1 -- -----------------------------------------------------------------------------
3 -- (c) The University of Glasgow, 2005
7 -- -----------------------------------------------------------------------------
13 defaultCleanupHandler,
17 -- * Flags and settings
18 DynFlags(..), DynFlag(..), GhcMode(..), HscTarget(..), dopt,
26 Target(..), TargetId(..),
33 -- * Loading\/compiling the program
35 load, LoadHowMuch(..), SuccessFlag(..), -- also does depanal
36 workingDirectoryChanged,
37 checkModule, CheckedModule(..),
39 -- * Inspecting the module structure of the program
40 ModuleGraph, ModSummary(..),
45 -- * Inspecting modules
52 -- * Interactive evaluation
53 getBindings, getPrintUnqual,
55 setContext, getContext,
58 getInfo, GetInfoResult,
69 -- * Abstract syntax elements
72 Module, mkModule, pprModule,
79 isImplicitId, isDeadBinder,
80 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
82 isPrimOpId, isFCallId,
83 isDataConWorkId, idDataCon,
84 isBottomingId, isDictonaryId,
86 -- ** Type constructors
88 isClassTyCon, isSynTyCon, isNewTyCon,
90 -- ** Data constructors
95 classSCTheta, classTvsFds,
105 GhcException(..), showGhcException,
115 * return error messages rather than printing them.
116 * inline bits of HscMain here to simplify layering: hscGetInfo,
118 * implement second argument to load.
119 * we need to expose DynFlags, so should parseDynamicFlags really be
120 part of this interface?
121 * what StaticFlags should we expose, if any?
124 #include "HsVersions.h"
127 import qualified Linker
128 import Linker ( HValue, extendLinkEnv )
129 import NameEnv ( lookupNameEnv )
130 import TcRnDriver ( mkExportEnv, getModuleContents, tcRnLookupRdrName )
131 import RdrName ( plusGlobalRdrEnv )
132 import HscMain ( hscGetInfo, GetInfoResult, hscParseIdentifier,
133 hscStmt, hscTcExpr, hscKcType )
134 import Type ( tidyType )
135 import VarEnv ( emptyTidyEnv )
136 import GHC.Exts ( unsafeCoerce# )
137 import IfaceSyn ( IfaceDecl )
140 import Packages ( initPackages )
141 import NameSet ( NameSet, nameSetToList )
142 import RdrName ( GlobalRdrEnv )
143 import HsSyn ( HsModule, LHsBinds )
144 import Type ( Kind, Type, dropForAlls )
145 import Id ( Id, idType, isImplicitId, isDeadBinder,
146 isSpecPragmaId, isExportedId, isLocalId, isGlobalId,
148 isPrimOpId, isFCallId,
149 isDataConWorkId, idDataCon,
151 import TyCon ( TyCon, isClassTyCon, isSynTyCon, isNewTyCon )
152 import Class ( Class, classSCTheta, classTvsFds )
153 import DataCon ( DataCon )
154 import Name ( Name, getName, nameModule_maybe )
155 import RdrName ( RdrName, gre_name, globalRdrEnvElts )
156 import NameEnv ( nameEnvElts )
157 import SrcLoc ( Located(..) )
158 import DriverPipeline
159 import DriverPhases ( Phase(..), isHaskellSrcFilename, startPhase )
160 import GetImports ( getImports )
161 import Packages ( isHomePackage )
163 import HscMain ( newHscEnv, hscFileCheck, HscResult(..) )
167 import SysTools ( initSysTools, cleanTempFiles )
172 import ErrUtils ( showPass, Messages, putMsg, debugTraceMsg )
173 import qualified ErrUtils
175 import StringBuffer ( StringBuffer, hGetStringBuffer )
177 import SysTools ( cleanTempFilesExcept )
178 import BasicTypes ( SuccessFlag(..), succeeded, failed )
179 import Maybes ( orElse, expectJust, mapCatMaybes )
180 import TcType ( tcSplitSigmaTy, isDictTy )
182 import Directory ( getModificationTime, doesFileExist )
183 import Maybe ( isJust, isNothing, fromJust, fromMaybe, catMaybes )
184 import Maybes ( expectJust )
185 import List ( partition, nub )
186 import qualified List
187 import Monad ( unless, when, foldM )
188 import System ( exitWith, ExitCode(..) )
189 import Time ( ClockTime )
190 import EXCEPTION as Exception hiding (handle)
193 import Prelude hiding (init)
195 -- -----------------------------------------------------------------------------
196 -- Exception handlers
198 -- | Install some default exception handlers and run the inner computation.
199 -- Unless you want to handle exceptions yourself, you should wrap this around
200 -- the top level of your program. The default handlers output the error
201 -- message(s) to stderr and exit cleanly.
202 defaultErrorHandler :: IO a -> IO a
203 defaultErrorHandler inner =
204 -- top-level exception handler: any unrecognised exception is a compiler bug.
205 handle (\exception -> do
208 -- an IO exception probably isn't our fault, so don't panic
209 IOException _ -> putMsg (show exception)
210 AsyncException StackOverflow ->
211 putMsg "stack overflow: use +RTS -K<size> to increase it"
212 _other -> putMsg (show (Panic (show exception)))
213 exitWith (ExitFailure 1)
216 -- all error messages are propagated as exceptions
217 handleDyn (\dyn -> do
220 PhaseFailed _ code -> exitWith code
221 Interrupted -> exitWith (ExitFailure 1)
222 _ -> do putMsg (show (dyn :: GhcException))
223 exitWith (ExitFailure 1)
227 -- | Install a default cleanup handler to remove temporary files
228 -- deposited by a GHC run. This is seperate from
229 -- 'defaultErrorHandler', because you might want to override the error
230 -- handling, but still get the ordinary cleanup behaviour.
231 defaultCleanupHandler :: DynFlags -> IO a -> IO a
232 defaultCleanupHandler dflags inner =
233 -- make sure we clean up after ourselves
234 later (unless (dopt Opt_KeepTmpFiles dflags) $
235 cleanTempFiles dflags)
236 -- exceptions will be blocked while we clean the temporary files,
237 -- so there shouldn't be any difficulty if we receive further
242 -- | Initialises GHC. This must be done /once/ only. Takes the
243 -- command-line arguments. All command-line arguments which aren't
244 -- understood by GHC will be returned.
246 init :: [String] -> IO [String]
249 installSignalHandlers
251 -- Grab the -B option if there is one
252 let (minusB_args, argv1) = partition (prefixMatch "-B") args
253 dflags0 <- initSysTools minusB_args defaultDynFlags
254 writeIORef v_initDynFlags dflags0
256 -- Parse the static flags
257 argv2 <- parseStaticFlags argv1
260 GLOBAL_VAR(v_initDynFlags, error "initDynFlags", DynFlags)
261 -- stores the DynFlags between the call to init and subsequent
262 -- calls to newSession.
264 -- | Starts a new session. A session consists of a set of loaded
265 -- modules, a set of options (DynFlags), and an interactive context.
266 -- ToDo: GhcMode should say "keep typechecked code" and\/or "keep renamed
268 newSession :: GhcMode -> IO Session
270 dflags0 <- readIORef v_initDynFlags
271 dflags <- initDynFlags dflags0
272 env <- newHscEnv dflags{ ghcMode=mode }
276 -- tmp: this breaks the abstraction, but required because DriverMkDepend
277 -- needs to call the Finder. ToDo: untangle this.
