+
+-- | This is the way to get access to parsed and typechecked source code
+-- for a module. 'checkModule' loads all the dependencies of the specified
+-- module in the Session, and then attempts to typecheck the module. If
+-- successful, it returns the abstract syntax for the module.
+checkModule :: Session -> Module -> IO (Maybe CheckedModule)
+checkModule session@(Session ref) mod = do
+ -- load up the dependencies first
+ r <- load session (LoadDependenciesOf mod)
+ if (failed r) then return Nothing else do
+
+ -- now parse & typecheck the module
+ hsc_env <- readIORef ref
+ let mg = hsc_mod_graph hsc_env
+ case [ ms | ms <- mg, ms_mod ms == mod ] of
+ [] -> return Nothing
+ (ms:_) -> do
+ -- Add in the OPTIONS from the source file This is nasty:
+ -- we've done this once already, in the compilation manager
+ -- It might be better to cache the flags in the
+ -- ml_hspp_file field, say
+ let dflags0 = hsc_dflags hsc_env
+ hspp_buf = expectJust "GHC.checkModule" (ms_hspp_buf ms)
+ filename = fromJust (ml_hs_file (ms_location ms))
+ opts = getOptionsFromStringBuffer hspp_buf filename
+ (dflags1,leftovers) <- parseDynamicFlags dflags0 (map snd opts)
+ if (not (null leftovers))
+ then do printErrorsAndWarnings dflags1 (optionsErrorMsgs leftovers opts filename)
+ return Nothing
+ else do
+
+ r <- hscFileCheck hsc_env{hsc_dflags=dflags1} ms
+ case r of
+ HscFail ->
+ return Nothing
+ HscChecked parsed renamed Nothing ->
+ return (Just (CheckedModule {
+ parsedSource = parsed,
+ renamedSource = renamed,
+ typecheckedSource = Nothing,
+ checkedModuleInfo = Nothing }))
+ HscChecked parsed renamed
+ (Just (tc_binds, rdr_env, details)) -> do
+ let minf = ModuleInfo {
+ minf_type_env = md_types details,
+ minf_exports = md_exports details,
+ minf_rdr_env = Just rdr_env,
+ minf_instances = md_insts details
+ }
+ return (Just (CheckedModule {
+ parsedSource = parsed,
+ renamedSource = renamed,
+ typecheckedSource = Just tc_binds,
+ checkedModuleInfo = Just minf }))
+ _other ->
+ panic "checkModule"
+
+-- ---------------------------------------------------------------------------
+-- Unloading
+
+unload :: HscEnv -> [Linkable] -> IO ()
+unload hsc_env stable_linkables -- Unload everthing *except* 'stable_linkables'
+ = case ghcMode (hsc_dflags hsc_env) of
+ BatchCompile -> return ()
+ JustTypecheck -> return ()
+#ifdef GHCI
+ Interactive -> Linker.unload (hsc_dflags hsc_env) stable_linkables
+#else
+ Interactive -> panic "unload: no interpreter"
+#endif
+ other -> panic "unload: strange mode"
+
+-- -----------------------------------------------------------------------------
+-- checkStability
+
+{-
+ Stability tells us which modules definitely do not need to be recompiled.
+ There are two main reasons for having stability:
+
+ - avoid doing a complete upsweep of the module graph in GHCi when
+ modules near the bottom of the tree have not changed.
+
+ - to tell GHCi when it can load object code: we can only load object code
+ for a module when we also load object code fo all of the imports of the
+ module. So we need to know that we will definitely not be recompiling
+ any of these modules, and we can use the object code.
+
+ NB. stability is of no importance to BatchCompile at all, only Interactive.
+ (ToDo: what about JustTypecheck?)
+
+ The stability check is as follows. Both stableObject and
+ stableBCO are used during the upsweep phase later.
+
+ -------------------
+ stable m = stableObject m || stableBCO m
+
+ stableObject m =
+ all stableObject (imports m)
+ && old linkable does not exist, or is == on-disk .o
+ && date(on-disk .o) > date(.hs)
+
+ stableBCO m =
+ all stable (imports m)
+ && date(BCO) > date(.hs)
+ -------------------
+
+ These properties embody the following ideas:
+
+ - if a module is stable:
+ - if it has been compiled in a previous pass (present in HPT)
+ then it does not need to be compiled or re-linked.
+ - if it has not been compiled in a previous pass,
+ then we only need to read its .hi file from disk and
+ link it to produce a ModDetails.
+
+ - if a modules is not stable, we will definitely be at least
+ re-linking, and possibly re-compiling it during the upsweep.
+ All non-stable modules can (and should) therefore be unlinked
+ before the upsweep.
+
+ - Note that objects are only considered stable if they only depend
+ on other objects. We can't link object code against byte code.
