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), getHistorySpan,
91 InteractiveEval.forward,
94 compileExpr, HValue, dynCompileExpr,
96 obtainTerm, obtainTerm1,
98 ModBreaks(..), BreakIndex,
99 BreakInfo(breakInfo_number, breakInfo_module),
100 BreakArray, setBreakOn, setBreakOff, getBreak,
103 -- * Abstract syntax elements
109 Module, mkModule, pprModule, moduleName, modulePackageId,
110 ModuleName, mkModuleName, moduleNameString,
114 isExternalName, nameModule, pprParenSymName, nameSrcSpan,
116 RdrName(Qual,Unqual),
120 isImplicitId, isDeadBinder,
121 isExportedId, isLocalId, isGlobalId,
123 isPrimOpId, isFCallId, isClassOpId_maybe,
124 isDataConWorkId, idDataCon,
125 isBottomingId, isDictonaryId,
126 recordSelectorFieldLabel,
128 -- ** Type constructors
130 tyConTyVars, tyConDataCons, tyConArity,
131 isClassTyCon, isSynTyCon, isNewTyCon, isPrimTyCon, isFunTyCon,
133 synTyConDefn, synTyConType, synTyConResKind,
139 -- ** Data constructors
141 dataConSig, dataConType, dataConTyCon, dataConFieldLabels,
142 dataConIsInfix, isVanillaDataCon,
144 StrictnessMark(..), isMarkedStrict,
148 classMethods, classSCTheta, classTvsFds,
153 instanceDFunId, pprInstance, pprInstanceHdr,
155 -- ** Types and Kinds
156 Type, dropForAlls, splitForAllTys, funResultTy,
157 pprParendType, pprTypeApp,
160 ThetaType, pprThetaArrow,
166 module HsSyn, -- ToDo: remove extraneous bits
170 defaultFixity, maxPrecedence,
174 -- ** Source locations
176 mkSrcLoc, isGoodSrcLoc, noSrcLoc,
177 srcLocFile, srcLocLine, srcLocCol,
179 mkSrcSpan, srcLocSpan, isGoodSrcSpan, noSrcSpan,
180 srcSpanStart, srcSpanEnd,
182 srcSpanStartLine, srcSpanEndLine,
183 srcSpanStartCol, srcSpanEndCol,
186 GhcException(..), showGhcException,
196 * inline bits of HscMain here to simplify layering: hscTcExpr, hscStmt.
197 * what StaticFlags should we expose, if any?
200 #include "HsVersions.h"
203 import qualified Linker
204 import Linker ( HValue )
209 import InteractiveEval
216 import Type hiding (typeKind)
217 import TcType hiding (typeKind)
219 import Var hiding (setIdType)
220 import TysPrim ( alphaTyVars )
225 import Name hiding ( varName )
226 import OccName ( parenSymOcc )
227 import InstEnv ( Instance, instanceDFunId, pprInstance, pprInstanceHdr )
231 import TcRnDriver ( tcRnModule )
232 import DriverPipeline
233 import DriverPhases ( HscSource(..), Phase(..), isHaskellSrcFilename, startPhase )
234 import HeaderInfo ( getImports, getOptions )
236 import HscMain ( newHscEnv, hscFileCheck, HscChecked(..) )
240 import SysTools ( initSysTools, cleanTempFiles, cleanTempFilesExcept,
250 import Bag ( unitBag, listToBag )
251 import ErrUtils ( Severity(..), showPass, fatalErrorMsg, debugTraceMsg,
252 mkPlainErrMsg, printBagOfErrors, printBagOfWarnings,
254 import qualified ErrUtils
256 import StringBuffer ( StringBuffer, hGetStringBuffer )
259 import Maybes ( expectJust, mapCatMaybes )
261 import HaddockLex ( tokenise )
263 import Control.Concurrent
264 import System.Directory ( getModificationTime, doesFileExist )
267 import qualified Data.List as List
269 import System.Exit ( exitWith, ExitCode(..) )
270 import System.Time ( ClockTime )
271 import Control.Exception as Exception hiding (handle)
274 import System.IO.Error ( try, isDoesNotExistError )
275 import Prelude hiding (init)
278 -- -----------------------------------------------------------------------------
279 -- Exception handlers
281 -- | Install some default exception handlers and run the inner computation.
282 -- Unless you want to handle exceptions yourself, you should wrap this around
283 -- the top level of your program. The default handlers output the error
284 -- message(s) to stderr and exit cleanly.
285 defaultErrorHandler :: DynFlags -> IO a -> IO a
286 defaultErrorHandler dflags inner =
287 -- top-level exception handler: any unrecognised exception is a compiler bug.
288 handle (\exception -> do
291 -- an IO exception probably isn't our fault, so don't panic
293 fatalErrorMsg dflags (text (show exception))
294 AsyncException StackOverflow ->
295 fatalErrorMsg dflags (text "stack overflow: use +RTS -K<size> to increase it")
297 fatalErrorMsg dflags (text (show (Panic (show exception))))
298 exitWith (ExitFailure 1)
301 -- program errors: messages with locations attached. Sometimes it is
302 -- convenient to just throw these as exceptions.
303 handleDyn (\dyn -> do printBagOfErrors dflags (unitBag dyn)
304 exitWith (ExitFailure 1)) $
306 -- error messages propagated as exceptions
307 handleDyn (\dyn -> do
310 PhaseFailed _ code -> exitWith code
311 Interrupted -> exitWith (ExitFailure 1)
312 _ -> do fatalErrorMsg dflags (text (show (dyn :: GhcException)))
313 exitWith (ExitFailure 1)
317 -- | Install a default cleanup handler to remove temporary files
318 -- deposited by a GHC run. This is seperate from
319 -- 'defaultErrorHandler', because you might want to override the error
320 -- handling, but still get the ordinary cleanup behaviour.
321 defaultCleanupHandler :: DynFlags -> IO a -> IO a
322 defaultCleanupHandler dflags inner =
323 -- make sure we clean up after ourselves
324 later (do cleanTempFiles dflags
327 -- exceptions will be blocked while we clean the temporary files,
328 -- so there shouldn't be any difficulty if we receive further
333 -- | Starts a new session. A session consists of a set of loaded
334 -- modules, a set of options (DynFlags), and an interactive context.
335 newSession :: Maybe FilePath -> IO Session
336 newSession mb_top_dir = do
338 main_thread <- myThreadId
339 modifyMVar_ interruptTargetThread (return . (main_thread :))
340 installSignalHandlers
343 dflags0 <- initSysTools mb_top_dir defaultDynFlags
344 dflags <- initDynFlags dflags0
345 env <- newHscEnv dflags
349 -- tmp: this breaks the abstraction, but required because DriverMkDepend
350 -- needs to call the Finder. ToDo: untangle this.
351 sessionHscEnv :: Session -> IO HscEnv
352 sessionHscEnv (Session ref) = readIORef ref
354 -- -----------------------------------------------------------------------------
357 -- | Grabs the DynFlags from the Session
358 getSessionDynFlags :: Session -> IO DynFlags
359 getSessionDynFlags s = withSession s (return . hsc_dflags)
361 -- | Updates the DynFlags in a Session. This also reads
362 -- the package database (unless it has already been read),
363 -- and prepares the compilers knowledge about packages. It
364 -- can be called again to load new packages: just add new
365 -- package flags to (packageFlags dflags).
367 -- Returns a list of new packages that may need to be linked in using
368 -- the dynamic linker (see 'linkPackages') as a result of new package
369 -- flags. If you are not doing linking or doing static linking, you
370 -- can ignore the list of packages returned.
372 setSessionDynFlags :: Session -> DynFlags -> IO [PackageId]
373 setSessionDynFlags (Session ref) dflags = do
374 hsc_env <- readIORef ref
375 (dflags', preload) <- initPackages dflags
376 writeIORef ref $! hsc_env{ hsc_dflags = dflags' }
379 -- | If there is no -o option, guess the name of target executable
380 -- by using top-level source file name as a base.
