenSymOcc (getOccName a) (ppr (getName a))
1888 -- ----------------------------------------------------------------------------
1893 -- - Data and Typeable instances for HsSyn.
1895 -- ToDo: check for small transformations that happen to the syntax in
1896 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
1898 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
1899 -- to get from TyCons, Ids etc. to TH syntax (reify).
1901 -- :browse will use either lm_toplev or inspect lm_interface, depending
1902 -- on whether the module is interpreted or not.
1904 -- This is for reconstructing refactored source code
1905 -- Calls the lexer repeatedly.
1906 -- ToDo: add comment tokens to token stream
1907 getTokenStream :: Session -> Module -> IO [Located Token]
1910 -- -----------------------------------------------------------------------------
1911 -- Interactive evaluation
1913 -- | Takes a 'ModuleName' and possibly a 'PackageId', and consults the
1914 -- filesystem and package database to find the corresponding 'Module',
1915 -- using the algorithm that is used for an @import@ declaration.
1916 findModule :: Session -> ModuleName -> Maybe PackageId -> IO Module
1917 findModule s mod_name maybe_pkg = withSession s $ \hsc_env ->
1918 findModule' hsc_env mod_name maybe_pkg
1920 findModule' hsc_env mod_name maybe_pkg =
1922 dflags = hsc_dflags hsc_env
1923 hpt = hsc_HPT hsc_env
1924 this_pkg = thisPackage dflags
1926 case lookupUFM hpt mod_name of
1927 Just mod_info -> return (mi_module (hm_iface mod_info))
1928 _not_a_home_module -> do
1929 res <- findImportedModule hsc_env mod_name maybe_pkg
1931 Found _ m | modulePackageId m /= this_pkg -> return m
1932 | otherwise -> throwDyn (CmdLineError (showSDoc $
1933 text "module" <+> pprModule m <+>
1934 text "is not loaded"))
1935 err -> let msg = cannotFindModule dflags mod_name err in
1936 throwDyn (CmdLineError (showSDoc msg))