+-}
+
+checkStability
+ :: HomePackageTable -- HPT from last compilation
+ -> [SCC ModSummary] -- current module graph (cyclic)
+ -> [Module] -- all home modules
+ -> ([Module], -- stableObject
+ [Module]) -- stableBCO
+
+checkStability hpt sccs all_home_mods = foldl checkSCC ([],[]) sccs
+ where
+ checkSCC (stable_obj, stable_bco) scc0
+ | stableObjects = (scc_mods ++ stable_obj, stable_bco)
+ | stableBCOs = (stable_obj, scc_mods ++ stable_bco)
+ | otherwise = (stable_obj, stable_bco)
+ where
+ scc = flattenSCC scc0
+ scc_mods = map ms_mod scc
+ home_module m = m `elem` all_home_mods && m `notElem` scc_mods
+
+ scc_allimps = nub (filter home_module (concatMap ms_allimps scc))
+ -- all imports outside the current SCC, but in the home pkg
+
+ stable_obj_imps = map (`elem` stable_obj) scc_allimps
+ stable_bco_imps = map (`elem` stable_bco) scc_allimps
+
+ stableObjects =
+ and stable_obj_imps
+ && all object_ok scc
+
+ stableBCOs =
+ and (zipWith (||) stable_obj_imps stable_bco_imps)
+ && all bco_ok scc
+
+ object_ok ms
+ | Just t <- ms_obj_date ms = t >= ms_hs_date ms
+ && same_as_prev t
+ | otherwise = False
+ where
+ same_as_prev t = case lookupModuleEnv hpt (ms_mod ms) of
+ Just hmi | Just l <- hm_linkable hmi
+ -> isObjectLinkable l && t == linkableTime l
+ _other -> True
+ -- why '>=' rather than '>' above? If the filesystem stores
+ -- times to the nearset second, we may occasionally find that
+ -- the object & source have the same modification time,
+ -- especially if the source was automatically generated
+ -- and compiled. Using >= is slightly unsafe, but it matches
+ -- make's behaviour.
+
+ bco_ok ms
+ = case lookupModuleEnv hpt (ms_mod ms) of
+ Just hmi | Just l <- hm_linkable hmi ->
+ not (isObjectLinkable l) &&
+ linkableTime l >= ms_hs_date ms
+ _other -> False
+
+ms_allimps :: ModSummary -> [Module]
+ms_allimps ms = map unLoc (ms_srcimps ms ++ ms_imps ms)
+
+-- -----------------------------------------------------------------------------
+-- Prune the HomePackageTable
+
+-- Before doing an upsweep, we can throw away:
+--
+-- - For non-stable modules:
+-- - all ModDetails, all linked code
+-- - all unlinked code that is out of date with respect to
+-- the source file
+--
+-- This is VERY IMPORTANT otherwise we'll end up requiring 2x the
+-- space at the end of the upsweep, because the topmost ModDetails of the
+-- old HPT holds on to the entire type environment from the previous
+-- compilation.
+
+pruneHomePackageTable
+ :: HomePackageTable
+ -> [ModSummary]
+ -> ([Module],[Module])
+ -> HomePackageTable
+
+pruneHomePackageTable hpt summ (stable_obj, stable_bco)
+ = mapModuleEnv prune hpt
+ where prune hmi
+ | is_stable modl = hmi'
+ | otherwise = hmi'{ hm_details = emptyModDetails }
+ where
+ modl = mi_module (hm_iface hmi)
+ hmi' | Just l <- hm_linkable hmi, linkableTime l < ms_hs_date ms
+ = hmi{ hm_linkable = Nothing }
+ | otherwise
+ = hmi
+ where ms = expectJust "prune" (lookupModuleEnv ms_map modl)
+
+ ms_map = mkModuleEnv [(ms_mod ms, ms) | ms <- summ]
+
+ is_stable m = m `elem` stable_obj || m `elem` stable_bco
+
+-- -----------------------------------------------------------------------------
+
+-- Return (names of) all those in modsDone who are part of a cycle
+-- as defined by theGraph.
+findPartiallyCompletedCycles :: [Module] -> [SCC ModSummary] -> [Module]
+findPartiallyCompletedCycles modsDone theGraph
+ = chew theGraph
+ where
+ chew [] = []
+ chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
+ chew ((CyclicSCC vs):rest)
+ = let names_in_this_cycle = nub (map ms_mod vs)
+ mods_in_this_cycle
+ = nub ([done | done <- modsDone,
+ done `elem` names_in_this_cycle])
+ chewed_rest = chew rest
+ in
+ if notNull mods_in_this_cycle
+ && length mods_in_this_cycle < length names_in_this_cycle
+ then mods_in_this_cycle ++ chewed_rest
+ else chewed_rest
+
+-- -----------------------------------------------------------------------------
+-- The upsweep
+
+-- This is where we compile each module in the module graph, in a pass
+-- from the bottom to the top of the graph.
+
+-- There better had not be any cyclic groups here -- we check for them.