381 guessOutputFile :: Session -> IO ()
382 guessOutputFile s = modifySession s $ \env ->
383 let dflags = hsc_dflags env
384 mod_graph = hsc_mod_graph env
385 mainModuleSrcPath, guessedName :: Maybe String
386 mainModuleSrcPath = do
387 let isMain = (== mainModIs dflags) . ms_mod
388 [ms] <- return (filter isMain mod_graph)
389 ml_hs_file (ms_location ms)
390 guessedName = fmap basenameOf mainModuleSrcPath
392 case outputFile dflags of
394 Nothing -> env { hsc_dflags = dflags { outputFile = guessedName } }
396 -- -----------------------------------------------------------------------------
399 -- ToDo: think about relative vs. absolute file paths. And what
400 -- happens when the current directory changes.
402 -- | Sets the targets for this session. Each target may be a module name
403 -- or a filename. The targets correspond to the set of root modules for
404 -- the program\/library. Unloading the current program is achieved by
405 -- setting the current set of targets to be empty, followed by load.
406 setTargets :: Session -> [Target] -> IO ()
407 setTargets s targets = modifySession s (\h -> h{ hsc_targets = targets })
409 -- | returns the current set of targets
410 getTargets :: Session -> IO [Target]
411 getTargets s = withSession s (return . hsc_targets)
413 -- | Add another target
414 addTarget :: Session -> Target -> IO ()
416 = modifySession s (\h -> h{ hsc_targets = target : hsc_targets h })
419 removeTarget :: Session -> TargetId -> IO ()
420 removeTarget s target_id
421 = modifySession s (\h -> h{ hsc_targets = filter (hsc_targets h) })
423 filter targets = [ t | t@(Target id _) <- targets, id /= target_id ]
425 -- Attempts to guess what Target a string refers to. This function implements
426 -- the --make/GHCi command-line syntax for filenames:
428 -- - if the string looks like a Haskell source filename, then interpret
430 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
432 -- - otherwise interpret the string as a module name
434 guessTarget :: String -> Maybe Phase -> IO Target
435 guessTarget file (Just phase)
436 = return (Target (TargetFile file (Just phase)) Nothing)
437 guessTarget file Nothing
438 | isHaskellSrcFilename file
439 = return (Target (TargetFile file Nothing) Nothing)
441 = do exists <- doesFileExist hs_file
443 then return (Target (TargetFile hs_file Nothing) Nothing)
445 exists <- doesFileExist lhs_file
447 then return (Target (TargetFile lhs_file Nothing) Nothing)
449 return (Target (TargetModule (mkModuleName file)) Nothing)
451 hs_file = file `joinFileExt` "hs"
452 lhs_file = file `joinFileExt` "lhs"
454 -- -----------------------------------------------------------------------------
455 -- Extending the program scope
457 extendGlobalRdrScope :: Session -> [GlobalRdrElt] -> IO ()
458 extendGlobalRdrScope session rdrElts
459 = modifySession session $ \hscEnv ->
460 let global_rdr = hsc_global_rdr_env hscEnv
461 in hscEnv{ hsc_global_rdr_env = foldl extendGlobalRdrEnv global_rdr rdrElts }
463 setGlobalRdrScope :: Session -> [GlobalRdrElt] -> IO ()
464 setGlobalRdrScope session rdrElts
465 = modifySession session $ \hscEnv ->
466 hscEnv{ hsc_global_rdr_env = foldl extendGlobalRdrEnv emptyGlobalRdrEnv rdrElts }
468 extendGlobalTypeScope :: Session -> [Id] -> IO ()
469 extendGlobalTypeScope session ids
470 = modifySession session $ \hscEnv ->
471 let global_type = hsc_global_type_env hscEnv
472 in hscEnv{ hsc_global_type_env = extendTypeEnvWithIds global_type ids }
474 setGlobalTypeScope :: Session -> [Id] -> IO ()
475 setGlobalTypeScope session ids
476 = modifySession session $ \hscEnv ->
477 hscEnv{ hsc_global_type_env = extendTypeEnvWithIds emptyTypeEnv ids }
479 -- -----------------------------------------------------------------------------
480 -- Parsing Haddock comments
482 parseHaddockComment :: String -> Either String (HsDoc RdrName)
483 parseHaddockComment string = parseHaddockParagraphs (tokenise string)
485 -- -----------------------------------------------------------------------------
486 -- Loading the program
488 -- Perform a dependency analysis starting from the current targets
489 -- and update the session with the new module graph.
490 depanal :: Session -> [ModuleName] -> Bool -> IO (Maybe ModuleGraph)
491 depanal (Session ref) excluded_mods allow_dup_roots = do
492 hsc_env <- readIORef ref
494 dflags = hsc_dflags hsc_env
495 targets = hsc_targets hsc_env
496 old_graph = hsc_mod_graph hsc_env
498 showPass dflags "Chasing dependencies"
499 debugTraceMsg dflags 2 (hcat [
500 text "Chasing modules from: ",
501 hcat (punctuate comma (map pprTarget targets))])
503 r <- downsweep hsc_env old_graph excluded_mods allow_dup_roots
505 Just mod_graph -> writeIORef ref hsc_env{ hsc_mod_graph = mod_graph }
510 -- | The result of load.
512 = LoadOk Errors -- ^ all specified targets were loaded successfully.
513 | LoadFailed Errors -- ^ not all modules were loaded.
515 type Errors = [String]
517 data ErrMsg = ErrMsg {
518 errMsgSeverity :: Severity, -- warning, error, etc.
519 errMsgSpans :: [SrcSpan],
520 errMsgShortDoc :: Doc,
521 errMsgExtraInfo :: Doc
527 | LoadUpTo ModuleName
528 | LoadDependenciesOf ModuleName
530 -- | Try to load the program. If a Module is supplied, then just
531 -- attempt to load up to this target. If no Module is supplied,
532 -- then try to load all targets.
533 load :: Session -> LoadHowMuch -> IO SuccessFlag
534 load s@(Session ref) how_much
536 -- Dependency analysis first. Note that this fixes the module graph:
537 -- even if we don't get a fully successful upsweep, the full module
538 -- graph is still retained in the Session. We can tell which modules
539 -- were successfully loaded by inspecting the Session's HPT.
540 mb_graph <- depanal s [] False
542 Just mod_graph -> load2 s how_much mod_graph
543 Nothing -> return Failed
545 load2 s@(Session ref) how_much mod_graph = do
547 hsc_env <- readIORef ref
549 let hpt1 = hsc_HPT hsc_env
550 let dflags = hsc_dflags hsc_env
552 -- The "bad" boot modules are the ones for which we have
553 -- B.hs-boot in the module graph, but no B.hs
554 -- The downsweep should have ensured this does not happen
556 let all_home_mods = [ms_mod_name s
557 | s <- mod_graph, not (isBootSummary s)]
559 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
560 not (ms_mod_name s `elem` all_home_mods)]
562 ASSERT( null bad_boot_mods ) return ()
564 -- mg2_with_srcimps drops the hi-boot nodes, returning a
565 -- graph with cycles. Among other things, it is used for
566 -- backing out partially complete cycles following a failed
567 -- upsweep, and for removing from hpt all the modules
568 -- not in strict downwards closure, during calls to compile.
569 let mg2_with_srcimps :: [SCC ModSummary]
570 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
572 -- If we can determine that any of the {-# SOURCE #-} imports
573 -- are definitely unnecessary, then emit a warning.
574 warnUnnecessarySourceImports dflags mg2_with_srcimps
577 -- check the stability property for each module.
578 stable_mods@(stable_obj,stable_bco)
579 = checkStability hpt1 mg2_with_srcimps all_home_mods
581 -- prune bits of the HPT which are definitely redundant now,
583 pruned_hpt = pruneHomePackageTable hpt1
584 (flattenSCCs mg2_with_srcimps)
589 debugTraceMsg dflags 2 (text "Stable obj:" <+> ppr stable_obj $$
590 text "Stable BCO:" <+> ppr stable_bco)
592 -- Unload any modules which are going to be re-linked this time around.
593 let stable_linkables = [ linkable
594 | m <- stable_obj++stable_bco,
595 Just hmi <- [lookupUFM pruned_hpt m],
596 Just linkable <- [hm_linkable hmi] ]
597 unload hsc_env stable_linkables
599 -- We could at this point detect cycles which aren't broken by
600 -- a source-import, and complain immediately, but it seems better
601 -- to let upsweep_mods do this, so at least some useful work gets
602 -- done before the upsweep is abandoned.
603 --hPutStrLn stderr "after tsort:\n"
604 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
606 -- Now do the upsweep, calling compile for each module in
607 -- turn. Final result is version 3 of everything.
