2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
7 showIface, -- Print the iface in Foo.hi
9 mkUsageInfo, -- Construct the usage info for a module
11 mkIface, -- Build a ModIface from a ModGuts,
12 -- including computing version information
14 checkOldIface -- See if recompilation is required, by
15 -- comparing version information
19 -----------------------------------------------
20 MkIface.lhs deals with versioning
21 -----------------------------------------------
23 Here's the version-related info in an interface file
25 module Foo 8 -- module-version
26 3 -- export-list-version
28 Usages: -- Version info for what this compilation of Foo imported
29 Baz 3 -- Module version
30 [4] -- The export-list version if Foo depended on it
31 (g,2) -- Function and its version
32 (T,1) -- Type and its version
34 <version> f :: Int -> Int {- Unfolding: \x -> Wib.t[2] x -}
35 -- The [2] says that f's unfolding
36 -- mentions verison 2 of Wib.t
38 -----------------------------------------------
40 -----------------------------------------------
43 * In the mi_usages information in an interface, we record the
44 version number of each free variable of the module
46 * In mkIface, we compute the version number of each exported thing A.f
47 by comparing its A.f's info with its new info, and bumping its
48 version number if it differs. If A.f mentions B.g, and B.g's version
49 number has changed, then we count A.f as having changed too.
51 * In checkOldIface we compare the mi_usages for the module with
52 the actual version info for all each thing recorded in mi_usages
57 We count A.f as changing if its fixity changes
61 If a rule changes, we want to recompile any module that might be
62 affected by that rule. For non-orphan rules, this is relatively easy.
63 If module M defines f, and a rule for f, just arrange that the version
64 number for M.f changes if any of the rules for M.f change. Any module
65 that does not depend on M.f can't be affected by the rule-change
68 Orphan rules (ones whose 'head function' is not defined in M) are
69 harder. Here's what we do.
71 * We have a per-module orphan-rule version number which changes if
72 any orphan rule changes. (It's unaffected by non-orphan rules.)
74 * We record usage info for any orphan module 'below' this one,
75 giving the orphan-rule version number. We recompile if this
78 The net effect is that if an orphan rule changes, we recompile every
79 module above it. That's very conservative, but it's devilishly hard
80 to know what it might affect, so we just have to be conservative.
84 In an iface file we have
86 instance Eq a => Eq [a] = dfun29
89 We have a version number for dfun29, covering its unfolding
90 etc. Suppose we are compiling a module M that imports A only
91 indirectly. If typechecking M uses this instance decl, we record the
92 dependency on A.dfun29 as if it were a free variable of the module
93 (via the tcg_inst_usages accumulator). That means that A will appear
94 in M's usage list. If the shape of the instance declaration changes,
95 then so will dfun29's version, triggering a recompilation.
97 Adding an instance declaration, or changing an instance decl that is
98 not currently used, is more tricky. (This really only makes a
99 difference when we have overlapping instance decls, because then the
100 new instance decl might kick in to override the old one.) We handle
101 this in a very similar way that we handle rules above.
103 * For non-orphan instance decls, identify one locally-defined tycon/class
104 mentioned in the decl. Treat the instance decl as part of the defn of that
105 tycon/class, so that if the shape of the instance decl changes, so does the
106 tycon/class; that in turn will force recompilation of anything that uses
109 * For orphan instance decls, act the same way as for orphan rules.
110 Indeed, we use the same global orphan-rule version number.
114 mkUsageInfo figures out what the ``usage information'' for this
115 moudule is; that is, what it must record in its interface file as the
118 We produce a line for every module B below the module, A, currently being
121 to record the fact that A does import B indirectly. This is used to decide
122 to look to look for B.hi rather than B.hi-boot when compiling a module that
123 imports A. This line says that A imports B, but uses nothing in it.