+
+upsweep
+ :: HscEnv -- Includes initially-empty HPT
+ -> HomePackageTable -- HPT from last time round (pruned)
+ -> ([Module],[Module]) -- stable modules (see checkStability)
+ -> IO () -- How to clean up unwanted tmp files
+ -> [SCC ModSummary] -- Mods to do (the worklist)
+ -> IO (SuccessFlag,
+ HscEnv, -- With an updated HPT
+ [ModSummary]) -- Mods which succeeded
+
+upsweep hsc_env old_hpt stable_mods cleanup mods
+ = upsweep' hsc_env old_hpt stable_mods cleanup mods 1 (length mods)
+
+upsweep' hsc_env old_hpt stable_mods cleanup
+ [] _ _
+ = return (Succeeded, hsc_env, [])
+
+upsweep' hsc_env old_hpt stable_mods cleanup
+ (CyclicSCC ms:_) _ _
+ = do fatalErrorMsg (hsc_dflags hsc_env) (cyclicModuleErr ms)
+ return (Failed, hsc_env, [])
+
+upsweep' hsc_env old_hpt stable_mods cleanup
+ (AcyclicSCC mod:mods) mod_index nmods
+ = do -- putStrLn ("UPSWEEP_MOD: hpt = " ++
+ -- show (map (moduleUserString.moduleName.mi_module.hm_iface)
+ -- (moduleEnvElts (hsc_HPT hsc_env)))
+
+ mb_mod_info <- upsweep_mod hsc_env old_hpt stable_mods mod
+ mod_index nmods
+
+ cleanup -- Remove unwanted tmp files between compilations
+
+ case mb_mod_info of
+ Nothing -> return (Failed, hsc_env, [])
+ Just mod_info -> do
+ { let this_mod = ms_mod mod
+
+ -- Add new info to hsc_env
+ hpt1 = extendModuleEnv (hsc_HPT hsc_env)
+ this_mod mod_info
+ hsc_env1 = hsc_env { hsc_HPT = hpt1 }
+
+ -- Space-saving: delete the old HPT entry
+ -- for mod BUT if mod is a hs-boot
+ -- node, don't delete it. For the
+ -- interface, the HPT entry is probaby for the
+ -- main Haskell source file. Deleting it
+ -- would force .. (what?? --SDM)
+ old_hpt1 | isBootSummary mod = old_hpt
+ | otherwise = delModuleEnv old_hpt this_mod
+
+ ; (restOK, hsc_env2, modOKs)
+ <- upsweep' hsc_env1 old_hpt1 stable_mods cleanup
+ mods (mod_index+1) nmods
+ ; return (restOK, hsc_env2, mod:modOKs)
+ }
+
+
+-- Compile a single module. Always produce a Linkable for it if
+-- successful. If no compilation happened, return the old Linkable.
+upsweep_mod :: HscEnv
+ -> HomePackageTable
+ -> ([Module],[Module])
+ -> ModSummary
+ -> Int -- index of module
+ -> Int -- total number of modules
+ -> IO (Maybe HomeModInfo) -- Nothing => Failed
+
+upsweep_mod hsc_env old_hpt (stable_obj, stable_bco) summary mod_index nmods
+ = do
+ let
+ this_mod = ms_mod summary
+ mb_obj_date = ms_obj_date summary
+ obj_fn = ml_obj_file (ms_location summary)
+ hs_date = ms_hs_date summary
+
+ compile_it :: Maybe Linkable -> IO (Maybe HomeModInfo)
+ compile_it = upsweep_compile hsc_env old_hpt this_mod
+ summary mod_index nmods
+
+ case ghcMode (hsc_dflags hsc_env) of
+ BatchCompile ->
+ case () of
+ -- Batch-compilating is easy: just check whether we have
+ -- an up-to-date object file. If we do, then the compiler
+ -- needs to do a recompilation check.
+ _ | Just obj_date <- mb_obj_date, obj_date >= hs_date -> do
+ linkable <-
+ findObjectLinkable this_mod obj_fn obj_date
+ compile_it (Just linkable)
+
+ | otherwise ->
+ compile_it Nothing
+
+ interactive ->
+ case () of
+ _ | is_stable_obj, isJust old_hmi ->
+ return old_hmi
+ -- object is stable, and we have an entry in the
+ -- old HPT: nothing to do
+
+ | is_stable_obj, isNothing old_hmi -> do
+ linkable <-
+ findObjectLinkable this_mod obj_fn
+ (expectJust "upseep1" mb_obj_date)
+ compile_it (Just linkable)
+ -- object is stable, but we need to load the interface
+ -- off disk to make a HMI.
+
+ | is_stable_bco ->
+ ASSERT(isJust old_hmi) -- must be in the old_hpt
+ return old_hmi
+ -- BCO is stable: nothing to do
+
+ | Just hmi <- old_hmi,
+ Just l <- hm_linkable hmi, not (isObjectLinkable l),
+ linkableTime l >= ms_hs_date summary ->
+ compile_it (Just l)
+ -- we have an old BCO that is up to date with respect
+ -- to the source: do a recompilation check as normal.
+
+ | otherwise ->
+ compile_it Nothing
+ -- no existing code at all: we must recompile.
+ where
+ is_stable_obj = this_mod `elem` stable_obj
+ is_stable_bco = this_mod `elem` stable_bco
+
+ old_hmi = lookupModuleEnv old_hpt this_mod
+
+-- Run hsc to compile a module
+upsweep_compile hsc_env old_hpt this_mod summary
+ mod_index nmods
+ mb_old_linkable = do
+ let
+ -- The old interface is ok if it's in the old HPT
+ -- a) we're compiling a source file, and the old HPT
+ -- entry is for a source file
+ -- b) we're compiling a hs-boot file
+ -- Case (b) allows an hs-boot file to get the interface of its
+ -- real source file on the second iteration of the compilation
+ -- manager, but that does no harm. Otherwise the hs-boot file
+ -- will always be recompiled
+
+ mb_old_iface
+ = case lookupModuleEnv old_hpt this_mod of
+ Nothing -> Nothing
+ Just hm_info | isBootSummary summary -> Just iface
+ | not (mi_boot iface) -> Just iface
+ | otherwise -> Nothing
+ where
+ iface = hm_iface hm_info
+
+ compresult <- compile hsc_env summary mb_old_linkable mb_old_iface
+ mod_index nmods
+
+ case compresult of
+ -- Compilation failed. Compile may still have updated the PCS, tho.
+ CompErrs -> return Nothing
+
+ -- Compilation "succeeded", and may or may not have returned a new
+ -- linkable (depending on whether compilation was actually performed
+ -- or not).