278 sessionHscEnv :: Session -> IO HscEnv
279 sessionHscEnv (Session ref) = readIORef ref
281 withSession :: Session -> (HscEnv -> IO a) -> IO a
282 withSession (Session ref) f = do h <- readIORef ref; f h
284 modifySession :: Session -> (HscEnv -> HscEnv) -> IO ()
285 modifySession (Session ref) f = do h <- readIORef ref; writeIORef ref $! f h
287 -- -----------------------------------------------------------------------------
290 -- | Grabs the DynFlags from the Session
291 getSessionDynFlags :: Session -> IO DynFlags
292 getSessionDynFlags s = withSession s (return . hsc_dflags)
294 -- | Updates the DynFlags in a Session
295 setSessionDynFlags :: Session -> DynFlags -> IO ()
296 setSessionDynFlags s dflags = modifySession s (\h -> h{ hsc_dflags = dflags })
298 -- | Messages during compilation (eg. warnings and progress messages)
299 -- are reported using this callback. By default, these messages are
300 -- printed to stderr.
301 setMsgHandler :: (String -> IO ()) -> IO ()
302 setMsgHandler = ErrUtils.setMsgHandler
304 -- -----------------------------------------------------------------------------
307 -- ToDo: think about relative vs. absolute file paths. And what
308 -- happens when the current directory changes.
310 -- | Sets the targets for this session. Each target may be a module name
311 -- or a filename. The targets correspond to the set of root modules for
312 -- the program\/library. Unloading the current program is achieved by
313 -- setting the current set of targets to be empty, followed by load.
314 setTargets :: Session -> [Target] -> IO ()
315 setTargets s targets = modifySession s (\h -> h{ hsc_targets = targets })
317 -- | returns the current set of targets
318 getTargets :: Session -> IO [Target]
319 getTargets s = withSession s (return . hsc_targets)
321 -- | Add another target
322 addTarget :: Session -> Target -> IO ()
324 = modifySession s (\h -> h{ hsc_targets = target : hsc_targets h })
327 removeTarget :: Session -> TargetId -> IO ()
328 removeTarget s target_id
329 = modifySession s (\h -> h{ hsc_targets = filter (hsc_targets h) })
331 filter targets = [ t | t@(Target id _) <- targets, id /= target_id ]
333 -- Attempts to guess what Target a string refers to. This function implements
334 -- the --make/GHCi command-line syntax for filenames:
336 -- - if the string looks like a Haskell source filename, then interpret
338 -- - if adding a .hs or .lhs suffix yields the name of an existing file,
340 -- - otherwise interpret the string as a module name
342 guessTarget :: String -> IO Target
344 | isHaskellSrcFilename file
345 = return (Target (TargetFile file) Nothing)
347 = do exists <- doesFileExist hs_file
348 if exists then return (Target (TargetFile hs_file) Nothing) else do
349 exists <- doesFileExist lhs_file
350 if exists then return (Target (TargetFile lhs_file) Nothing) else do
351 return (Target (TargetModule (mkModule file)) Nothing)
353 hs_file = file ++ ".hs"
354 lhs_file = file ++ ".lhs"
356 -- -----------------------------------------------------------------------------
357 -- Loading the program
359 -- Perform a dependency analysis starting from the current targets
360 -- and update the session with the new module graph.
361 depanal :: Session -> [Module] -> IO ()
362 depanal (Session ref) excluded_mods = do
363 hsc_env <- readIORef ref
365 dflags = hsc_dflags hsc_env
366 gmode = ghcMode (hsc_dflags hsc_env)
367 targets = hsc_targets hsc_env
368 old_graph = hsc_mod_graph hsc_env
370 showPass dflags "Chasing dependencies"
371 when (gmode == BatchCompile) $
372 debugTraceMsg dflags 1 (showSDoc (hcat [
373 text "Chasing modules from: ",
374 hcat (punctuate comma (map pprTarget targets))]))
376 graph <- downsweep hsc_env old_graph excluded_mods
377 writeIORef ref hsc_env{ hsc_mod_graph=graph }
380 -- | The result of load.
382 = LoadOk Errors -- ^ all specified targets were loaded successfully.
383 | LoadFailed Errors -- ^ not all modules were loaded.
385 type Errors = [String]
387 data ErrMsg = ErrMsg {
388 errMsgSeverity :: Severity, -- warning, error, etc.
389 errMsgSpans :: [SrcSpan],
390 errMsgShortDoc :: Doc,
391 errMsgExtraInfo :: Doc
398 | LoadDependenciesOf Module
400 -- | Try to load the program. If a Module is supplied, then just
401 -- attempt to load up to this target. If no Module is supplied,
402 -- then try to load all targets.
403 load :: Session -> LoadHowMuch -> IO SuccessFlag
404 load s@(Session ref) how_much
406 -- Dependency analysis first. Note that this fixes the module graph:
407 -- even if we don't get a fully successful upsweep, the full module
408 -- graph is still retained in the Session. We can tell which modules
409 -- were successfully loaded by inspecting the Session's HPT.
412 hsc_env <- readIORef ref
414 let hpt1 = hsc_HPT hsc_env
415 let dflags = hsc_dflags hsc_env
416 let mod_graph = hsc_mod_graph hsc_env
418 let ghci_mode = ghcMode (hsc_dflags hsc_env) -- this never changes
419 let verb = verbosity dflags
421 -- The "bad" boot modules are the ones for which we have
422 -- B.hs-boot in the module graph, but no B.hs
423 -- The downsweep should have ensured this does not happen
425 let all_home_mods = [ms_mod s | s <- mod_graph, not (isBootSummary s)]
426 bad_boot_mods = [s | s <- mod_graph, isBootSummary s,
427 not (ms_mod s `elem` all_home_mods)]
428 ASSERT( null bad_boot_mods ) return ()
430 -- mg2_with_srcimps drops the hi-boot nodes, returning a
431 -- graph with cycles. Among other things, it is used for
432 -- backing out partially complete cycles following a failed
433 -- upsweep, and for removing from hpt all the modules
434 -- not in strict downwards closure, during calls to compile.
435 let mg2_with_srcimps :: [SCC ModSummary]
436 mg2_with_srcimps = topSortModuleGraph True mod_graph Nothing
438 -- check the stability property for each module.
439 stable_mods@(stable_obj,stable_bco)
440 | BatchCompile <- ghci_mode = ([],[])
441 | otherwise = checkStability hpt1 mg2_with_srcimps all_home_mods
443 -- prune bits of the HPT which are definitely redundant now,
445 pruned_hpt = pruneHomePackageTable hpt1
446 (flattenSCCs mg2_with_srcimps)
451 debugTraceMsg dflags 2 (showSDoc (text "Stable obj:" <+> ppr stable_obj $$
452 text "Stable BCO:" <+> ppr stable_bco))
454 -- Unload any modules which are going to be re-linked this time around.
455 let stable_linkables = [ linkable
456 | m <- stable_obj++stable_bco,
457 Just hmi <- [lookupModuleEnv pruned_hpt m],
458 Just linkable <- [hm_linkable hmi] ]
459 unload hsc_env stable_linkables
461 -- We could at this point detect cycles which aren't broken by
462 -- a source-import, and complain immediately, but it seems better
463 -- to let upsweep_mods do this, so at least some useful work gets
464 -- done before the upsweep is abandoned.
465 --hPutStrLn stderr "after tsort:\n"
466 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
468 -- Now do the upsweep, calling compile for each module in
469 -- turn. Final result is version 3 of everything.
471 -- Topologically sort the module graph, this time including hi-boot
472 -- nodes, and possibly just including the portion of the graph
473 -- reachable from the module specified in the 2nd argument to load.
474 -- This graph should be cycle-free.
475 -- If we're restricting the upsweep to a portion of the graph, we
476 -- also want to retain everything that is still stable.