124 So we'll get an early bale-out when compiling A if B's version changes.
126 The usage information records:
129 \item (a) anything reachable from its body code
130 \item (b) any module exported with a @module Foo@
131 \item (c) anything reachable from an exported item
134 Why (b)? Because if @Foo@ changes then this module's export list
135 will change, so we must recompile this module at least as far as
136 making a new interface file --- but in practice that means complete
139 Why (c)? Consider this:
141 module A( f, g ) where | module B( f ) where
142 import B( f ) | f = h 3
146 Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in
147 @A@'s usages? Our idea is that we aren't going to touch A.hi if it is
148 *identical* to what it was before. If anything about @B.f@ changes
149 than anyone who imports @A@ should be recompiled in case they use
150 @B.f@ (they'll get an early exit if they don't). So, if anything
151 about @B.f@ changes we'd better make sure that something in A.hi
152 changes, and the convenient way to do that is to record the version
153 number @B.f@ in A.hi in the usage list. If B.f changes that'll force a
154 complete recompiation of A, which is overkill but it's the only way to
155 write a new, slightly different, A.hi.
157 But the example is tricker. Even if @B.f@ doesn't change at all,
158 @B.h@ may do so, and this change may not be reflected in @f@'s version
159 number. But with -O, a module that imports A must be recompiled if
160 @B.h@ changes! So A must record a dependency on @B.h@. So we treat
161 the occurrence of @B.f@ in the export list *just as if* it were in the
162 code of A, and thereby haul in all the stuff reachable from it.
164 *** Conclusion: if A mentions B.f in its export list,
165 behave just as if A mentioned B.f in its source code,
166 and slurp in B.f and all its transitive closure ***
168 [NB: If B was compiled with -O, but A isn't, we should really *still*
169 haul in all the unfoldings for B, in case the module that imports A *is*
170 compiled with -O. I think this is the case.]
174 #include "HsVersions.h"
177 import Packages ( isHomeModule, PackageIdH(..) )
178 import IfaceSyn ( IfaceDecl(..), IfaceClassOp(..), IfaceConDecl(..),
179 IfaceRule(..), IfaceInst(..), IfaceExtName(..), IfaceTyCon(..),
180 eqIfDecl, eqIfRule, eqIfInst, IfaceEq(..), (&&&), bool,
181 eqMaybeBy, eqListBy, visibleIfConDecls,
182 tyThingToIfaceDecl, dfunToIfaceInst, coreRuleToIfaceRule )
183 import LoadIface ( readIface, loadInterface, ifaceInstGates )
184 import BasicTypes ( Version, initialVersion, bumpVersion )
186 import TcRnTypes ( mkModDeps )
187 import TcType ( isFFITy )
188 import HscTypes ( ModIface(..), TyThing(..),
189 ModGuts(..), ModGuts, IfaceExport,
190 GhciMode(..), HscEnv(..), hscEPS,
191 Dependencies(..), FixItem(..),
192 mkIfaceDepCache, mkIfaceFixCache, mkIfaceVerCache,
194 GenAvailInfo(..), availName,
195 ExternalPackageState(..),
196 Usage(..), IsBootInterface,
197 Deprecs(..), IfaceDeprecs, Deprecations,
203 import Name ( Name, nameModule, nameOccName, nameParent,
204 isExternalName, nameParent_maybe, isWiredInName,
208 import OccName ( OccName, OccEnv, mkOccEnv, lookupOccEnv, emptyOccEnv,
210 OccSet, emptyOccSet, elemOccSet, occSetElts,
211 extendOccSet, extendOccSetList,
212 isEmptyOccSet, intersectOccSet, intersectsOccSet,
214 import TyCon ( tyConDataCons, isNewTyCon, newTyConRep )
215 import Class ( classSelIds )
216 import DataCon ( dataConName, dataConFieldLabels )
217 import Module ( Module, moduleFS,
218 ModLocation(..), mkSysModuleFS, moduleUserString,