+ CompOK new_details new_iface new_linkable
+ -> do let new_info = HomeModInfo { hm_iface = new_iface,
+ hm_details = new_details,
+ hm_linkable = new_linkable }
+ return (Just new_info)
+
+
+-- Filter modules in the HPT
+retainInTopLevelEnvs :: [Module] -> HomePackageTable -> HomePackageTable
+retainInTopLevelEnvs keep_these hpt
+ = mkModuleEnv [ (mod, expectJust "retain" mb_mod_info)
+ | mod <- keep_these
+ , let mb_mod_info = lookupModuleEnv hpt mod
+ , isJust mb_mod_info ]
+
+-- ---------------------------------------------------------------------------
+-- Topological sort of the module graph
+
+topSortModuleGraph
+ :: Bool -- Drop hi-boot nodes? (see below)
+ -> [ModSummary]
+ -> Maybe Module
+ -> [SCC ModSummary]
+-- Calculate SCCs of the module graph, possibly dropping the hi-boot nodes
+-- The resulting list of strongly-connected-components is in topologically
+-- sorted order, starting with the module(s) at the bottom of the
+-- dependency graph (ie compile them first) and ending with the ones at
+-- the top.
+--
+-- Drop hi-boot nodes (first boolean arg)?
+--
+-- False: treat the hi-boot summaries as nodes of the graph,
+-- so the graph must be acyclic
+--
+-- True: eliminate the hi-boot nodes, and instead pretend
+-- the a source-import of Foo is an import of Foo
+-- The resulting graph has no hi-boot nodes, but can by cyclic
+
+topSortModuleGraph drop_hs_boot_nodes summaries Nothing
+ = stronglyConnComp (fst (moduleGraphNodes drop_hs_boot_nodes summaries))
+topSortModuleGraph drop_hs_boot_nodes summaries (Just mod)
+ = stronglyConnComp (map vertex_fn (reachable graph root))
+ where
+ -- restrict the graph to just those modules reachable from
+ -- the specified module. We do this by building a graph with
+ -- the full set of nodes, and determining the reachable set from
+ -- the specified node.
+ (nodes, lookup_key) = moduleGraphNodes drop_hs_boot_nodes summaries
+ (graph, vertex_fn, key_fn) = graphFromEdges' nodes
+ root
+ | Just key <- lookup_key HsSrcFile mod, Just v <- key_fn key = v
+ | otherwise = throwDyn (ProgramError "module does not exist")
+
+moduleGraphNodes :: Bool -> [ModSummary]
+ -> ([(ModSummary, Int, [Int])], HscSource -> Module -> Maybe Int)
+moduleGraphNodes drop_hs_boot_nodes summaries = (nodes, lookup_key)
+ where
+ -- Drop hs-boot nodes by using HsSrcFile as the key
+ hs_boot_key | drop_hs_boot_nodes = HsSrcFile
+ | otherwise = HsBootFile
+
+ -- We use integers as the keys for the SCC algorithm
+ nodes :: [(ModSummary, Int, [Int])]
+ nodes = [(s, expectJust "topSort" (lookup_key (ms_hsc_src s) (ms_mod s)),
+ out_edge_keys hs_boot_key (map unLoc (ms_srcimps s)) ++
+ out_edge_keys HsSrcFile (map unLoc (ms_imps s)) )
+ | s <- summaries
+ , not (isBootSummary s && drop_hs_boot_nodes) ]
+ -- Drop the hi-boot ones if told to do so
+
+ key_map :: NodeMap Int
+ key_map = listToFM ([(ms_mod s, ms_hsc_src s) | s <- summaries]
+ `zip` [1..])
+
+ lookup_key :: HscSource -> Module -> Maybe Int
+ lookup_key hs_src mod = lookupFM key_map (mod, hs_src)
+
+ out_edge_keys :: HscSource -> [Module] -> [Int]
+ out_edge_keys hi_boot ms = mapCatMaybes (lookup_key hi_boot) ms
+ -- If we want keep_hi_boot_nodes, then we do lookup_key with
+ -- the IsBootInterface parameter True; else False
+
+
+type NodeKey = (Module, HscSource) -- The nodes of the graph are
+type NodeMap a = FiniteMap NodeKey a -- keyed by (mod, src_file_type) pairs
+
+msKey :: ModSummary -> NodeKey
+msKey (ModSummary { ms_mod = mod, ms_hsc_src = boot }) = (mod,boot)
+
+mkNodeMap :: [ModSummary] -> NodeMap ModSummary
+mkNodeMap summaries = listToFM [ (msKey s, s) | s <- summaries]
+
+nodeMapElts :: NodeMap a -> [a]
+nodeMapElts = eltsFM
+
+-----------------------------------------------------------------------------
+-- Downsweep (dependency analysis)
+
+-- Chase downwards from the specified root set, returning summaries
+-- for all home modules encountered. Only follow source-import
+-- links.
+
+-- We pass in the previous collection of summaries, which is used as a
+-- cache to avoid recalculating a module summary if the source is
+-- unchanged.
+--
+-- The returned list of [ModSummary] nodes has one node for each home-package
+-- module, plus one for any hs-boot files. The imports of these nodes
+-- are all there, including the imports of non-home-package modules.