477 let full_mg :: [SCC ModSummary]
478 full_mg = topSortModuleGraph False mod_graph Nothing
480 maybe_top_mod = case how_much of
482 LoadDependenciesOf m -> Just m
485 partial_mg0 :: [SCC ModSummary]
486 partial_mg0 = topSortModuleGraph False mod_graph maybe_top_mod
488 -- LoadDependenciesOf m: we want the upsweep to stop just
489 -- short of the specified module (unless the specified module
492 | LoadDependenciesOf mod <- how_much
493 = ASSERT( case last partial_mg0 of
494 AcyclicSCC ms -> ms_mod ms == mod; _ -> False )
495 List.init partial_mg0
501 | AcyclicSCC ms <- full_mg,
502 ms_mod ms `elem` stable_obj++stable_bco,
503 ms_mod ms `notElem` [ ms_mod ms' |
504 AcyclicSCC ms' <- partial_mg ] ]
506 mg = stable_mg ++ partial_mg
508 -- clean up between compilations
509 let cleanup = cleanTempFilesExcept dflags
510 (ppFilesFromSummaries (flattenSCCs mg2_with_srcimps))
512 (upsweep_ok, hsc_env1, modsUpswept)
513 <- upsweep (hsc_env { hsc_HPT = emptyHomePackageTable })
514 pruned_hpt stable_mods cleanup mg
516 -- Make modsDone be the summaries for each home module now
517 -- available; this should equal the domain of hpt3.
518 -- Get in in a roughly top .. bottom order (hence reverse).
520 let modsDone = reverse modsUpswept
522 -- Try and do linking in some form, depending on whether the
523 -- upsweep was completely or only partially successful.
525 if succeeded upsweep_ok
528 -- Easy; just relink it all.
529 do debugTraceMsg dflags 2 "Upsweep completely successful."
531 -- Clean up after ourselves
532 cleanTempFilesExcept dflags (ppFilesFromSummaries modsDone)
534 -- Issue a warning for the confusing case where the user
535 -- said '-o foo' but we're not going to do any linking.
536 -- We attempt linking if either (a) one of the modules is
537 -- called Main, or (b) the user said -no-hs-main, indicating
538 -- that main() is going to come from somewhere else.
540 let ofile = outputFile dflags
541 let no_hs_main = dopt Opt_NoHsMain dflags
542 let mb_main_mod = mainModIs dflags
544 main_mod = mb_main_mod `orElse` "Main"
546 = any ((==main_mod).moduleUserString.ms_mod)
548 do_linking = a_root_is_Main || no_hs_main
550 when (ghci_mode == BatchCompile && isJust ofile && not do_linking) $
551 debugTraceMsg dflags 1 ("Warning: output was redirected with -o, " ++
552 "but no output will be generated\n" ++
553 "because there is no " ++ main_mod ++ " module.")
555 -- link everything together
556 linkresult <- link ghci_mode dflags do_linking (hsc_HPT hsc_env1)
558 loadFinish Succeeded linkresult ref hsc_env1
561 -- Tricky. We need to back out the effects of compiling any
562 -- half-done cycles, both so as to clean up the top level envs
563 -- and to avoid telling the interactive linker to link them.
564 do debugTraceMsg dflags 2 "Upsweep partially successful."
567 = map ms_mod modsDone
568 let mods_to_zap_names
569 = findPartiallyCompletedCycles modsDone_names
572 = filter ((`notElem` mods_to_zap_names).ms_mod)
575 let hpt4 = retainInTopLevelEnvs (map ms_mod mods_to_keep)
578 -- Clean up after ourselves
579 cleanTempFilesExcept dflags (ppFilesFromSummaries mods_to_keep)
581 -- there should be no Nothings where linkables should be, now
582 ASSERT(all (isJust.hm_linkable)
583 (moduleEnvElts (hsc_HPT hsc_env))) do
585 -- Link everything together
586 linkresult <- link ghci_mode dflags False hpt4
588 let hsc_env4 = hsc_env1{ hsc_HPT = hpt4 }
589 loadFinish Failed linkresult ref hsc_env4
591 -- Finish up after a load.
593 -- If the link failed, unload everything and return.
594 loadFinish all_ok Failed ref hsc_env
595 = do unload hsc_env []
596 writeIORef ref $! discardProg hsc_env
599 -- Empty the interactive context and set the module context to the topmost
600 -- newly loaded module, or the Prelude if none were loaded.
601 loadFinish all_ok Succeeded ref hsc_env
602 = do writeIORef ref $! hsc_env{ hsc_IC = emptyInteractiveContext }
606 -- Forget the current program, but retain the persistent info in HscEnv
607 discardProg :: HscEnv -> HscEnv
609 = hsc_env { hsc_mod_graph = emptyMG,
610 hsc_IC = emptyInteractiveContext,
611 hsc_HPT = emptyHomePackageTable }
613 -- used to fish out the preprocess output files for the purposes of
614 -- cleaning up. The preprocessed file *might* be the same as the
615 -- source file, but that doesn't do any harm.
616 ppFilesFromSummaries summaries = [ fn | Just fn <- map ms_hspp_file summaries ]
618 -- -----------------------------------------------------------------------------
622 CheckedModule { parsedSource :: ParsedSource,
623 -- ToDo: renamedSource
624 typecheckedSource :: Maybe TypecheckedSource,
625 checkedModuleInfo :: Maybe ModuleInfo
628 type ParsedSource = Located (HsModule RdrName)
629 type TypecheckedSource = LHsBinds Id
631 -- | This is the way to get access to parsed and typechecked source code
632 -- for a module. 'checkModule' loads all the dependencies of the specified
633 -- module in the Session, and then attempts to typecheck the module. If
634 -- successful, it returns the abstract syntax for the module.
635 checkModule :: Session -> Module -> (Messages -> IO ())
636 -> IO (Maybe CheckedModule)
637 checkModule session@(Session ref) mod msg_act = do
638 -- load up the dependencies first
639 r <- load session (LoadDependenciesOf mod)
640 if (failed r) then return Nothing else do
642 -- now parse & typecheck the module
643 hsc_env <- readIORef ref
644 let mg = hsc_mod_graph hsc_env
645 case [ ms | ms <- mg, ms_mod ms == mod ] of
648 r <- hscFileCheck hsc_env msg_act ms
652 HscChecked parsed Nothing ->
653 return (Just (CheckedModule parsed Nothing Nothing))
654 HscChecked parsed (Just (tc_binds, rdr_env, details)) -> do
655 let minf = ModuleInfo {
656 minf_details = details,
657 minf_rdr_env = Just rdr_env
659 return (Just (CheckedModule {
660 parsedSource = parsed,
661 typecheckedSource = Just tc_binds,
662 checkedModuleInfo = Just minf }))
664 -- ---------------------------------------------------------------------------
667 unload :: HscEnv -> [Linkable] -> IO ()
668 unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
669 = case ghcMode (hsc_dflags hsc_env) of
670 BatchCompile -> return ()
671 JustTypecheck -> return ()
673 Interactive -> Linker.unload (hsc_dflags hsc_env) stable_linkables
675 Interactive -> panic "unload: no interpreter"
677 other -> panic "unload: strange mode"
679 -- -----------------------------------------------------------------------------
683 Stability tells us which modules definitely do not need to be recompiled.
684 There are two main reasons for having stability:
686 - avoid doing a complete upsweep of the module graph in GHCi when
687 modules near the bottom of the tree have not changed.
689 - to tell GHCi when it can load object code: we can only load object code
690 for a module when we also load object code fo all of the imports of the
691 module. So we need to know that we will definitely not be recompiling
692 any of these modules, and we can use the object code.
694 NB. stability is of no importance to BatchCompile at all, only Interactive.
695 (ToDo: what about JustTypecheck?)
697 The stability check is as follows. Both stableObject and
698 stableBCO are used during the upsweep phase later.
701 stable m = stableObject m || stableBCO m
704 all stableObject (imports m)
705 && old linkable does not exist, or is == on-disk .o
706 && date(on-disk .o) > date(.hs)
709 all stable (imports m)
710 && date(BCO) > date(.hs)
713 These properties embody the following ideas:
715 - if a module is stable:
716 - if it has been compiled in a previous pass (present in HPT)
717 then it does not need to be compiled or re-linked.
718 - if it has not been compiled in a previous pass,
719 then we only need to read its .hi file from disk and
720 link it to produce a ModDetails.
722 - if a modules is not stable, we will definitely be at least
723 re-linking, and possibly re-compiling it during the upsweep.