609 -- Topologically sort the module graph, this time including hi-boot
610 -- nodes, and possibly just including the portion of the graph
611 -- reachable from the module specified in the 2nd argument to load.
612 -- This graph should be cycle-free.
613 -- If we're restricting the upsweep to a portion of the graph, we
614 -- also want to retain everything that is still stable.
615 let full_mg :: [SCC ModSummary]
616 full_mg = topSortModuleGraph False mod_graph Nothing
618 maybe_top_mod = case how_much of
620 LoadDependenciesOf m -> Just m
623 partial_mg0 :: [SCC ModSummary]
624 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
626 -- LoadDependenciesOf m: we want the upsweep to stop just
627 -- short of the specified module (unless the specified module
630 | LoadDependenciesOf mod <- how_much
631 = ASSERT( case last partial_mg0 of
632 AcyclicSCC ms -> ms_mod_name ms == mod; _ -> False )
633 List.init partial_mg0
639 | AcyclicSCC ms <- full_mg,
640 ms_mod_name ms `elem` stable_obj++stable_bco,
641 ms_mod_name ms `notElem` [ ms_mod_name ms' |
642 AcyclicSCC ms' <- partial_mg ] ]
644 mg = stable_mg ++ partial_mg
646 -- clean up between compilations
647 let cleanup = cleanTempFilesExcept dflags
648 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
650 debugTraceMsg dflags 2 (hang (text "Ready for upsweep")
652 (upsweep_ok, hsc_env1, modsUpswept)
653 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
654 pruned_hpt stable_mods cleanup mg
656 -- Make modsDone be the summaries for each home module now
657 -- available; this should equal the domain of hpt3.
658 -- Get in in a roughly top .. bottom order (hence reverse).
660 let modsDone = reverse modsUpswept
662 -- Try and do linking in some form, depending on whether the
663 -- upsweep was completely or only partially successful.
665 if succeeded upsweep_ok
668 -- Easy; just relink it all.
669 do debugTraceMsg dflags 2 (text "Upsweep completely successful.")
671 -- Clean up after ourselves
672 cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
674 -- Issue a warning for the confusing case where the user
675 -- said '-o foo' but we're not going to do any linking.
676 -- We attempt linking if either (a) one of the modules is
677 -- called Main, or (b) the user said -no-hs-main, indicating
678 -- that main() is going to come from somewhere else.
680 let ofile = outputFile dflags
681 let no_hs_main = dopt Opt_NoHsMain dflags
683 main_mod = mainModIs dflags
684 a_root_is_Main = any ((==main_mod).ms_mod) mod_graph
685 do_linking = a_root_is_Main || no_hs_main
687 when (ghcLink dflags == LinkBinary
688 && isJust ofile && not do_linking) $
689 debugTraceMsg dflags 1 $
690 text ("Warning: output was redirected with -o, " ++
691 "but no output will be generated\n" ++
692 "because there is no " ++
693 moduleNameString (moduleName main_mod) ++ " module.")
695 -- link everything together
696 linkresult <- link (ghcLink dflags) dflags do_linking (hsc_HPT hsc_env1)
698 loadFinish Succeeded linkresult ref hsc_env1
701 -- Tricky. We need to back out the effects of compiling any
702 -- half-done cycles, both so as to clean up the top level envs
703 -- and to avoid telling the interactive linker to link them.
704 do debugTraceMsg dflags 2 (text "Upsweep partially successful.")
707 = map ms_mod modsDone
708 let mods_to_zap_names
709 = findPartiallyCompletedCycles modsDone_names
712 = filter ((`notElem` mods_to_zap_names).ms_mod)
715 let hpt4 = retainInTopLevelEnvs (map ms_mod_name mods_to_keep)
718 -- Clean up after ourselves
719 cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
721 -- there should be no Nothings where linkables should be, now
722 ASSERT(all (isJust.hm_linkable)
723 (eltsUFM (hsc_HPT hsc_env))) do
725 -- Link everything together
726 linkresult <- link (ghcLink dflags) dflags False hpt4
728 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
729 loadFinish Failed linkresult ref hsc_env4
731 -- Finish up after a load.
733 -- If the link failed, unload everything and return.
734 loadFinish all_ok Failed ref hsc_env
735 = do unload hsc_env []
736 writeIORef ref $! discardProg hsc_env
739 -- Empty the interactive context and set the module context to the topmost
740 -- newly loaded module, or the Prelude if none were loaded.
741 loadFinish all_ok Succeeded ref hsc_env
742 = do writeIORef ref $! hsc_env{ hsc_IC = emptyInteractiveContext }
746 -- Forget the current program, but retain the persistent info in HscEnv
747 discardProg :: HscEnv -> HscEnv
749 = hsc_env { hsc_mod_graph = emptyMG,
750 hsc_IC = emptyInteractiveContext,
751 hsc_HPT = emptyHomePackageTable }
753 -- used to fish out the preprocess output files for the purposes of
754 -- cleaning up. The preprocessed file *might* be the same as the
755 -- source file, but that doesn't do any harm.
756 ppFilesFromSummaries summaries = map ms_hspp_file summaries
758 -- -----------------------------------------------------------------------------
762 CheckedModule { parsedSource :: ParsedSource,
763 renamedSource :: Maybe RenamedSource,
764 typecheckedSource :: Maybe TypecheckedSource,
765 checkedModuleInfo :: Maybe ModuleInfo
767 -- ToDo: improvements that could be made here:
768 -- if the module succeeded renaming but not typechecking,
769 -- we can still get back the GlobalRdrEnv and exports, so
770 -- perhaps the ModuleInfo should be split up into separate
771 -- fields within CheckedModule.
773 type ParsedSource = Located (HsModule RdrName)
774 type RenamedSource = (HsGroup Name, [LImportDecl Name], Maybe [LIE Name],
775 Maybe (HsDoc Name), HaddockModInfo Name)
776 type TypecheckedSource = LHsBinds Id
779 -- - things that aren't in the output of the typechecker right now:
783 -- - type/data/newtype declarations
784 -- - class declarations
786 -- - extra things in the typechecker's output:
787 -- - default methods are turned into top-level decls.
788 -- - dictionary bindings
791 -- | This is the way to get access to parsed and typechecked source code
792 -- for a module. 'checkModule' loads all the dependencies of the specified
793 -- module in the Session, and then attempts to typecheck the module. If
794 -- successful, it returns the abstract syntax for the module.
795 checkModule :: Session -> ModuleName -> IO (Maybe CheckedModule)
796 checkModule session@(Session ref) mod = do
797 -- load up the dependencies first
798 r <- load session (LoadDependenciesOf mod)
799 if (failed r) then return Nothing else do
801 -- now parse & typecheck the module
802 hsc_env <- readIORef ref
803 let mg = hsc_mod_graph hsc_env
804 case [ ms | ms <- mg, ms_mod_name ms == mod ] of
807 mbChecked <- hscFileCheck hsc_env{hsc_dflags=ms_hspp_opts ms} ms
809 Nothing -> return Nothing
810 Just (HscChecked parsed renamed Nothing) ->
811 return (Just (CheckedModule {
812 parsedSource = parsed,
813 renamedSource = renamed,
814 typecheckedSource = Nothing,
815 checkedModuleInfo = Nothing }))
816 Just (HscChecked parsed renamed
817 (Just (tc_binds, rdr_env, details))) -> do
818 let minf = ModuleInfo {
819 minf_type_env = md_types details,
820 minf_exports = availsToNameSet $
822 minf_rdr_env = Just rdr_env,
823 minf_instances = md_insts details
825 ,minf_modBreaks = emptyModBreaks
828 return (Just (CheckedModule {
829 parsedSource = parsed,
830 renamedSource = renamed,
831 typecheckedSource = Just tc_binds,
832 checkedModuleInfo = Just minf }))
834 -- | This is the way to get access to the Core bindings corresponding
835 -- to a module. 'compileToCore' first invokes 'checkModule' to parse and
836 -- typecheck the module, then desugars it and returns the resulting list
837 -- of Core bindings if successful. It is assumed that the given filename
838 -- has already been loaded.
839 compileToCore :: Session -> FilePath -> IO (Maybe [CoreBind])
840 compileToCore session@(Session ref) fn = do
841 hsc_env <- readIORef ref
842 -- First, determine the module name.