+
+downsweep :: HscEnv
+ -> [ModSummary] -- Old summaries
+ -> [Module] -- Ignore dependencies on these; treat
+ -- them as if they were package modules
+ -> Bool -- True <=> allow multiple targets to have
+ -- the same module name; this is
+ -- very useful for ghc -M
+ -> IO (Maybe [ModSummary])
+ -- The elts of [ModSummary] all have distinct
+ -- (Modules, IsBoot) identifiers, unless the Bool is true
+ -- in which case there can be repeats
+downsweep hsc_env old_summaries excl_mods allow_dup_roots
+ = -- catch error messages and return them
+ handleDyn (\err_msg -> printBagOfErrors (hsc_dflags hsc_env) (unitBag err_msg) >> return Nothing) $ do
+ rootSummaries <- mapM getRootSummary roots
+ let root_map = mkRootMap rootSummaries
+ checkDuplicates root_map
+ summs <- loop (concatMap msDeps rootSummaries) root_map
+ return (Just summs)
+ where
+ roots = hsc_targets hsc_env
+
+ old_summary_map :: NodeMap ModSummary
+ old_summary_map = mkNodeMap old_summaries
+
+ getRootSummary :: Target -> IO ModSummary
+ getRootSummary (Target (TargetFile file mb_phase) maybe_buf)
+ = do exists <- doesFileExist file
+ if exists
+ then summariseFile hsc_env old_summaries file mb_phase maybe_buf
+ else throwDyn $ mkPlainErrMsg noSrcSpan $
+ text "can't find file:" <+> text file
+ getRootSummary (Target (TargetModule modl) maybe_buf)
+ = do maybe_summary <- summariseModule hsc_env old_summary_map False
+ (L rootLoc modl) maybe_buf excl_mods
+ case maybe_summary of
+ Nothing -> packageModErr modl
+ Just s -> return s
+
+ rootLoc = mkGeneralSrcSpan FSLIT("<command line>")
+
+ -- In a root module, the filename is allowed to diverge from the module
+ -- name, so we have to check that there aren't multiple root files
+ -- defining the same module (otherwise the duplicates will be silently
+ -- ignored, leading to confusing behaviour).
+ checkDuplicates :: NodeMap [ModSummary] -> IO ()
+ checkDuplicates root_map
+ | allow_dup_roots = return ()
+ | null dup_roots = return ()
+ | otherwise = multiRootsErr (head dup_roots)
+ where
+ dup_roots :: [[ModSummary]] -- Each at least of length 2
+ dup_roots = filterOut isSingleton (nodeMapElts root_map)
+
+ loop :: [(Located Module,IsBootInterface)]
+ -- Work list: process these modules
+ -> NodeMap [ModSummary]
+ -- Visited set; the range is a list because
+ -- the roots can have the same module names
+ -- if allow_dup_roots is True
+ -> IO [ModSummary]
+ -- The result includes the worklist, except
+ -- for those mentioned in the visited set
+ loop [] done = return (concat (nodeMapElts done))
+ loop ((wanted_mod, is_boot) : ss) done
+ | Just summs <- lookupFM done key
+ = if isSingleton summs then
+ loop ss done
+ else
+ do { multiRootsErr summs; return [] }
+ | otherwise = do { mb_s <- summariseModule hsc_env old_summary_map
+ is_boot wanted_mod Nothing excl_mods
+ ; case mb_s of
+ Nothing -> loop ss done
+ Just s -> loop (msDeps s ++ ss)
+ (addToFM done key [s]) }
+ where
+ key = (unLoc wanted_mod, if is_boot then HsBootFile else HsSrcFile)
+
+mkRootMap :: [ModSummary] -> NodeMap [ModSummary]
+mkRootMap summaries = addListToFM_C (++) emptyFM
+ [ (msKey s, [s]) | s <- summaries ]
+
+msDeps :: ModSummary -> [(Located Module, IsBootInterface)]
+-- (msDeps s) returns the dependencies of the ModSummary s.
+-- A wrinkle is that for a {-# SOURCE #-} import we return
+-- *both* the hs-boot file
+-- *and* the source file
+-- as "dependencies". That ensures that the list of all relevant
+-- modules always contains B.hs if it contains B.hs-boot.
+-- Remember, this pass isn't doing the topological sort. It's
+-- just gathering the list of all relevant ModSummaries
+msDeps s =
+ concat [ [(m,True), (m,False)] | m <- ms_srcimps s ]
+ ++ [ (m,False) | m <- ms_imps s ]
+
+-----------------------------------------------------------------------------
+-- Summarising modules
+
+-- We have two types of summarisation:
+--
+-- * Summarise a file. This is used for the root module(s) passed to
+-- cmLoadModules. The file is read, and used to determine the root
+-- module name. The module name may differ from the filename.
+--
+-- * Summarise a module. We are given a module name, and must provide
+-- a summary. The finder is used to locate the file in which the module
+-- resides.
+
+summariseFile
+ :: HscEnv
+ -> [ModSummary] -- old summaries
+ -> FilePath -- source file name
+ -> Maybe Phase -- start phase
+ -> Maybe (StringBuffer,ClockTime)
+ -> IO ModSummary
+
+summariseFile hsc_env old_summaries file mb_phase maybe_buf
+ -- we can use a cached summary if one is available and the
+ -- source file hasn't changed, But we have to look up the summary
+ -- by source file, rather than module name as we do in summarise.
+ | Just old_summary <- findSummaryBySourceFile old_summaries file
+ = do
+ let location = ms_location old_summary
+
+ -- return the cached summary if the source didn't change
+ src_timestamp <- case maybe_buf of
+ Just (_,t) -> return t
+ Nothing -> getModificationTime file
+ -- The file exists; we checked in getRootSummary above.