724 All non-stable modules can (and should) therefore be unlinked
727 - Note that objects are only considered stable if they only depend
728 on other objects. We can't link object code against byte code.
732 :: HomePackageTable -- HPT from last compilation
733 -> [SCC ModSummary] -- current module graph (cyclic)
734 -> [Module] -- all home modules
735 -> ([Module], -- stableObject
736 [Module]) -- stableBCO
738 checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
740 checkSCC (stable_obj, stable_bco) scc0
741 | stableObjects = (scc_mods ++ stable_obj, stable_bco)
742 | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
743 | otherwise = (stable_obj, stable_bco)
745 scc = flattenSCC scc0
746 scc_mods = map ms_mod scc
747 home_module m = m `elem` all_home_mods && m `notElem` scc_mods
749 scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
750 -- all imports outside the current SCC, but in the home pkg
752 stable_obj_imps = map (`elem` stable_obj) scc_allimps
753 stable_bco_imps = map (`elem` stable_bco) scc_allimps
760 and (zipWith (||) stable_obj_imps stable_bco_imps)
764 | Just t <- ms_obj_date ms = t >= ms_hs_date ms
768 same_as_prev t = case lookupModuleEnv hpt (ms_mod ms) of
770 Just hmi | Just l <- hm_linkable hmi
771 -> isObjectLinkable l && t == linkableTime l
772 -- why '>=' rather than '>' above? If the filesystem stores
773 -- times to the nearset second, we may occasionally find that
774 -- the object & source have the same modification time,
775 -- especially if the source was automatically generated
776 -- and compiled. Using >= is slightly unsafe, but it matches
780 = case lookupModuleEnv hpt (ms_mod ms) of
782 Just hmi | Just l <- hm_linkable hmi ->
783 not (isObjectLinkable l) &&
784 linkableTime l >= ms_hs_date ms
786 ms_allimps :: ModSummary -> [Module]
787 ms_allimps ms = ms_srcimps ms ++ ms_imps ms
789 -- -----------------------------------------------------------------------------
790 -- Prune the HomePackageTable
792 -- Before doing an upsweep, we can throw away:
794 -- - For non-stable modules:
795 -- - all ModDetails, all linked code
796 -- - all unlinked code that is out of date with respect to
799 -- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
800 -- space at the end of the upsweep, because the topmost ModDetails of the
801 -- old HPT holds on to the entire type environment from the previous
804 pruneHomePackageTable
807 -> ([Module],[Module])
810 pruneHomePackageTable hpt summ (stable_obj, stable_bco)
811 = mapModuleEnv prune hpt
813 | is_stable modl = hmi'
814 | otherwise = hmi'{ hm_details = emptyModDetails }
816 modl = mi_module (hm_iface hmi)
817 hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
818 = hmi{ hm_linkable = Nothing }
821 where ms = expectJust "prune" (lookupModuleEnv ms_map modl)
823 ms_map = mkModuleEnv [(ms_mod ms, ms) | ms <- summ]
825 is_stable m = m `elem` stable_obj || m `elem` stable_bco
827 -- -----------------------------------------------------------------------------
829 -- Return (names of) all those in modsDone who are part of a cycle
830 -- as defined by theGraph.
831 findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
832 findPartiallyCompletedCycles modsDone theGraph
836 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
837 chew ((CyclicSCC vs):rest)
838 = let names_in_this_cycle = nub (map ms_mod vs)
840 = nub ([done | done <- modsDone,
841 done `elem` names_in_this_cycle])
842 chewed_rest = chew rest
844 if notNull mods_in_this_cycle
845 && length mods_in_this_cycle < length names_in_this_cycle
846 then mods_in_this_cycle ++ chewed_rest
849 -- -----------------------------------------------------------------------------
852 -- This is where we compile each module in the module graph, in a pass
853 -- from the bottom to the top of the graph.
855 -- There better had not be any cyclic groups here -- we check for them.
858 :: HscEnv -- Includes initially-empty HPT
859 -> HomePackageTable -- HPT from last time round (pruned)
860 -> ([Module],[Module]) -- stable modules (see checkStability)
861 -> IO () -- How to clean up unwanted tmp files
862 -> [SCC ModSummary] -- Mods to do (the worklist)
864 HscEnv, -- With an updated HPT
865 [ModSummary]) -- Mods which succeeded
867 upsweep hsc_env old_hpt stable_mods cleanup
869 = return (Succeeded, hsc_env, [])
871 upsweep hsc_env old_hpt stable_mods cleanup
873 = do putMsg (showSDoc (cyclicModuleErr ms))
874 return (Failed, hsc_env, [])
876 upsweep hsc_env old_hpt stable_mods cleanup
877 (AcyclicSCC mod:mods)
878 = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
879 -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
880 -- (moduleEnvElts (hsc_HPT hsc_env)))
882 mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods mod
884 cleanup -- Remove unwanted tmp files between compilations
887 Nothing -> return (Failed, hsc_env, [])
889 { let this_mod = ms_mod mod
891 -- Add new info to hsc_env
892 hpt1 = extendModuleEnv (hsc_HPT hsc_env)
894 hsc_env1 = hsc_env { hsc_HPT = hpt1 }
896 -- Space-saving: delete the old HPT entry
897 -- for mod BUT if mod is a hs-boot
898 -- node, don't delete it. For the
899 -- interface, the HPT entry is probaby for the
900 -- main Haskell source file. Deleting it
901 -- would force .. (what?? --SDM)
902 old_hpt1 | isBootSummary mod = old_hpt
903 | otherwise = delModuleEnv old_hpt this_mod
905 ; (restOK, hsc_env2, modOKs)
906 <- upsweep hsc_env1 old_hpt1 stable_mods cleanup mods
907 ; return (restOK, hsc_env2, mod:modOKs)
911 -- Compile a single module. Always produce a Linkable for it if
912 -- successful. If no compilation happened, return the old Linkable.
913 upsweep_mod :: HscEnv
915 -> ([Module],[Module])
917 -> IO (Maybe HomeModInfo) -- Nothing => Failed
919 upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) summary
922 this_mod = ms_mod summary
923 mb_obj_date = ms_obj_date summary
924 obj_fn = ml_obj_file (ms_location summary)
925 hs_date = ms_hs_date summary
927 compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
928 compile_it = upsweep_compile hsc_env old_hpt this_mod summary
930 case ghcMode (hsc_dflags hsc_env) of
933 -- Batch-compilating is easy: just check whether we have
934 -- an up-to-date object file. If we do, then the compiler
935 -- needs to do a recompilation check.
936 _ | Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
938 findObjectLinkable this_mod obj_fn obj_date
939 compile_it (Just linkable)
946 _ | is_stable_obj, isJust old_hmi ->
948 -- object is stable, and we have an entry in the
949 -- old HPT: nothing to do
951 | is_stable_obj, isNothing old_hmi -> do
953 findObjectLinkable this_mod obj_fn
954 (expectJust "upseep1" mb_obj_date)
955 compile_it (Just linkable)
956 -- object is stable, but we need to load the interface
957 -- off disk to make a HMI.
960 ASSERT(isJust old_hmi) -- must be in the old_hpt
962 -- BCO is stable: nothing to do
964 | Just hmi <- old_hmi,
965 Just l <- hm_linkable hmi, not (isObjectLinkable l),
966 linkableTime l >= ms_hs_date summary ->
968 -- we have an old BCO that is up to date with respect
969 -- to the source: do a recompilation check as normal.
973 -- no existing code at all: we must recompile.