843 modSummary <- summariseFile hsc_env [] fn Nothing Nothing
844 let mod = moduleName $ ms_mod modSummary
845 -- Next, parse and typecheck the module
846 maybeCheckedModule <- checkModule session mod
847 case maybeCheckedModule of
848 Nothing -> return Nothing
849 Just checkedMod -> do
850 let parsedMod = parsedSource checkedMod
851 -- Note: this typechecks the module twice (because checkModule
852 -- also calls tcRnModule), but arranging for checkModule to
853 -- return the type env would require changing a lot of data
854 -- structures, so I'm leaving it like that for now.
855 (_, maybe_tc_result) <- tcRnModule hsc_env HsSrcFile False parsedMod
856 -- Get the type environment from the typechecking result
857 case maybe_tc_result of
858 -- TODO: this ignores the type error messages and just returns Nothing
859 Nothing -> return Nothing
861 let dflags = hsc_dflags hsc_env
862 -- Finally, compile to Core and return the resulting bindings
863 maybeModGuts <- deSugar hsc_env (ms_location modSummary) tcgEnv
865 Nothing -> return Nothing
866 Just mg -> return $ Just $ mg_binds mg
867 -- ---------------------------------------------------------------------------
870 unload :: HscEnv -> [Linkable] -> IO ()
871 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
872 = case ghcLink (hsc_dflags hsc_env) of
874 LinkInMemory -> Linker.unload (hsc_dflags hsc_env) stable_linkables
876 LinkInMemory -> panic "unload: no interpreter"
880 -- -----------------------------------------------------------------------------
884 Stability tells us which modules definitely do not need to be recompiled.
885 There are two main reasons for having stability:
887 - avoid doing a complete upsweep of the module graph in GHCi when
888 modules near the bottom of the tree have not changed.
890 - to tell GHCi when it can load object code: we can only load object code
891 for a module when we also load object code fo all of the imports of the
892 module. So we need to know that we will definitely not be recompiling
893 any of these modules, and we can use the object code.
895 The stability check is as follows. Both stableObject and
896 stableBCO are used during the upsweep phase later.
899 stable m = stableObject m || stableBCO m
902 all stableObject (imports m)
903 && old linkable does not exist, or is == on-disk .o
904 && date(on-disk .o) > date(.hs)
907 all stable (imports m)
908 && date(BCO) > date(.hs)
911 These properties embody the following ideas:
913 - if a module is stable, then:
914 - if it has been compiled in a previous pass (present in HPT)
915 then it does not need to be compiled or re-linked.
916 - if it has not been compiled in a previous pass,
917 then we only need to read its .hi file from disk and
918 link it to produce a ModDetails.
920 - if a modules is not stable, we will definitely be at least
921 re-linking, and possibly re-compiling it during the upsweep.
922 All non-stable modules can (and should) therefore be unlinked
925 - Note that objects are only considered stable if they only depend
926 on other objects. We can't link object code against byte code.
930 :: HomePackageTable -- HPT from last compilation
931 -> [SCC ModSummary] -- current module graph (cyclic)
932 -> [ModuleName] -- all home modules
933 -> ([ModuleName], -- stableObject
934 [ModuleName]) -- stableBCO
936 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
938 checkSCC (stable_obj, stable_bco) scc0
939 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
940 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
941 | otherwise = (stable_obj, stable_bco)
943 scc = flattenSCC scc0
944 scc_mods = map ms_mod_name scc
945 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
947 scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
948 -- all imports outside the current SCC, but in the home pkg
950 stable_obj_imps = map (`elem` stable_obj) scc_allimps
951 stable_bco_imps = map (`elem` stable_bco) scc_allimps
958 and (zipWith (||) stable_obj_imps stable_bco_imps)
962 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
966 same_as_prev t = case lookupUFM hpt (ms_mod_name ms) of
967 Just hmi | Just l <- hm_linkable hmi
968 -> isObjectLinkable l && t == linkableTime l
970 -- why '>=' rather than '>' above? If the filesystem stores
971 -- times to the nearset second, we may occasionally find that
972 -- the object & source have the same modification time,
973 -- especially if the source was automatically generated
974 -- and compiled. Using >= is slightly unsafe, but it matches
978 = case lookupUFM hpt (ms_mod_name ms) of
979 Just hmi | Just l <- hm_linkable hmi ->
980 not (isObjectLinkable l) &&
981 linkableTime l >= ms_hs_date ms
984 ms_allimps :: ModSummary -> [ModuleName]
985 ms_allimps ms = map unLoc (ms_srcimps ms ++ ms_imps ms)
987 -- -----------------------------------------------------------------------------
988 -- Prune the HomePackageTable
990 -- Before doing an upsweep, we can throw away:
992 -- - For non-stable modules:
993 -- - all ModDetails, all linked code
994 -- - all unlinked code that is out of date with respect to
997 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
998 -- space at the end of the upsweep, because the topmost ModDetails of the
999 -- old HPT holds on to the entire type environment from the previous
1002 pruneHomePackageTable
1005 -> ([ModuleName],[ModuleName])
1008 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
1011 | is_stable modl = hmi'
1012 | otherwise = hmi'{ hm_details = emptyModDetails }
1014 modl = moduleName (mi_module (hm_iface hmi))
1015 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
1016 = hmi{ hm_linkable = Nothing }
1019 where ms = expectJust "prune" (lookupUFM ms_map modl)
1021 ms_map = listToUFM [(ms_mod_name ms, ms) | ms <- summ]
1023 is_stable m = m `elem` stable_obj || m `elem` stable_bco
1025 -- -----------------------------------------------------------------------------
1027 -- Return (names of) all those in modsDone who are part of a cycle
1028 -- as defined by theGraph.
1029 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
1030 findPartiallyCompletedCycles modsDone theGraph
1034 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
1035 chew ((CyclicSCC vs):rest)
1036 = let names_in_this_cycle = nub (map ms_mod vs)
1038 = nub ([done | done <- modsDone,
1039 done `elem` names_in_this_cycle])
1040 chewed_rest = chew rest
1042 if notNull mods_in_this_cycle
1043 && length mods_in_this_cycle < length names_in_this_cycle
1044 then mods_in_this_cycle ++ chewed_rest
1047 -- -----------------------------------------------------------------------------
1050 -- This is where we compile each module in the module graph, in a pass
1051 -- from the bottom to the top of the graph.
1053 -- There better had not be any cyclic groups here -- we check for them.
1056 :: HscEnv -- Includes initially-empty HPT
1057 -> HomePackageTable -- HPT from last time round (pruned)
1058 -> ([ModuleName],[ModuleName]) -- stable modules (see checkStability)
1059 -> IO () -- How to clean up unwanted tmp files
1060 -> [SCC ModSummary] -- Mods to do (the worklist)
1062 HscEnv, -- With an updated HPT
1063 [ModSummary]) -- Mods which succeeded
1065 upsweep hsc_env old_hpt stable_mods cleanup mods
1066 = upsweep' hsc_env old_hpt stable_mods cleanup mods 1 (length mods)
1068 upsweep' hsc_env old_hpt stable_mods cleanup
1070 = return (Succeeded, hsc_env, [])
1072 upsweep' hsc_env old_hpt stable_mods cleanup
1073 (CyclicSCC ms:_) _ _
1074 = do fatalErrorMsg (hsc_dflags hsc_env) (cyclicModuleErr ms)
1075 return (Failed, hsc_env, [])
1077 upsweep' hsc_env old_hpt stable_mods cleanup
1078 (AcyclicSCC mod:mods) mod_index nmods
1079 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
1080 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
1081 -- (moduleEnvElts (hsc_HPT hsc_env)))
1083 mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods mod
1086 cleanup -- Remove unwanted tmp files between compilations
1089 Nothing -> return (Failed, hsc_env, [])
1091 { let this_mod = ms_mod_name mod
1093 -- Add new info to hsc_env
1094 hpt1 = addToUFM (hsc_HPT hsc_env) this_mod mod_info
1095 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
1097 -- Space-saving: delete the old HPT entry
1098 -- for mod BUT if mod is a hs-boot
1099 -- node, don't delete it. For the
1100 -- interface, the HPT entry is probaby for the
1101 -- main Haskell source file. Deleting it
1102 -- would force .. (what?? --SDM)
1103 old_hpt1 | isBootSummary mod = old_hpt
1104 | otherwise = delFromUFM old_hpt this_mod
1106 ; (restOK, hsc_env2, modOKs)
1107 <- upsweep' hsc_env1 old_hpt1 stable_mods cleanup
1108 mods (mod_index+1) nmods
1109 ; return (restOK, hsc_env2, mod:modOKs)
1113 -- Compile a single module. Always produce a Linkable for it if
1114 -- successful. If no compilation happened, return the old Linkable.