+ -- If it gets removed subsequently, then this
+ -- getModificationTime may fail, but that's the right
+ -- behaviour.
+
+ if ms_hs_date old_summary == src_timestamp
+ then do -- update the object-file timestamp
+ obj_timestamp <- getObjTimestamp location False
+ return old_summary{ ms_obj_date = obj_timestamp }
+ else
+ new_summary
+
+ | otherwise
+ = new_summary
+ where
+ new_summary = do
+ let dflags = hsc_dflags hsc_env
+
+ (dflags', hspp_fn, buf)
+ <- preprocessFile dflags file mb_phase maybe_buf
+
+ (srcimps,the_imps, L _ mod) <- getImports dflags' buf hspp_fn
+
+ -- Make a ModLocation for this file
+ location <- mkHomeModLocation dflags mod file
+
+ -- Tell the Finder cache where it is, so that subsequent calls
+ -- to findModule will find it, even if it's not on any search path
+ addHomeModuleToFinder hsc_env mod location
+
+ src_timestamp <- case maybe_buf of
+ Just (_,t) -> return t
+ Nothing -> getModificationTime file
+ -- getMofificationTime may fail
+
+ obj_timestamp <- modificationTimeIfExists (ml_obj_file location)
+
+ return (ModSummary { ms_mod = mod, ms_hsc_src = HsSrcFile,
+ ms_location = location,
+ ms_hspp_file = Just hspp_fn,
+ ms_hspp_buf = Just buf,
+ ms_srcimps = srcimps, ms_imps = the_imps,
+ ms_hs_date = src_timestamp,
+ ms_obj_date = obj_timestamp })
+
+findSummaryBySourceFile :: [ModSummary] -> FilePath -> Maybe ModSummary
+findSummaryBySourceFile summaries file
+ = case [ ms | ms <- summaries, HsSrcFile <- [ms_hsc_src ms],
+ fromJust (ml_hs_file (ms_location ms)) == file ] of
+ [] -> Nothing
+ (x:xs) -> Just x
+
+-- Summarise a module, and pick up source and timestamp.
+summariseModule
+ :: HscEnv
+ -> NodeMap ModSummary -- Map of old summaries
+ -> IsBootInterface -- True <=> a {-# SOURCE #-} import
+ -> Located Module -- Imported module to be summarised
+ -> Maybe (StringBuffer, ClockTime)
+ -> [Module] -- Modules to exclude
+ -> IO (Maybe ModSummary) -- Its new summary
+
+summariseModule hsc_env old_summary_map is_boot (L loc wanted_mod) maybe_buf excl_mods
+ | wanted_mod `elem` excl_mods
+ = return Nothing
+
+ | Just old_summary <- lookupFM old_summary_map (wanted_mod, hsc_src)
+ = do -- Find its new timestamp; all the
+ -- ModSummaries in the old map have valid ml_hs_files
+ let location = ms_location old_summary
+ src_fn = expectJust "summariseModule" (ml_hs_file location)
+
+ -- check the modification time on the source file, and
+ -- return the cached summary if it hasn't changed. If the
+ -- file has disappeared, we need to call the Finder again.
+ case maybe_buf of
+ Just (_,t) -> check_timestamp old_summary location src_fn t
+ Nothing -> do
+ m <- IO.try (getModificationTime src_fn)
+ case m of
+ Right t -> check_timestamp old_summary location src_fn t
+ Left e | isDoesNotExistError e -> find_it
+ | otherwise -> ioError e
+
+ | otherwise = find_it
+ where
+ dflags = hsc_dflags hsc_env
+
+ hsc_src = if is_boot then HsBootFile else HsSrcFile
+
+ check_timestamp old_summary location src_fn src_timestamp
+ | ms_hs_date old_summary == src_timestamp = do
+ -- update the object-file timestamp
+ obj_timestamp <- getObjTimestamp location is_boot
+ return (Just old_summary{ ms_obj_date = obj_timestamp })
+ | otherwise =
+ -- source changed: find and re-summarise. We call the finder
+ -- again, because the user may have moved the source file.
+ new_summary location src_fn src_timestamp
+
+ find_it = do
+ -- Don't use the Finder's cache this time. If the module was
+ -- previously a package module, it may have now appeared on the
+ -- search path, so we want to consider it to be a home module. If
+ -- the module was previously a home module, it may have moved.