975 is_stable_obj = this_mod `elem` stable_obj
976 is_stable_bco = this_mod `elem` stable_bco
978 old_hmi = lookupModuleEnv old_hpt this_mod
980 -- Run hsc to compile a module
981 upsweep_compile hsc_env old_hpt this_mod summary mb_old_linkable = do
983 -- The old interface is ok if it's in the old HPT
984 -- a) we're compiling a source file, and the old HPT
985 -- entry is for a source file
986 -- b) we're compiling a hs-boot file
987 -- Case (b) allows an hs-boot file to get the interface of its
988 -- real source file on the second iteration of the compilation
989 -- manager, but that does no harm. Otherwise the hs-boot file
990 -- will always be recompiled
993 = case lookupModuleEnv old_hpt this_mod of
995 Just hm_info | isBootSummary summary -> Just iface
996 | not (mi_boot iface) -> Just iface
997 | otherwise -> Nothing
999 iface = hm_iface hm_info
1001 compresult <- compile hsc_env summary mb_old_linkable mb_old_iface
1004 -- Compilation failed. Compile may still have updated the PCS, tho.
1005 CompErrs -> return Nothing
1007 -- Compilation "succeeded", and may or may not have returned a new
1008 -- linkable (depending on whether compilation was actually performed
1010 CompOK new_details new_iface new_linkable
1011 -> do let new_info = HomeModInfo { hm_iface = new_iface,
1012 hm_details = new_details,
1013 hm_linkable = new_linkable }
1014 return (Just new_info)
1017 -- Filter modules in the HPT
1018 retainInTopLevelEnvs :: [Module] -> HomePackageTable -> HomePackageTable
1019 retainInTopLevelEnvs keep_these hpt
1020 = mkModuleEnv [ (mod, expectJust "retain" mb_mod_info)
1022 , let mb_mod_info = lookupModuleEnv hpt mod
1023 , isJust mb_mod_info ]
1025 -- ---------------------------------------------------------------------------
1026 -- Topological sort of the module graph
1029 :: Bool -- Drop hi-boot nodes? (see below)
1033 -- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
1034 -- The resulting list of strongly-connected-components is in topologically
1035 -- sorted order, starting with the module(s) at the bottom of the
1036 -- dependency graph (ie compile them first) and ending with the ones at
1039 -- Drop hi-boot nodes (first boolean arg)?
1041 -- False: treat the hi-boot summaries as nodes of the graph,
1042 -- so the graph must be acyclic
1044 -- True: eliminate the hi-boot nodes, and instead pretend
1045 -- the a source-import of Foo is an import of Foo
1046 -- The resulting graph has no hi-boot nodes, but can by cyclic
1048 topSortModuleGraph drop_hs_boot_nodes summaries Nothing
1049 = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
1050 topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
1051 = stronglyConnComp (map vertex_fn (reachable graph root))
1053 -- restrict the graph to just those modules reachable from
1054 -- the specified module. We do this by building a graph with
1055 -- the full set of nodes, and determining the reachable set from
1056 -- the specified node.
1057 (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
1058 (graph, vertex_fn, key_fn) = graphFromEdges' nodes
1060 | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
1061 | otherwise = throwDyn (ProgramError "module does not exist")
1063 moduleGraphNodes :: Bool -> [ModSummary]
1064 -> ([(ModSummary, Int, [Int])], HscSource -> Module -> Maybe Int)
1065 moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
1067 -- Drop hs-boot nodes by using HsSrcFile as the key
1068 hs_boot_key | drop_hs_boot_nodes = HsSrcFile
1069 | otherwise = HsBootFile
1071 -- We use integers as the keys for the SCC algorithm
1072 nodes :: [(ModSummary, Int, [Int])]
1073 nodes = [(s, expectJust "topSort" (lookup_key (ms_hsc_src s) (ms_mod s)),
1074 out_edge_keys hs_boot_key (ms_srcimps s) ++
1075 out_edge_keys HsSrcFile (ms_imps s) )
1077 , not (isBootSummary s && drop_hs_boot_nodes) ]
1078 -- Drop the hi-boot ones if told to do so
1080 key_map :: NodeMap Int
1081 key_map = listToFM ([(ms_mod s, ms_hsc_src s) | s <- summaries]
1084 lookup_key :: HscSource -> Module -> Maybe Int
1085 lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
1087 out_edge_keys :: HscSource -> [Module] -> [Int]
1088 out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
1089 -- If we want keep_hi_boot_nodes, then we do lookup_key with
1090 -- the IsBootInterface parameter True; else False
1093 type NodeKey = (Module, HscSource) -- The nodes of the graph are
1094 type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
1096 msKey :: ModSummary -> NodeKey
1097 msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (mod,boot)
1099 emptyNodeMap :: NodeMap a
1100 emptyNodeMap = emptyFM
1102 mkNodeMap :: [ModSummary] -> NodeMap ModSummary
1103 mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
1105 nodeMapElts :: NodeMap a -> [a]
1106 nodeMapElts = eltsFM
1108 -- -----------------------------------------------------------------
1109 -- The unlinked image
1111 -- The compilation manager keeps a list of compiled, but as-yet unlinked
1112 -- binaries (byte code or object code). Even when it links bytecode
1113 -- it keeps the unlinked version so it can re-link it later without
1116 type UnlinkedImage = [Linkable] -- the unlinked images (should be a set, really)
1118 findModuleLinkable_maybe :: [Linkable] -> Module -> Maybe Linkable
1119 findModuleLinkable_maybe lis mod
1120 = case [LM time nm us | LM time nm us <- lis, nm == mod] of
1123 many -> pprPanic "findModuleLinkable" (ppr mod)
1125 delModuleLinkable :: [Linkable] -> Module -> [Linkable]
1126 delModuleLinkable ls mod = [ l | l@(LM _ nm _) <- ls, nm /= mod ]
1128 -----------------------------------------------------------------------------
1129 -- Downsweep (dependency analysis)
1131 -- Chase downwards from the specified root set, returning summaries
1132 -- for all home modules encountered. Only follow source-import
1135 -- We pass in the previous collection of summaries, which is used as a
1136 -- cache to avoid recalculating a module summary if the source is
1139 -- The returned list of [ModSummary] nodes has one node for each home-package
1140 -- module, plus one for any hs-boot files. The imports of these nodes
1141 -- are all there, including the imports of non-home-package modules.
1144 -> [ModSummary] -- Old summaries
1145 -> [Module] -- Ignore dependencies on these; treat them as
1146 -- if they were package modules
1148 downsweep hsc_env old_summaries excl_mods
1149 = do rootSummaries <- mapM getRootSummary roots
1150 checkDuplicates rootSummaries
1151 loop (concatMap msDeps rootSummaries)
1152 (mkNodeMap rootSummaries)
1154 roots = hsc_targets hsc_env
1156 old_summary_map :: NodeMap ModSummary
1157 old_summary_map = mkNodeMap old_summaries
1159 getRootSummary :: Target -> IO ModSummary
1160 getRootSummary (Target (TargetFile file) maybe_buf)
1161 = do exists <- doesFileExist file
1162 if exists then summariseFile hsc_env file maybe_buf else do
1163 throwDyn (CmdLineError ("can't find file: " ++ file))
1164 getRootSummary (Target (TargetModule modl) maybe_buf)
1165 = do maybe_summary <- summarise hsc_env emptyNodeMap Nothing False
1166 modl maybe_buf excl_mods
1167 case maybe_summary of
1168 Nothing -> packageModErr modl
1171 -- In a root module, the filename is allowed to diverge from the module
1172 -- name, so we have to check that there aren't multiple root files
1173 -- defining the same module (otherwise the duplicates will be silently
1174 -- ignored, leading to confusing behaviour).