1115 upsweep_mod :: HscEnv
1117 -> ([ModuleName],[ModuleName])
1119 -> Int -- index of module
1120 -> Int -- total number of modules
1121 -> IO (Maybe HomeModInfo) -- Nothing => Failed
1123 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) summary mod_index nmods
1125 this_mod_name = ms_mod_name summary
1126 this_mod = ms_mod summary
1127 mb_obj_date = ms_obj_date summary
1128 obj_fn = ml_obj_file (ms_location summary)
1129 hs_date = ms_hs_date summary
1131 is_stable_obj = this_mod_name `elem` stable_obj
1132 is_stable_bco = this_mod_name `elem` stable_bco
1134 old_hmi = lookupUFM old_hpt this_mod_name
1136 -- We're using the dflags for this module now, obtained by
1137 -- applying any options in its LANGUAGE & OPTIONS_GHC pragmas.
1138 dflags = ms_hspp_opts summary
1139 prevailing_target = hscTarget (hsc_dflags hsc_env)
1140 local_target = hscTarget dflags
1142 -- If OPTIONS_GHC contains -fasm or -fvia-C, be careful that
1143 -- we don't do anything dodgy: these should only work to change
1144 -- from -fvia-C to -fasm and vice-versa, otherwise we could
1145 -- end up trying to link object code to byte code.
1146 target = if prevailing_target /= local_target
1147 && (not (isObjectTarget prevailing_target)
1148 || not (isObjectTarget local_target))
1149 then prevailing_target
1152 -- store the corrected hscTarget into the summary
1153 summary' = summary{ ms_hspp_opts = dflags { hscTarget = target } }
1155 -- The old interface is ok if
1156 -- a) we're compiling a source file, and the old HPT
1157 -- entry is for a source file
1158 -- b) we're compiling a hs-boot file
1159 -- Case (b) allows an hs-boot file to get the interface of its
1160 -- real source file on the second iteration of the compilation
1161 -- manager, but that does no harm. Otherwise the hs-boot file
1162 -- will always be recompiled
1167 Just hm_info | isBootSummary summary -> Just iface
1168 | not (mi_boot iface) -> Just iface
1169 | otherwise -> Nothing
1171 iface = hm_iface hm_info
1173 compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
1174 compile_it = upsweep_compile hsc_env old_hpt this_mod_name
1175 summary' mod_index nmods mb_old_iface
1177 compile_it_discard_iface
1178 = upsweep_compile hsc_env old_hpt this_mod_name
1179 summary' mod_index nmods Nothing
1185 -- Regardless of whether we're generating object code or
1186 -- byte code, we can always use an existing object file
1187 -- if it is *stable* (see checkStability).
1188 | is_stable_obj, isJust old_hmi ->
1190 -- object is stable, and we have an entry in the
1191 -- old HPT: nothing to do
1193 | is_stable_obj, isNothing old_hmi -> do
1194 linkable <- findObjectLinkable this_mod obj_fn
1195 (expectJust "upseep1" mb_obj_date)
1196 compile_it (Just linkable)
1197 -- object is stable, but we need to load the interface
1198 -- off disk to make a HMI.
1202 ASSERT(isJust old_hmi) -- must be in the old_hpt
1204 -- BCO is stable: nothing to do
1206 | Just hmi <- old_hmi,
1207 Just l <- hm_linkable hmi, not (isObjectLinkable l),
1208 linkableTime l >= ms_hs_date summary ->
1210 -- we have an old BCO that is up to date with respect
1211 -- to the source: do a recompilation check as normal.
1215 -- no existing code at all: we must recompile.
1217 -- When generating object code, if there's an up-to-date
1218 -- object file on the disk, then we can use it.
1219 -- However, if the object file is new (compared to any
1220 -- linkable we had from a previous compilation), then we
1221 -- must discard any in-memory interface, because this
1222 -- means the user has compiled the source file
1223 -- separately and generated a new interface, that we must
1224 -- read from the disk.
1226 obj | isObjectTarget obj,
1227 Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
1230 | Just l <- hm_linkable hmi,
1231 isObjectLinkable l && linkableTime l == obj_date
1232 -> compile_it (Just l)
1234 linkable <- findObjectLinkable this_mod obj_fn obj_date
1235 compile_it_discard_iface (Just linkable)
1241 -- Run hsc to compile a module
1242 upsweep_compile hsc_env old_hpt this_mod summary
1247 compresult <- compile hsc_env summary mb_old_linkable mb_old_iface
1251 -- Compilation failed. Compile may still have updated the PCS, tho.
1252 CompErrs -> return Nothing
1254 -- Compilation "succeeded", and may or may not have returned a new
1255 -- linkable (depending on whether compilation was actually performed
1257 CompOK new_details new_iface new_linkable
1258 -> do let new_info = HomeModInfo { hm_iface = new_iface,
1259 hm_details = new_details,
1260 hm_linkable = new_linkable }
1261 return (Just new_info)
1264 -- Filter modules in the HPT
1265 retainInTopLevelEnvs :: [ModuleName] -> HomePackageTable -> HomePackageTable
1266 retainInTopLevelEnvs keep_these hpt
1267 = listToUFM [ (mod, expectJust "retain" mb_mod_info)
1269 , let mb_mod_info = lookupUFM hpt mod
1270 , isJust mb_mod_info ]
1272 -- ---------------------------------------------------------------------------
1273 -- Topological sort of the module graph
1276 :: Bool -- Drop hi-boot nodes? (see below)
1280 -- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1281 -- The resulting list of strongly-connected-components is in topologically
1282 -- sorted order, starting with the module(s) at the bottom of the
1283 -- dependency graph (ie compile them first) and ending with the ones at
1286 -- Drop hi-boot nodes (first boolean arg)?
1288 -- False: treat the hi-boot summaries as nodes of the graph,
1289 -- so the graph must be acyclic
1291 -- True: eliminate the hi-boot nodes, and instead pretend
1292 -- the a source-import of Foo is an import of Foo
1293 -- The resulting graph has no hi-boot nodes, but can by cyclic
1295 topSortModuleGraph drop_hs_boot_nodes summaries Nothing
1296 = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
1297 topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
1298 = stronglyConnComp (map vertex_fn (reachable graph root))
1300 -- restrict the graph to just those modules reachable from
1301 -- the specified module. We do this by building a graph with
1302 -- the full set of nodes, and determining the reachable set from
1303 -- the specified node.
1304 (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
1305 (graph, vertex_fn, key_fn) = graphFromEdges' nodes
1307 | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
1308 | otherwise = throwDyn (ProgramError "module does not exist")
1310 moduleGraphNodes :: Bool -> [ModSummary]
1311 -> ([(ModSummary, Int, [Int])], HscSource -> ModuleName -> Maybe Int)
1312 moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
1314 -- Drop hs-boot nodes by using HsSrcFile as the key
1315 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1316 | otherwise = HsBootFile
1318 -- We use integers as the keys for the SCC algorithm
1319 nodes :: [(ModSummary, Int, [Int])]
1320 nodes = [(s, expectJust "topSort" $
1321 lookup_key (ms_hsc_src s) (ms_mod_name s),
1322 out_edge_keys hs_boot_key (map unLoc (ms_srcimps s)) ++
1323 out_edge_keys HsSrcFile (map unLoc (ms_imps s)) ++
1324 (-- see [boot-edges] below
1325 if drop_hs_boot_nodes || ms_hsc_src s == HsBootFile
1327 else case lookup_key HsBootFile (ms_mod_name s) of
1332 , not (isBootSummary s && drop_hs_boot_nodes) ]
1333 -- Drop the hi-boot ones if told to do so
1335 -- [boot-edges] if this is a .hs and there is an equivalent
1336 -- .hs-boot, add a link from the former to the latter. This
1337 -- has the effect of detecting bogus cases where the .hs-boot
1338 -- depends on the .hs, by introducing a cycle. Additionally,
1339 -- it ensures that we will always process the .hs-boot before
1340 -- the .hs, and so the HomePackageTable will always have the
1341 -- most up to date information.