+ uncacheModule hsc_env wanted_mod
+ found <- findModule hsc_env wanted_mod True {-explicit-}
+ case found of
+ Found location pkg
+ | not (isHomePackage pkg) -> return Nothing
+ -- Drop external-pkg
+ | isJust (ml_hs_file location) -> just_found location
+ -- Home package
+ err -> noModError dflags loc wanted_mod err
+ -- Not found
+
+ just_found location = do
+ -- Adjust location to point to the hs-boot source file,
+ -- hi file, object file, when is_boot says so
+ let location' | is_boot = addBootSuffixLocn location
+ | otherwise = location
+ src_fn = expectJust "summarise2" (ml_hs_file location')
+
+ -- Check that it exists
+ -- It might have been deleted since the Finder last found it
+ maybe_t <- modificationTimeIfExists src_fn
+ case maybe_t of
+ Nothing -> noHsFileErr loc src_fn
+ Just t -> new_summary location' src_fn t
+
+
+ new_summary location src_fn src_timestamp
+ = do
+ -- Preprocess the source file and get its imports
+ -- The dflags' contains the OPTIONS pragmas
+ (dflags', hspp_fn, buf) <- preprocessFile dflags src_fn Nothing maybe_buf
+ (srcimps, the_imps, L mod_loc mod_name) <- getImports dflags' buf hspp_fn
+
+ when (mod_name /= wanted_mod) $
+ throwDyn $ mkPlainErrMsg mod_loc $
+ text "file name does not match module name"
+ <+> quotes (ppr mod_name)
+
+ -- Find the object timestamp, and return the summary
+ obj_timestamp <- getObjTimestamp location is_boot
+
+ return (Just ( ModSummary { ms_mod = wanted_mod,
+ ms_hsc_src = hsc_src,
+ ms_location = location,
+ ms_hspp_file = Just hspp_fn,
+ ms_hspp_buf = Just buf,
+ ms_srcimps = srcimps,
+ ms_imps = the_imps,
+ ms_hs_date = src_timestamp,
+ ms_obj_date = obj_timestamp }))
+
+
+getObjTimestamp location is_boot
+ = if is_boot then return Nothing
+ else modificationTimeIfExists (ml_obj_file location)
+
+
+preprocessFile :: DynFlags -> FilePath -> Maybe Phase -> Maybe (StringBuffer,ClockTime)
+ -> IO (DynFlags, FilePath, StringBuffer)
+preprocessFile dflags src_fn mb_phase Nothing
+ = do
+ (dflags', hspp_fn) <- preprocess dflags (src_fn, mb_phase)
+ buf <- hGetStringBuffer hspp_fn
+ return (dflags', hspp_fn, buf)
+
+preprocessFile dflags src_fn mb_phase (Just (buf, time))
+ = do
+ -- case we bypass the preprocessing stage?
+ let
+ local_opts = getOptionsFromStringBuffer buf src_fn
+ --
+ (dflags', errs) <- parseDynamicFlags dflags (map snd local_opts)
+
+ let
+ needs_preprocessing
+ | Just (Unlit _) <- mb_phase = True
+ | Nothing <- mb_phase, Unlit _ <- startPhase src_fn = True
+ -- note: local_opts is only required if there's no Unlit phase
+ | dopt Opt_Cpp dflags' = True
+ | dopt Opt_Pp dflags' = True
+ | otherwise = False
+
+ when needs_preprocessing $
+ ghcError (ProgramError "buffer needs preprocesing; interactive check disabled")
+
+ return (dflags', src_fn, buf)
+
+
+-----------------------------------------------------------------------------
+-- Error messages
+-----------------------------------------------------------------------------
+
+noModError :: DynFlags -> SrcSpan -> Module -> FindResult -> IO ab
+-- ToDo: we don't have a proper line number for this error
+noModError dflags loc wanted_mod err
+ = throwDyn $ mkPlainErrMsg loc $ cantFindError dflags wanted_mod err
+
+noHsFileErr loc path
+ = throwDyn $ mkPlainErrMsg loc $ text "Can't find" <+> text path
+
+packageModErr mod
+ = throwDyn $ mkPlainErrMsg noSrcSpan $
+ text "module" <+> quotes (ppr mod) <+> text "is a package module"
+
+multiRootsErr :: [ModSummary] -> IO ()
+multiRootsErr summs@(summ1:_)
+ = throwDyn $ mkPlainErrMsg noSrcSpan $
+ text "module" <+> quotes (ppr mod) <+>
+ text "is defined in multiple files:" <+>
+ sep (map text files)
+ where
+ mod = ms_mod summ1
+ files = map (expectJust "checkDup" . ml_hs_file . ms_location) summs
+
+cyclicModuleErr :: [ModSummary] -> SDoc
+cyclicModuleErr ms
+ = hang (ptext SLIT("Module imports form a cycle for modules:"))
+ 2 (vcat (map show_one ms))
+ where
+ show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
+ nest 2 $ ptext SLIT("imports:") <+>
+ (pp_imps HsBootFile (ms_srcimps ms)
+ $$ pp_imps HsSrcFile (ms_imps ms))]
+ show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
+ pp_imps src mods = fsep (map (show_mod src) mods)
+
+
+-- | Inform GHC that the working directory has changed. GHC will flush
+-- its cache of module locations, since it may no longer be valid.
+-- Note: if you change the working directory, you should also unload
+-- the current program (set targets to empty, followed by load).
+workingDirectoryChanged :: Session -> IO ()
+workingDirectoryChanged s = withSession s $ \hsc_env ->
+ flushFinderCache (hsc_FC hsc_env)
+
+-- -----------------------------------------------------------------------------
+-- inspecting the session
+
+-- | Get the module dependency graph.
+getModuleGraph :: Session -> IO ModuleGraph -- ToDo: DiGraph ModSummary
+getModuleGraph s = withSession s (return . hsc_mod_graph)
+
+isLoaded :: Session -> Module -> IO Bool
+isLoaded s m = withSession s $ \hsc_env ->
+ return $! isJust (lookupModuleEnv (hsc_HPT hsc_env) m)
+
+getBindings :: Session -> IO [TyThing]
+getBindings s = withSession s (return . nameEnvElts . ic_type_env . hsc_IC)
+
+getPrintUnqual :: Session -> IO PrintUnqualified
+getPrintUnqual s = withSession s (return . icPrintUnqual . hsc_IC)
+
+-- | Container for information about a 'Module'.