1175 checkDuplicates :: [ModSummary] -> IO ()
1176 checkDuplicates summaries = mapM_ check summaries
1181 many -> multiRootsErr modl many
1182 where modl = ms_mod summ
1184 [ expectJust "checkDup" (ml_hs_file (ms_location summ'))
1185 | summ' <- summaries, ms_mod summ' == modl ]
1187 loop :: [(FilePath,Module,IsBootInterface)]
1188 -- Work list: process these modules
1189 -> NodeMap ModSummary
1192 -- The result includes the worklist, except
1193 -- for those mentioned in the visited set
1194 loop [] done = return (nodeMapElts done)
1195 loop ((cur_path, wanted_mod, is_boot) : ss) done
1196 | key `elemFM` done = loop ss done
1197 | otherwise = do { mb_s <- summarise hsc_env old_summary_map
1198 (Just cur_path) is_boot
1199 wanted_mod Nothing excl_mods
1201 Nothing -> loop ss done
1202 Just s -> loop (msDeps s ++ ss)
1203 (addToFM done key s) }
1205 key = (wanted_mod, if is_boot then HsBootFile else HsSrcFile)
1207 msDeps :: ModSummary -> [(FilePath, -- Importing module
1208 Module, -- Imported module
1209 IsBootInterface)] -- {-# SOURCE #-} import or not
1210 -- (msDeps s) returns the dependencies of the ModSummary s.
1211 -- A wrinkle is that for a {-# SOURCE #-} import we return
1212 -- *both* the hs-boot file
1213 -- *and* the source file
1214 -- as "dependencies". That ensures that the list of all relevant
1215 -- modules always contains B.hs if it contains B.hs-boot.
1216 -- Remember, this pass isn't doing the topological sort. It's
1217 -- just gathering the list of all relevant ModSummaries
1218 msDeps s = concat [ [(f, m, True), (f,m,False)] | m <- ms_srcimps s]
1219 ++ [(f,m,False) | m <- ms_imps s]
1221 f = msHsFilePath s -- Keep the importing module for error reporting
1224 -----------------------------------------------------------------------------
1225 -- Summarising modules
1227 -- We have two types of summarisation:
1229 -- * Summarise a file. This is used for the root module(s) passed to
1230 -- cmLoadModules. The file is read, and used to determine the root
1231 -- module name. The module name may differ from the filename.
1233 -- * Summarise a module. We are given a module name, and must provide
1234 -- a summary. The finder is used to locate the file in which the module
1237 summariseFile :: HscEnv -> FilePath
1238 -> Maybe (StringBuffer,ClockTime)
1240 -- Used for Haskell source only, I think
1241 -- We know the file name, and we know it exists,
1242 -- but we don't necessarily know the module name (might differ)
1243 summariseFile hsc_env file maybe_buf
1244 = do let dflags = hsc_dflags hsc_env
1246 (dflags', hspp_fn, buf)
1247 <- preprocessFile dflags file maybe_buf
1249 (srcimps,the_imps,mod) <- getImports dflags' buf hspp_fn
1251 -- Make a ModLocation for this file
1252 location <- mkHomeModLocation dflags mod file
1254 -- Tell the Finder cache where it is, so that subsequent calls
1255 -- to findModule will find it, even if it's not on any search path
1256 addHomeModuleToFinder hsc_env mod location
1258 src_timestamp <- case maybe_buf of
1259 Just (_,t) -> return t
1260 Nothing -> getModificationTime file
1262 obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
1264 return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
1265 ms_location = location,
1266 ms_hspp_file = Just hspp_fn,
1267 ms_hspp_buf = Just buf,
1268 ms_srcimps = srcimps, ms_imps = the_imps,
1269 ms_hs_date = src_timestamp,
1270 ms_obj_date = obj_timestamp })
1272 -- Summarise a module, and pick up source and timestamp.
1274 -> NodeMap ModSummary -- Map of old summaries
1275 -> Maybe FilePath -- Importing module (for error messages)
1276 -> IsBootInterface -- True <=> a {-# SOURCE #-} import
1277 -> Module -- Imported module to be summarised
1278 -> Maybe (StringBuffer, ClockTime)
1279 -> [Module] -- Modules to exclude
1280 -> IO (Maybe ModSummary) -- Its new summary
1282 summarise hsc_env old_summary_map cur_mod is_boot wanted_mod maybe_buf excl_mods
1283 | wanted_mod `elem` excl_mods
1286 | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
1287 = do -- Find its new timestamp; all the
1288 -- ModSummaries in the old map have valid ml_hs_files
1289 let location = ms_location old_summary
1290 src_fn = expectJust "summarise" (ml_hs_file location)
1292 -- return the cached summary if the source didn't change
1293 src_timestamp <- case maybe_buf of
1294 Just (_,t) -> return t
1295 Nothing -> getModificationTime src_fn
1297 if ms_hs_date old_summary == src_timestamp
1298 then do -- update the object-file timestamp
1299 obj_timestamp <- getObjTimestamp location is_boot
1300 return (Just old_summary{ ms_obj_date = obj_timestamp })
1302 -- source changed: re-summarise
1303 new_summary location src_fn maybe_buf src_timestamp
1306 = do found <- findModule hsc_env wanted_mod True {-explicit-}
1309 | not (isHomePackage pkg) -> return Nothing
1310 -- Drop external-pkg
1311 | isJust (ml_hs_file location) -> just_found location
1313 err -> noModError dflags cur_mod wanted_mod err
1316 dflags = hsc_dflags hsc_env
1318 hsc_src = if is_boot then HsBootFile else HsSrcFile
1320 just_found location = do
1321 -- Adjust location to point to the hs-boot source file,
1322 -- hi file, object file, when is_boot says so
1323 let location' | is_boot = addBootSuffixLocn location
1324 | otherwise = location
1325 src_fn = expectJust "summarise2" (ml_hs_file location')
1327 -- Check that it exists
1328 -- It might have been deleted since the Finder last found it
1329 maybe_t <- modificationTimeIfExists src_fn
1331 Nothing -> noHsFileErr cur_mod src_fn
1332 Just t -> new_summary location' src_fn Nothing t
1335 new_summary location src_fn maybe_bug src_timestamp
1337 -- Preprocess the source file and get its imports
1338 -- The dflags' contains the OPTIONS pragmas
1339 (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn maybe_buf
1340 (srcimps, the_imps, mod_name) <- getImports dflags' buf hspp_fn
1342 when (mod_name /= wanted_mod) $
1343 throwDyn (ProgramError
1344 (showSDoc (text src_fn
1345 <> text ": file name does not match module name"
1346 <+> quotes (ppr mod_name))))
1348 -- Find the object timestamp, and return the summary
1349 obj_timestamp <- getObjTimestamp location is_boot
1351 return (Just ( ModSummary { ms_mod = wanted_mod,
1352 ms_hsc_src = hsc_src,
1353 ms_location = location,
1354 ms_hspp_file = Just hspp_fn,
1355 ms_hspp_buf = Just buf,
1356 ms_srcimps = srcimps,
1358 ms_hs_date = src_timestamp,
1359 ms_obj_date = obj_timestamp }))
1362 getObjTimestamp location is_boot
1363 = if is_boot then return Nothing
1364 else modificationTimeIfExists (ml_obj_file location)
1367 preprocessFile :: DynFlags -> FilePath -> Maybe (StringBuffer,ClockTime)
1368 -> IO (DynFlags, FilePath, StringBuffer)
1369 preprocessFile dflags src_fn Nothing
1371 (dflags', hspp_fn) <- preprocess dflags src_fn
1372 buf <- hGetStringBuffer hspp_fn
1373 return (dflags', hspp_fn, buf)
1375 preprocessFile dflags src_fn (Just (buf, time))
1377 -- case we bypass the preprocessing stage?