1343 key_map :: NodeMap Int
1344 key_map = listToFM ([(moduleName (ms_mod s), ms_hsc_src s)
1348 lookup_key :: HscSource -> ModuleName -> Maybe Int
1349 lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
1351 out_edge_keys :: HscSource -> [ModuleName] -> [Int]
1352 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1353 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1354 -- the IsBootInterface parameter True; else False
1357 type NodeKey = (ModuleName, HscSource) -- The nodes of the graph are
1358 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1360 msKey :: ModSummary -> NodeKey
1361 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (moduleName mod,boot)
1363 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1364 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1366 nodeMapElts :: NodeMap a -> [a]
1367 nodeMapElts = eltsFM
1369 -- If there are {-# SOURCE #-} imports between strongly connected
1370 -- components in the topological sort, then those imports can
1371 -- definitely be replaced by ordinary non-SOURCE imports: if SOURCE
1372 -- were necessary, then the edge would be part of a cycle.
1373 warnUnnecessarySourceImports :: DynFlags -> [SCC ModSummary] -> IO ()
1374 warnUnnecessarySourceImports dflags sccs =
1375 printBagOfWarnings dflags (listToBag (concat (map (check.flattenSCC) sccs)))
1377 let mods_in_this_cycle = map ms_mod_name ms in
1378 [ warn m i | m <- ms, i <- ms_srcimps m,
1379 unLoc i `notElem` mods_in_this_cycle ]
1381 warn :: ModSummary -> Located ModuleName -> WarnMsg
1382 warn ms (L loc mod) =
1384 (ptext SLIT("Warning: {-# SOURCE #-} unnecessary in import of ")
1385 <+> quotes (ppr mod))
1387 -----------------------------------------------------------------------------
1388 -- Downsweep (dependency analysis)
1390 -- Chase downwards from the specified root set, returning summaries
1391 -- for all home modules encountered. Only follow source-import
1394 -- We pass in the previous collection of summaries, which is used as a
1395 -- cache to avoid recalculating a module summary if the source is
1398 -- The returned list of [ModSummary] nodes has one node for each home-package
1399 -- module, plus one for any hs-boot files. The imports of these nodes
1400 -- are all there, including the imports of non-home-package modules.
1403 -> [ModSummary] -- Old summaries
1404 -> [ModuleName] -- Ignore dependencies on these; treat
1405 -- them as if they were package modules
1406 -> Bool -- True <=> allow multiple targets to have
1407 -- the same module name; this is
1408 -- very useful for ghc -M
1409 -> IO (Maybe [ModSummary])
1410 -- The elts of [ModSummary] all have distinct
1411 -- (Modules, IsBoot) identifiers, unless the Bool is true
1412 -- in which case there can be repeats
1413 downsweep hsc_env old_summaries excl_mods allow_dup_roots
1414 = -- catch error messages and return them
1415 handleDyn (\err_msg -> printBagOfErrors (hsc_dflags hsc_env) (unitBag err_msg) >> return Nothing) $ do
1416 rootSummaries <- mapM getRootSummary roots
1417 let root_map = mkRootMap rootSummaries
1418 checkDuplicates root_map
1419 summs <- loop (concatMap msDeps rootSummaries) root_map
1422 roots = hsc_targets hsc_env
1424 old_summary_map :: NodeMap ModSummary
1425 old_summary_map = mkNodeMap old_summaries
1427 getRootSummary :: Target -> IO ModSummary
1428 getRootSummary (Target (TargetFile file mb_phase) maybe_buf)
1429 = do exists <- doesFileExist file
1431 then summariseFile hsc_env old_summaries file mb_phase maybe_buf
1432 else throwDyn $ mkPlainErrMsg noSrcSpan $
1433 text "can't find file:" <+> text file
1434 getRootSummary (Target (TargetModule modl) maybe_buf)
1435 = do maybe_summary <- summariseModule hsc_env old_summary_map False
1436 (L rootLoc modl) maybe_buf excl_mods
1437 case maybe_summary of
1438 Nothing -> packageModErr modl
1441 rootLoc = mkGeneralSrcSpan FSLIT("<command line>")
1443 -- In a root module, the filename is allowed to diverge from the module
1444 -- name, so we have to check that there aren't multiple root files
1445 -- defining the same module (otherwise the duplicates will be silently
1446 -- ignored, leading to confusing behaviour).
1447 checkDuplicates :: NodeMap [ModSummary] -> IO ()
1448 checkDuplicates root_map
1449 | allow_dup_roots = return ()
1450 | null dup_roots = return ()
1451 | otherwise = multiRootsErr (head dup_roots)
1453 dup_roots :: [[ModSummary]] -- Each at least of length 2
1454 dup_roots = filterOut isSingleton (nodeMapElts root_map)
1456 loop :: [(Located ModuleName,IsBootInterface)]
1457 -- Work list: process these modules
1458 -> NodeMap [ModSummary]
1459 -- Visited set; the range is a list because
1460 -- the roots can have the same module names
1461 -- if allow_dup_roots is True
1463 -- The result includes the worklist, except
1464 -- for those mentioned in the visited set
1465 loop [] done = return (concat (nodeMapElts done))
1466 loop ((wanted_mod, is_boot) : ss) done
1467 | Just summs <- lookupFM done key
1468 = if isSingleton summs then
1471 do { multiRootsErr summs; return [] }
1472 | otherwise = do { mb_s <- summariseModule hsc_env old_summary_map
1473 is_boot wanted_mod Nothing excl_mods
1475 Nothing -> loop ss done
1476 Just s -> loop (msDeps s ++ ss)
1477 (addToFM done key [s]) }
1479 key = (unLoc wanted_mod, if is_boot then HsBootFile else HsSrcFile)
1481 mkRootMap :: [ModSummary] -> NodeMap [ModSummary]
1482 mkRootMap summaries = addListToFM_C (++) emptyFM
1483 [ (msKey s, [s]) | s <- summaries ]
1485 msDeps :: ModSummary -> [(Located ModuleName, IsBootInterface)]
1486 -- (msDeps s) returns the dependencies of the ModSummary s.
1487 -- A wrinkle is that for a {-# SOURCE #-} import we return
1488 -- *both* the hs-boot file
1489 -- *and* the source file
1490 -- as "dependencies". That ensures that the list of all relevant
1491 -- modules always contains B.hs if it contains B.hs-boot.
1492 -- Remember, this pass isn't doing the topological sort. It's
1493 -- just gathering the list of all relevant ModSummaries
1495 concat [ [(m,True), (m,False)] | m <- ms_srcimps s ]
1496 ++ [ (m,False) | m <- ms_imps s ]
1498 -----------------------------------------------------------------------------
1499 -- Summarising modules
1501 -- We have two types of summarisation:
1503 -- * Summarise a file. This is used for the root module(s) passed to
1504 -- cmLoadModules. The file is read, and used to determine the root
1505 -- module name. The module name may differ from the filename.
1507 -- * Summarise a module. We are given a module name, and must provide
1508 -- a summary. The finder is used to locate the file in which the module
1513 -> [ModSummary] -- old summaries
1514 -> FilePath -- source file name
1515 -> Maybe Phase -- start phase
1516 -> Maybe (StringBuffer,ClockTime)
1519 summariseFile hsc_env old_summaries file mb_phase maybe_buf
1520 -- we can use a cached summary if one is available and the
1521 -- source file hasn't changed, But we have to look up the summary
1522 -- by source file, rather than module name as we do in summarise.
1523 | Just old_summary <- findSummaryBySourceFile old_summaries file
1525 let location = ms_location old_summary
1527 -- return the cached summary if the source didn't change
1528 src_timestamp <- case maybe_buf of
1529 Just (_,t) -> return t
1530 Nothing -> getModificationTime file
1531 -- The file exists; we checked in getRootSummary above.