+data ModuleInfo = ModuleInfo {
+ minf_type_env :: TypeEnv,
+ minf_exports :: NameSet,
+ minf_rdr_env :: Maybe GlobalRdrEnv, -- Nothing for a compiled/package mod
+ minf_instances :: [Instance]
+ -- ToDo: this should really contain the ModIface too
+ }
+ -- We don't want HomeModInfo here, because a ModuleInfo applies
+ -- to package modules too.
+
+-- | Request information about a loaded 'Module'
+getModuleInfo :: Session -> Module -> IO (Maybe ModuleInfo)
+getModuleInfo s mdl = withSession s $ \hsc_env -> do
+ let mg = hsc_mod_graph hsc_env
+ if mdl `elem` map ms_mod mg
+ then getHomeModuleInfo hsc_env mdl
+ else do
+ {- if isHomeModule (hsc_dflags hsc_env) mdl
+ then return Nothing
+ else -} getPackageModuleInfo hsc_env mdl
+ -- getPackageModuleInfo will attempt to find the interface, so
+ -- we don't want to call it for a home module, just in case there
+ -- was a problem loading the module and the interface doesn't
+ -- exist... hence the isHomeModule test here. (ToDo: reinstate)
+
+getPackageModuleInfo :: HscEnv -> Module -> IO (Maybe ModuleInfo)
+getPackageModuleInfo hsc_env mdl = do
+#ifdef GHCI
+ (_msgs, mb_names) <- getModuleExports hsc_env mdl
+ case mb_names of
+ Nothing -> return Nothing
+ Just names -> do
+ eps <- readIORef (hsc_EPS hsc_env)
+ let
+ pte = eps_PTE eps
+ n_list = nameSetToList names
+ tys = [ ty | name <- n_list,
+ Just ty <- [lookupTypeEnv pte name] ]
+ --
+ return (Just (ModuleInfo {
+ minf_type_env = mkTypeEnv tys,
+ minf_exports = names,
+ minf_rdr_env = Just $! nameSetToGlobalRdrEnv names mdl,
+ minf_instances = error "getModuleInfo: instances for package module unimplemented"
+ }))
+#else
+ -- bogusly different for non-GHCI (ToDo)
+ return Nothing
+#endif
+
+getHomeModuleInfo hsc_env mdl =
+ case lookupModuleEnv (hsc_HPT hsc_env) mdl of
+ Nothing -> return Nothing
+ Just hmi -> do
+ let details = hm_details hmi
+ return (Just (ModuleInfo {
+ minf_type_env = md_types details,
+ minf_exports = md_exports details,
+ minf_rdr_env = mi_globals $! hm_iface hmi,
+ minf_instances = md_insts details
+ }))
+
+-- | The list of top-level entities defined in a module
+modInfoTyThings :: ModuleInfo -> [TyThing]
+modInfoTyThings minf = typeEnvElts (minf_type_env minf)
+
+modInfoTopLevelScope :: ModuleInfo -> Maybe [Name]
+modInfoTopLevelScope minf
+ = fmap (map gre_name . globalRdrEnvElts) (minf_rdr_env minf)
+
+modInfoExports :: ModuleInfo -> [Name]
+modInfoExports minf = nameSetToList $! minf_exports minf
+
+-- | Returns the instances defined by the specified module.
+-- Warning: currently unimplemented for package modules.
+modInfoInstances :: ModuleInfo -> [Instance]
+modInfoInstances = minf_instances
+
+modInfoIsExportedName :: ModuleInfo -> Name -> Bool
+modInfoIsExportedName minf name = elemNameSet name (minf_exports minf)
+
+modInfoPrintUnqualified :: ModuleInfo -> Maybe PrintUnqualified
+modInfoPrintUnqualified minf = fmap unQualInScope (minf_rdr_env minf)
+
+modInfoLookupName :: Session -> ModuleInfo -> Name -> IO (Maybe TyThing)
+modInfoLookupName s minf name = withSession s $ \hsc_env -> do
+ case lookupTypeEnv (minf_type_env minf) name of
+ Just tyThing -> return (Just tyThing)
+ Nothing -> do
+ eps <- readIORef (hsc_EPS hsc_env)
+ return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
+
+isDictonaryId :: Id -> Bool
+isDictonaryId id
+ = case tcSplitSigmaTy (idType id) of { (tvs, theta, tau) -> isDictTy tau }
+
+-- | Looks up a global name: that is, any top-level name in any
+-- visible module. Unlike 'lookupName', lookupGlobalName does not use
+-- the interactive context, and therefore does not require a preceding
+-- 'setContext'.
+lookupGlobalName :: Session -> Name -> IO (Maybe TyThing)
+lookupGlobalName s name = withSession s $ \hsc_env -> do
+ eps <- readIORef (hsc_EPS hsc_env)
+ return $! lookupType (hsc_HPT hsc_env) (eps_PTE eps) name
+
+-- -----------------------------------------------------------------------------
+-- Misc exported utils
+
+dataConType :: DataCon -> Type
+dataConType dc = idType (dataConWrapId dc)
+
+-- | print a 'NamedThing', adding parentheses if the name is an operator.
+pprParenSymName :: NamedThing a => a -> SDoc
+pprParenSymName a = parenSymOcc (getOccName a) (ppr (getName a))
+
+-- ----------------------------------------------------------------------------
+
+#if 0
+
+-- ToDo:
+-- - Data and Typeable instances for HsSyn.
+