1379 local_opts = getOptionsFromStringBuffer buf
1381 (dflags', errs) <- parseDynamicFlags dflags local_opts
1385 | Unlit _ <- startPhase src_fn = True
1386 -- note: local_opts is only required if there's no Unlit phase
1387 | dopt Opt_Cpp dflags' = True
1388 | dopt Opt_Pp dflags' = True
1391 when needs_preprocessing $
1392 ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
1394 return (dflags', "<buffer>", buf)
1397 -----------------------------------------------------------------------------
1399 -----------------------------------------------------------------------------
1401 noModError :: DynFlags -> Maybe FilePath -> Module -> FindResult -> IO ab
1402 -- ToDo: we don't have a proper line number for this error
1403 noModError dflags cur_mod wanted_mod err
1404 = throwDyn $ ProgramError $ showSDoc $
1405 vcat [cantFindError dflags wanted_mod err,
1406 nest 2 (parens (pp_where cur_mod))]
1408 noHsFileErr cur_mod path
1409 = throwDyn $ CmdLineError $ showSDoc $
1410 vcat [text "Can't find" <+> text path,
1411 nest 2 (parens (pp_where cur_mod))]
1413 pp_where Nothing = text "one of the roots of the dependency analysis"
1414 pp_where (Just p) = text "imported from" <+> text p
1417 = throwDyn (CmdLineError (showSDoc (text "module" <+>
1418 quotes (ppr mod) <+>
1419 text "is a package module")))
1421 multiRootsErr mod files
1422 = throwDyn (ProgramError (showSDoc (
1423 text "module" <+> quotes (ppr mod) <+>
1424 text "is defined in multiple files:" <+>
1425 sep (map text files))))
1427 cyclicModuleErr :: [ModSummary] -> SDoc
1429 = hang (ptext SLIT("Module imports form a cycle for modules:"))
1430 2 (vcat (map show_one ms))
1432 show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
1433 nest 2 $ ptext SLIT("imports:") <+>
1434 (pp_imps HsBootFile (ms_srcimps ms)
1435 $$ pp_imps HsSrcFile (ms_imps ms))]
1436 show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
1437 pp_imps src mods = fsep (map (show_mod src) mods)
1440 -- | Inform GHC that the working directory has changed. GHC will flush
1441 -- its cache of module locations, since it may no longer be valid.
1442 -- Note: if you change the working directory, you should also unload
1443 -- the current program (set targets to empty, followed by load).
1444 workingDirectoryChanged :: Session -> IO ()
1445 workingDirectoryChanged s = withSession s $ \hsc_env ->
1446 flushFinderCache (hsc_FC hsc_env)
1448 -- -----------------------------------------------------------------------------
1449 -- inspecting the session
1451 -- | Get the module dependency graph.
1452 getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
1453 getModuleGraph s = withSession s (return . hsc_mod_graph)
1455 isLoaded :: Session -> Module -> IO Bool
1456 isLoaded s m = withSession s $ \hsc_env ->
1457 return $! isJust (lookupModuleEnv (hsc_HPT hsc_env) m)
1459 getBindings :: Session -> IO [TyThing]
1460 getBindings s = withSession s (return . nameEnvElts . ic_type_env . hsc_IC)
1462 getPrintUnqual :: Session -> IO PrintUnqualified
1463 getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
1466 -- | Parses a string as an identifier, and returns the list of 'Name's that
1467 -- the identifier can refer to in the current interactive context.
1468 parseName :: Session -> String -> IO [Name]
1469 parseName s str = withSession s $ \hsc_env -> do
1470 maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
1471 case maybe_rdr_name of
1472 Nothing -> return []
1473 Just (L _ rdr_name) -> do
1474 mb_names <- tcRnLookupRdrName hsc_env rdr_name
1476 Nothing -> return []
1477 Just ns -> return ns
1478 -- ToDo: should return error messages
1481 -- | Returns the 'TyThing' for a 'Name'. The 'Name' may refer to any
1482 -- entity known to GHC, including 'Name's defined using 'runStmt'.
1483 lookupName :: Session -> Name -> IO (Maybe TyThing)
1484 lookupName s name = withSession s $ \hsc_env -> do
1485 case lookupTypeEnv (ic_type_env (hsc_IC hsc_env)) name of
1486 Just tt -> return (Just tt)
1488 eps <- readIORef (hsc_EPS hsc_env)
1489 return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
1491 -- | Container for information about a 'Module'.
1492 data ModuleInfo = ModuleInfo {
1493 minf_details :: ModDetails,
1494 minf_rdr_env :: Maybe GlobalRdrEnv
1496 -- ToDo: this should really contain the ModIface too
1497 -- We don't want HomeModInfo here, because a ModuleInfo applies
1498 -- to package modules too.
1500 -- | Request information about a loaded 'Module'
1501 getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
1502 getModuleInfo s mdl = withSession s $ \hsc_env -> do
1503 case lookupModuleEnv (hsc_HPT hsc_env) mdl of
1504 Nothing -> return Nothing
1506 return (Just (ModuleInfo {
1507 minf_details = hm_details hmi,
1508 minf_rdr_env = mi_globals $! hm_iface hmi
1511 -- ToDo: we should be able to call getModuleInfo on a package module,
1512 -- even one that isn't loaded yet.
1514 -- | The list of top-level entities defined in a module
1515 modInfoTyThings :: ModuleInfo -> [TyThing]
1516 modInfoTyThings minf = typeEnvElts (md_types (minf_details minf))
1518 modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
1519 modInfoTopLevelScope minf
1520 = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
1522 modInfoExports :: ModuleInfo -> [Name]
1523 modInfoExports minf = nameSetToList $! (md_exports $! minf_details minf)
1525 isDictonaryId :: Id -> Bool
1527 = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
1533 | BinaryCode FilePath
1535 type TypecheckedCode = HsTypecheckedGroup
1536 type RenamedCode = [HsGroup Name]
1538 -- ToDo: typechecks abstract syntax or renamed abstract syntax. Issues:
1539 -- - typechecked syntax includes extra dictionary translation and
1540 -- AbsBinds which need to be translated back into something closer to
1541 -- the original source.
1542 -- - renamed syntax currently doesn't exist in a single blob, since
1543 -- renaming and typechecking are interleaved at splice points. We'd
1544 -- need a restriction that there are no splices in the source module.
1547 -- - Data and Typeable instances for HsSyn.
1550 -- - things that aren't in the output of the renamer:
1551 -- - the export list
1555 -- - things that aren't in the output of the typechecker right now:
1556 -- - the export list
1558 -- - type signatures
1559 -- - type/data/newtype declarations
1560 -- - class declarations
1562 -- - extra things in the typechecker's output:
1563 -- - default methods are turned into top-level decls.
1564 -- - dictionary bindings
1566 -- ToDo: check for small transformations that happen to the syntax in
1567 -- the typechecker (eg. -e ==> negate e, perhaps for fromIntegral)
1569 -- ToDo: maybe use TH syntax instead of IfaceSyn? There's already a way
1570 -- to get from TyCons, Ids etc. to TH syntax (reify).
1572 -- :browse will use either lm_toplev or inspect lm_interface, depending
1573 -- on whether the module is interpreted or not.
1575 -- various abstract syntax types (perhaps IfaceBlah)
1579 -- This is for reconstructing refactored source code
1580 -- Calls the lexer repeatedly.
1581 -- ToDo: add comment tokens to token stream
1582 getTokenStream :: Session -> Module -> IO [Located Token]
1585 -- -----------------------------------------------------------------------------
1586 -- Interactive evaluation
1590 -- | Set the interactive evaluation context.
1592 -- Setting the context doesn't throw away any bindings; the bindings
1593 -- we've built up in the InteractiveContext simply move to the new
1594 -- module. They always shadow anything in scope in the current context.