1532 -- If it gets removed subsequently, then this
1533 -- getModificationTime may fail, but that's the right
1536 if ms_hs_date old_summary == src_timestamp
1537 then do -- update the object-file timestamp
1538 obj_timestamp <- getObjTimestamp location False
1539 return old_summary{ ms_obj_date = obj_timestamp }
1547 let dflags = hsc_dflags hsc_env
1549 (dflags', hspp_fn, buf)
1550 <- preprocessFile dflags file mb_phase maybe_buf
1552 (srcimps,the_imps, L _ mod_name) <- getImports dflags' buf hspp_fn
1554 -- Make a ModLocation for this file
1555 location <- mkHomeModLocation dflags mod_name file
1557 -- Tell the Finder cache where it is, so that subsequent calls
1558 -- to findModule will find it, even if it's not on any search path
1559 mod <- addHomeModuleToFinder hsc_env mod_name location
1561 src_timestamp <- case maybe_buf of
1562 Just (_,t) -> return t
1563 Nothing -> getModificationTime file
1564 -- getMofificationTime may fail
1566 obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
1568 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
1569 ms_location = location,
1570 ms_hspp_file = hspp_fn,
1571 ms_hspp_opts = dflags',
1572 ms_hspp_buf = Just buf,
1573 ms_srcimps = srcimps, ms_imps = the_imps,
1574 ms_hs_date = src_timestamp,
1575 ms_obj_date = obj_timestamp })
1577 findSummaryBySourceFile :: [ModSummary] -> FilePath -> Maybe ModSummary
1578 findSummaryBySourceFile summaries file
1579 = case [ ms | ms <- summaries, HsSrcFile <- [ms_hsc_src ms],
1580 expectJust "findSummaryBySourceFile" (ml_hs_file (ms_location ms)) == file ] of
1584 -- Summarise a module, and pick up source and timestamp.
1587 -> NodeMap ModSummary -- Map of old summaries
1588 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
1589 -> Located ModuleName -- Imported module to be summarised
1590 -> Maybe (StringBuffer, ClockTime)
1591 -> [ModuleName] -- Modules to exclude
1592 -> IO (Maybe ModSummary) -- Its new summary
1594 summariseModule hsc_env old_summary_map is_boot (L loc wanted_mod) maybe_buf excl_mods
1595 | wanted_mod `elem` excl_mods
1598 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
1599 = do -- Find its new timestamp; all the
1600 -- ModSummaries in the old map have valid ml_hs_files
1601 let location = ms_location old_summary
1602 src_fn = expectJust "summariseModule" (ml_hs_file location)
1604 -- check the modification time on the source file, and
1605 -- return the cached summary if it hasn't changed. If the
1606 -- file has disappeared, we need to call the Finder again.
1608 Just (_,t) -> check_timestamp old_summary location src_fn t
1610 m <- System.IO.Error.try (getModificationTime src_fn)
1612 Right t -> check_timestamp old_summary location src_fn t
1613 Left e | isDoesNotExistError e -> find_it
1614 | otherwise -> ioError e
1616 | otherwise = find_it
1618 dflags = hsc_dflags hsc_env
1620 hsc_src = if is_boot then HsBootFile else HsSrcFile
1622 check_timestamp old_summary location src_fn src_timestamp
1623 | ms_hs_date old_summary == src_timestamp = do
1624 -- update the object-file timestamp
1625 obj_timestamp <- getObjTimestamp location is_boot
1626 return (Just old_summary{ ms_obj_date = obj_timestamp })
1628 -- source changed: re-summarise.
1629 new_summary location (ms_mod old_summary) src_fn src_timestamp
1632 -- Don't use the Finder's cache this time. If the module was
1633 -- previously a package module, it may have now appeared on the
1634 -- search path, so we want to consider it to be a home module. If
1635 -- the module was previously a home module, it may have moved.
1636 uncacheModule hsc_env wanted_mod
1637 found <- findImportedModule hsc_env wanted_mod Nothing
1640 | isJust (ml_hs_file location) ->
1642 just_found location mod
1644 -- Drop external-pkg
1645 ASSERT(modulePackageId mod /= thisPackage dflags)
1649 err -> noModError dflags loc wanted_mod err
1652 just_found location mod = do
1653 -- Adjust location to point to the hs-boot source file,
1654 -- hi file, object file, when is_boot says so
1655 let location' | is_boot = addBootSuffixLocn location
1656 | otherwise = location
1657 src_fn = expectJust "summarise2" (ml_hs_file location')
1659 -- Check that it exists
1660 -- It might have been deleted since the Finder last found it
1661 maybe_t <- modificationTimeIfExists src_fn
1663 Nothing -> noHsFileErr loc src_fn
1664 Just t -> new_summary location' mod src_fn t
1667 new_summary location mod src_fn src_timestamp
1669 -- Preprocess the source file and get its imports
1670 -- The dflags' contains the OPTIONS pragmas
1671 (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn Nothing maybe_buf
1672 (srcimps, the_imps, L mod_loc mod_name) <- getImports dflags' buf hspp_fn
1674 when (mod_name /= wanted_mod) $
1675 throwDyn $ mkPlainErrMsg mod_loc $
1676 text "file name does not match module name"
1677 <+> quotes (ppr mod_name)
1679 -- Find the object timestamp, and return the summary
1680 obj_timestamp <- getObjTimestamp location is_boot
1682 return (Just ( ModSummary { ms_mod = mod,
1683 ms_hsc_src = hsc_src,
1684 ms_location = location,
1685 ms_hspp_file = hspp_fn,
1686 ms_hspp_opts = dflags',
1687 ms_hspp_buf = Just buf,
1688 ms_srcimps = srcimps,
1690 ms_hs_date = src_timestamp,
1691 ms_obj_date = obj_timestamp }))
1694 getObjTimestamp location is_boot
1695 = if is_boot then return Nothing
1696 else modificationTimeIfExists (ml_obj_file location)
1699 preprocessFile :: DynFlags -> FilePath -> Maybe Phase -> Maybe (StringBuffer,ClockTime)
1700 -> IO (DynFlags, FilePath, StringBuffer)
1701 preprocessFile dflags src_fn mb_phase Nothing
1703 (dflags', hspp_fn) <- preprocess dflags (src_fn, mb_phase)
1704 buf <- hGetStringBuffer hspp_fn
1705 return (dflags', hspp_fn, buf)
1707 preprocessFile dflags src_fn mb_phase (Just (buf, time))
1709 -- case we bypass the preprocessing stage?
1711 local_opts = getOptions buf src_fn
1713 (dflags', errs) <- parseDynamicFlags dflags (map unLoc local_opts)
1717 | Just (Unlit _) <- mb_phase = True
1718 | Nothing <- mb_phase, Unlit _ <- startPhase src_fn = True
1719 -- note: local_opts is only required if there's no Unlit phase
1720 | dopt Opt_Cpp dflags' = True
1721 | dopt Opt_Pp dflags' = True
1724 when needs_preprocessing $
1725 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
1727 return (dflags', src_fn, buf)
1730 -----------------------------------------------------------------------------
1732 -----------------------------------------------------------------------------
1734 noModError :: DynFlags -> SrcSpan -> ModuleName -> FindResult -> IO ab
1735 -- ToDo: we don't have a proper line number for this error
1736 noModError dflags loc wanted_mod err
1737 = throwDyn $ mkPlainErrMsg loc $ cannotFindModule dflags wanted_mod err
1739 noHsFileErr loc path
1740 = throwDyn $ mkPlainErrMsg loc $ text "Can't find" <+> text path
1743 = throwDyn $ mkPlainErrMsg noSrcSpan $
1744 text "module" <+> quotes (ppr mod) <+> text "is a package module"
1746 multiRootsErr :: [ModSummary] -> IO ()
1747 multiRootsErr summs@(summ1:_)
1748 = throwDyn $ mkPlainErrMsg noSrcSpan $
1749 text "module" <+> quotes (ppr mod) <+>
1750 text "is defined in multiple files:" <+>
1751 sep (map text files)
1754 files = map (expectJust "checkDup" . ml_hs_file . ms_location) summs
1756 cyclicModuleErr :: [ModSummary] -> SDoc
1758 = hang (ptext SLIT("Module imports form a cycle for modules:"))
1759 2 (vcat (map show_one ms))
1761 show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
1762 nest 2 $ ptext SLIT("imports:") <+>
1763 (pp_imps HsBootFile (ms_srcimps ms)
1764 $$ pp_imps HsSrcFile (ms_imps ms))]
1765 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
1766 pp_imps src mods = fsep (map (show_mod src) mods)
1769 -- | Inform GHC that the working directory has changed. GHC will flush
1770 -- its cache of module locations, since it may no longer be valid.
1771 -- Note: if you change the working directory, you should also unload
1772 -- the current program (set targets to empty, followed by load).
1773 workingDirectoryChanged :: Session -> IO ()
1774 workingDirectoryChanged s = withSession s $ flushFinderCaches
1776 -- -----------------------------------------------------------------------------
1777 -- inspecting the session
1779 -- | Get the module dependency graph.