1595 setContext :: Session
1596 -> [Module] -- entire top level scope of these modules
1597 -> [Module] -- exports only of these modules
1599 setContext (Session ref) toplevs exports = do
1600 hsc_env <- readIORef ref
1601 let old_ic = hsc_IC hsc_env
1602 hpt = hsc_HPT hsc_env
1604 mapM_ (checkModuleExists hsc_env hpt) exports
1605 export_env <- mkExportEnv hsc_env exports
1606 toplev_envs <- mapM (mkTopLevEnv hpt) toplevs
1607 let all_env = foldr plusGlobalRdrEnv export_env toplev_envs
1608 writeIORef ref hsc_env{ hsc_IC = old_ic { ic_toplev_scope = toplevs,
1609 ic_exports = exports,
1610 ic_rn_gbl_env = all_env } }
1612 checkModuleExists :: HscEnv -> HomePackageTable -> Module -> IO ()
1613 checkModuleExists hsc_env hpt mod =
1614 case lookupModuleEnv hpt mod of
1615 Just mod_info -> return ()
1616 _not_a_home_module -> do
1617 res <- findPackageModule hsc_env mod True
1619 Found _ _ -> return ()
1620 err -> let msg = cantFindError (hsc_dflags hsc_env) mod err in
1621 throwDyn (CmdLineError (showSDoc msg))
1623 mkTopLevEnv :: HomePackageTable -> Module -> IO GlobalRdrEnv
1624 mkTopLevEnv hpt modl
1625 = case lookupModuleEnv hpt modl of
1627 throwDyn (ProgramError ("mkTopLevEnv: not a home module "
1628 ++ showSDoc (pprModule modl)))
1630 case mi_globals (hm_iface details) of
1632 throwDyn (ProgramError ("mkTopLevEnv: not interpreted "
1633 ++ showSDoc (pprModule modl)))
1634 Just env -> return env
1636 -- | Get the interactive evaluation context, consisting of a pair of the
1637 -- set of modules from which we take the full top-level scope, and the set
1638 -- of modules from which we take just the exports respectively.
1639 getContext :: Session -> IO ([Module],[Module])
1640 getContext s = withSession s (\HscEnv{ hsc_IC=ic } ->
1641 return (ic_toplev_scope ic, ic_exports ic))
1643 -- | Returns 'True' if the specified module is interpreted, and hence has
1644 -- its full top-level scope available.
1645 moduleIsInterpreted :: Session -> Module -> IO Bool
1646 moduleIsInterpreted s modl = withSession s $ \h ->
1647 case lookupModuleEnv (hsc_HPT h) modl of
1648 Just details -> return (isJust (mi_globals (hm_iface details)))
1649 _not_a_home_module -> return False
1651 -- | Looks up an identifier in the current interactive context (for :info)
1652 {-# DEPRECATED getInfo "we should be using parseName/lookupName instead" #-}
1653 getInfo :: Session -> String -> IO [GetInfoResult]
1654 getInfo s id = withSession s $ \hsc_env -> hscGetInfo hsc_env id
1656 -- | Returns all names in scope in the current interactive context
1657 getNamesInScope :: Session -> IO [Name]
1658 getNamesInScope s = withSession s $ \hsc_env -> do
1659 return (map gre_name (globalRdrEnvElts (ic_rn_gbl_env (hsc_IC hsc_env))))
1661 -- -----------------------------------------------------------------------------
1662 -- Getting the type of an expression
1664 -- | Get the type of an expression
1665 exprType :: Session -> String -> IO (Maybe Type)
1666 exprType s expr = withSession s $ \hsc_env -> do
1667 maybe_stuff <- hscTcExpr hsc_env expr
1669 Nothing -> return Nothing
1670 Just ty -> return (Just tidy_ty)
1672 tidy_ty = tidyType emptyTidyEnv ty
1673 dflags = hsc_dflags hsc_env
1675 -- -----------------------------------------------------------------------------
1676 -- Getting the kind of a type
1678 -- | Get the kind of a type
1679 typeKind :: Session -> String -> IO (Maybe Kind)
1680 typeKind s str = withSession s $ \hsc_env -> do
1681 maybe_stuff <- hscKcType hsc_env str
1683 Nothing -> return Nothing
1684 Just kind -> return (Just kind)
1686 -----------------------------------------------------------------------------
1687 -- cmCompileExpr: compile an expression and deliver an HValue
1689 compileExpr :: Session -> String -> IO (Maybe HValue)
1690 compileExpr s expr = withSession s $ \hsc_env -> do
1691 maybe_stuff <- hscStmt hsc_env ("let __cmCompileExpr = "++expr)
1693 Nothing -> return Nothing
1694 Just (new_ic, names, hval) -> do
1696 hvals <- (unsafeCoerce# hval) :: IO [HValue]
1698 case (names,hvals) of
1699 ([n],[hv]) -> return (Just hv)
1700 _ -> panic "compileExpr"
1702 -- -----------------------------------------------------------------------------
1703 -- running a statement interactively
1706 = RunOk [Name] -- ^ names bound by this evaluation
1707 | RunFailed -- ^ statement failed compilation
1708 | RunException Exception -- ^ statement raised an exception
1710 -- | Run a statement in the current interactive context. Statemenet
1711 -- may bind multple values.
1712 runStmt :: Session -> String -> IO RunResult
1713 runStmt (Session ref) expr
1715 hsc_env <- readIORef ref
1717 -- Turn off -fwarn-unused-bindings when running a statement, to hide
1718 -- warnings about the implicit bindings we introduce.
1719 let dflags' = dopt_unset (hsc_dflags hsc_env) Opt_WarnUnusedBinds
1720 hsc_env' = hsc_env{ hsc_dflags = dflags' }
1722 maybe_stuff <- hscStmt hsc_env' expr
1725 Nothing -> return RunFailed
1726 Just (new_hsc_env, names, hval) -> do
1728 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
1729 either_hvals <- sandboxIO thing_to_run
1731 case either_hvals of
1733 -- on error, keep the *old* interactive context,
1734 -- so that 'it' is not bound to something
1735 -- that doesn't exist.
1736 return (RunException e)
1739 -- Get the newly bound things, and bind them.
1740 -- Don't need to delete any shadowed bindings;
1741 -- the new ones override the old ones.
1742 extendLinkEnv (zip names hvals)
1744 writeIORef ref new_hsc_env
1745 return (RunOk names)
1748 -- We run the statement in a "sandbox" to protect the rest of the
1749 -- system from anything the expression might do. For now, this
1750 -- consists of just wrapping it in an exception handler, but see below
1751 -- for another version.
1753 sandboxIO :: IO a -> IO (Either Exception a)
1754 sandboxIO thing = Exception.try thing
1757 -- This version of sandboxIO runs the expression in a completely new
1758 -- RTS main thread. It is disabled for now because ^C exceptions
1759 -- won't be delivered to the new thread, instead they'll be delivered
1760 -- to the (blocked) GHCi main thread.
1762 -- SLPJ: when re-enabling this, reflect a wrong-stat error as an exception
1764 sandboxIO :: IO a -> IO (Either Int (Either Exception a))
1765 sandboxIO thing = do
1766 st_thing <- newStablePtr (Exception.try thing)
1767 alloca $ \ p_st_result -> do
1768 stat <- rts_evalStableIO st_thing p_st_result
1769 freeStablePtr st_thing
1771 then do st_result <- peek p_st_result
1772 result <- deRefStablePtr st_result
1773 freeStablePtr st_result
1774 return (Right result)
1776 return (Left (fromIntegral stat))
1778 foreign import "rts_evalStableIO" {- safe -}
1779 rts_evalStableIO :: StablePtr (IO a) -> Ptr (StablePtr a) -> IO CInt
1780 -- more informative than the C type!
1783 -- ---------------------------------------------------------------------------
1784 -- cmBrowseModule: get all the TyThings defined in a module
1786 {-# DEPRECATED browseModule "we should be using getModuleInfo instead" #-}
1787 browseModule :: Session -> Module -> Bool -> IO [IfaceDecl]
1788 browseModule s modl exports_only = withSession s $ \hsc_env -> do
1789 mb_decls <- getModuleContents hsc_env modl exports_only
1791 Nothing -> return [] -- An error of some kind
1792 Just ds -> return ds
1795 -----------------------------------------------------------------------------
1796 -- show a module and it's source/object filenames
1798 showModule :: Session -> ModSummary -> IO String
1799 showModule s mod_summary = withSession s $ \hsc_env -> do
1800 case lookupModuleEnv (hsc_HPT hsc_env) (ms_mod mod_summary) of
1801 Nothing -> panic "missing linkable"
1802 Just mod_info -> return (showModMsg obj_linkable mod_summary)
1804 obj_linkable = isObjectLinkable (fromJust (hm_linkable mod_info))