1780 getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
1781 getModuleGraph s = withSession s (return . hsc_mod_graph)
1783 isLoaded :: Session -> ModuleName -> IO Bool
1784 isLoaded s m = withSession s $ \hsc_env ->
1785 return $! isJust (lookupUFM (hsc_HPT hsc_env) m)
1787 getBindings :: Session -> IO [TyThing]
1788 getBindings s = withSession s $ \hsc_env ->
1789 -- we have to implement the shadowing behaviour of ic_tmp_ids here
1790 -- (see InteractiveContext) and the quickest way is to use an OccEnv.
1792 tmp_ids = ic_tmp_ids (hsc_IC hsc_env)
1793 filtered = foldr f (const []) tmp_ids emptyUniqSet
1795 | uniq `elementOfUniqSet` set = rest set
1796 | otherwise = AnId id : rest (addOneToUniqSet set uniq)
1797 where uniq = getUnique (nameOccName (idName id))
1801 getPrintUnqual :: Session -> IO PrintUnqualified
1802 getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
1804 -- | Container for information about a 'Module'.
1805 data ModuleInfo = ModuleInfo {
1806 minf_type_env :: TypeEnv,
1807 minf_exports :: NameSet, -- ToDo, [AvailInfo] like ModDetails?
1808 minf_rdr_env :: Maybe GlobalRdrEnv, -- Nothing for a compiled/package mod
1809 minf_instances :: [Instance]
1811 ,minf_modBreaks :: ModBreaks
1813 -- ToDo: this should really contain the ModIface too
1815 -- We don't want HomeModInfo here, because a ModuleInfo applies
1816 -- to package modules too.
1818 -- | Request information about a loaded 'Module'
1819 getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
1820 getModuleInfo s mdl = withSession s $ \hsc_env -> do
1821 let mg = hsc_mod_graph hsc_env
1822 if mdl `elem` map ms_mod mg
1823 then getHomeModuleInfo hsc_env (moduleName mdl)
1825 {- if isHomeModule (hsc_dflags hsc_env) mdl
1827 else -} getPackageModuleInfo hsc_env mdl
1828 -- getPackageModuleInfo will attempt to find the interface, so
1829 -- we don't want to call it for a home module, just in case there
1830 -- was a problem loading the module and the interface doesn't
1831 -- exist... hence the isHomeModule test here. (ToDo: reinstate)
1833 getPackageModuleInfo :: HscEnv -> Module -> IO (Maybe ModuleInfo)
1834 getPackageModuleInfo hsc_env mdl = do
1836 (_msgs, mb_avails) <- getModuleExports hsc_env mdl
1838 Nothing -> return Nothing
1840 eps <- readIORef (hsc_EPS hsc_env)
1842 names = availsToNameSet avails
1844 tys = [ ty | name <- concatMap availNames avails,
1845 Just ty <- [lookupTypeEnv pte name] ]
1847 return (Just (ModuleInfo {
1848 minf_type_env = mkTypeEnv tys,
1849 minf_exports = names,
1850 minf_rdr_env = Just $! nameSetToGlobalRdrEnv names (moduleName mdl),
1851 minf_instances = error "getModuleInfo: instances for package module unimplemented",
1852 minf_modBreaks = emptyModBreaks
1855 -- bogusly different for non-GHCI (ToDo)
1859 getHomeModuleInfo hsc_env mdl =
1860 case lookupUFM (hsc_HPT hsc_env) mdl of
1861 Nothing -> return Nothing
1863 let details = hm_details hmi
1864 return (Just (ModuleInfo {
1865 minf_type_env = md_types details,
1866 minf_exports = availsToNameSet (md_exports details),
1867 minf_rdr_env = mi_globals $! hm_iface hmi,
1868 minf_instances = md_insts details
1870 ,minf_modBreaks = md_modBreaks details
1874 -- | The list of top-level entities defined in a module
1875 modInfoTyThings :: ModuleInfo -> [TyThing]
1876 modInfoTyThings minf = typeEnvElts (minf_type_env minf)
1878 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
1879 modInfoTopLevelScope minf
1880 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
1882 modInfoExports :: ModuleInfo -> [Name]
1883 modInfoExports minf = nameSetToList $! minf_exports minf
1885 -- | Returns the instances defined by the specified module.
1886 -- Warning: currently unimplemented for package modules.
1887 modInfoInstances :: ModuleInfo -> [Instance]
1888 modInfoInstances = minf_instances
1890 modInfoIsExportedName :: ModuleInfo -> Name -> Bool
1891 modInfoIsExportedName minf name = elemNameSet name (minf_exports minf)
1893 modInfoPrintUnqualified :: ModuleInfo -> Maybe PrintUnqualified
1894 modInfoPrintUnqualified minf = fmap mkPrintUnqualified (minf_rdr_env minf)
1896 modInfoLookupName :: Session -> ModuleInfo -> Name -> IO (Maybe TyThing)
1897 modInfoLookupName s minf name = withSession s $ \hsc_env -> do
1898 case lookupTypeEnv (minf_type_env minf) name of
1899 Just tyThing -> return (Just tyThing)
1901 eps <- readIORef (hsc_EPS hsc_env)
1902 return $! lookupType (hsc_dflags hsc_env)
1903 (hsc_HPT hsc_env) (eps_PTE eps) name
1906 modInfoModBreaks = minf_modBreaks
1909 isDictonaryId :: Id -> Bool
1911 = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
1913 -- | Looks up a global name: that is, any top-level name in any
1914 -- visible module. Unlike 'lookupName', lookupGlobalName does not use
1915 -- the interactive context, and therefore does not require a preceding
1917 lookupGlobalName :: Session -> Name -> IO (Maybe TyThing)
1918 lookupGlobalName s name = withSession s $ \hsc_env -> do
1919 eps <- readIORef (hsc_EPS hsc_env)
1920 return $! lookupType (hsc_dflags hsc_env)
1921 (hsc_HPT hsc_env) (eps_PTE eps) name
1923 -- -----------------------------------------------------------------------------
1924 -- Misc exported utils
1926 dataConType :: DataCon -> Type
1927 dataConType dc = idType (dataConWrapId dc)
1929 -- | print a 'NamedThing', adding parentheses if the name is an operator.
1930 pprParenSymName :: NamedThing a => a -> SDoc
1931 pprParenSymName a = parenSymOcc (getOccName a) (ppr (getName a))
1933 -- ----------------------------------------------------------------------------
1938 -- - Data and Typeable instances for HsSyn.
1940 -- ToDo: check for small transformations that happen to the syntax in
1941 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
1943 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
1944 -- to get from TyCons, Ids etc. to TH syntax (reify).
1946 -- :browse will use either lm_toplev or inspect lm_interface, depending
1947 -- on whether the module is interpreted or not.
1949 -- This is for reconstructing refactored source code
1950 -- Calls the lexer repeatedly.
1951 -- ToDo: add comment tokens to token stream
1952 getTokenStream :: Session -> Module -> IO [Located Token]
1955 -- -----------------------------------------------------------------------------
1956 -- Interactive evaluation
1958 -- | Takes a 'ModuleName' and possibly a 'PackageId', and consults the
1959 -- filesystem and package database to find the corresponding 'Module',
1960 -- using the algorithm that is used for an @import@ declaration.
1961 findModule :: Session -> ModuleName -> Maybe PackageId -> IO Module
1962 findModule s mod_name maybe_pkg = withSession s $ \hsc_env ->
1963 findModule' hsc_env mod_name maybe_pkg
1965 findModule' hsc_env mod_name maybe_pkg =
1967 dflags = hsc_dflags hsc_env
1968 hpt = hsc_HPT hsc_env
1969 this_pkg = thisPackage dflags
1971 case lookupUFM hpt mod_name of
1972 Just mod_info -> return (mi_module (hm_iface mod_info))
1973 _not_a_home_module -> do
1974 res <- findImportedModule hsc_env mod_name maybe_pkg
1976 Found _ m | modulePackageId m /= this_pkg -> return m
1977 | otherwise -> throwDyn (CmdLineError (showSDoc $
1978 text "module" <+> pprModule m <+>
1979 text "is not loaded"))
1980 err -> let msg = cannotFindModule dflags mod_name err in
1981 throwDyn (CmdLineError (showSDoc msg))