219 ModuleEnv, emptyModuleEnv, lookupModuleEnv,
223 import DriverUtil ( createDirectoryHierarchy, directoryOf )
224 import Util ( sortLe, seqList )
225 import Binary ( getBinFileWithDict )
226 import BinIface ( writeBinIface, v_IgnoreHiWay )
227 import Unique ( Unique, Uniquable(..) )
228 import ErrUtils ( dumpIfSet_dyn, showPass )
229 import Digraph ( stronglyConnComp, SCC(..) )
230 import SrcLoc ( SrcSpan )
234 import DATA_IOREF ( writeIORef )
235 import Monad ( when )
236 import List ( insert )
237 import Maybes ( orElse, mapCatMaybes, isNothing, isJust,
238 fromJust, expectJust, MaybeErr(..) )
243 %************************************************************************
245 \subsection{Completing an interface}
247 %************************************************************************
252 -> Maybe ModIface -- The old interface, if we have it
253 -> ModGuts -- The compiled, tidied module
254 -> IO ModIface -- The new one, complete with decls and versions
256 -- a) Builds the ModIface
257 -- b) Writes it out to a file if necessary
259 mkIface hsc_env location maybe_old_iface
260 guts@ModGuts{ mg_module = this_mod,
263 mg_exports = exports,
264 mg_fix_env = fix_env,
265 mg_deprecs = src_deprecs,
268 mg_types = type_env }
269 = do { eps <- hscEPS hsc_env
270 ; let { ext_nm = mkExtNameFn hsc_env eps this_mod
271 ; local_things = [thing | thing <- typeEnvElts type_env,
272 not (isWiredInName (getName thing)) ]
273 -- Do not export anything about wired-in things
274 -- (GHC knows about them already)
276 ; abstract_tcs :: NameSet -- TyCons and Classes whose representation is not exposed
278 | not omit_prags = emptyNameSet -- In the -O case, nothing is abstract
279 | otherwise = mkNameSet [ getName thing
280 | thing <- local_things
281 , not (mustExposeThing exports thing)]
283 ; decls = [ tyThingToIfaceDecl omit_prags abstract_tcs ext_nm thing
284 | thing <- local_things, wantDeclFor exports abstract_tcs thing ]
285 -- Don't put implicit Ids and class tycons in the interface file
287 ; fixities = [(occ,fix) | FixItem occ fix _ <- nameEnvElts fix_env]
288 ; deprecs = mkIfaceDeprec src_deprecs
291 | otherwise = sortLe le_rule $
292 map (coreRuleToIfaceRule this_mod ext_nm) rules
293 ; iface_insts = sortLe le_inst (map dfunToIfaceInst insts)
295 ; intermediate_iface = ModIface {
296 mi_module = this_mod,
297 mi_package = HomePackage,
301 mi_exports = mkIfaceExports exports,
302 mi_insts = iface_insts,
303 mi_rules = iface_rules,
304 mi_fixities = fixities,
305 mi_deprecs = deprecs,
307 -- Left out deliberately: filled in by addVersionInfo
308 mi_mod_vers = initialVersion,
309 mi_exp_vers = initialVersion,
310 mi_rule_vers = initialVersion,
311 mi_orphan = False, -- Always set by addVersionInfo, but
312 -- it's a strict field, so we can't omit it.
313 mi_decls = deliberatelyOmitted "decls",
314 mi_ver_fn = deliberatelyOmitted "ver_fn",
316 -- And build the cached values
317 mi_dep_fn = mkIfaceDepCache deprecs,
318 mi_fix_fn = mkIfaceFixCache fixities }
320 -- Add version information
321 ; (new_iface, no_change_at_all, pp_diffs, pp_orphs)
322 = _scc_ "versioninfo"
323 addVersionInfo maybe_old_iface intermediate_iface decls
326 -- Write the interface file, if necessary
327 ; when (not no_change_at_all && ghci_mode /= Interactive) $ do
328 createDirectoryHierarchy (directoryOf hi_file_path)
329 writeBinIface hi_file_path new_iface
332 ; when (isJust pp_orphs && dopt Opt_WarnOrphans dflags)
333 (printDump (fromJust pp_orphs))
334 ; when (dopt Opt_D_dump_hi_diffs dflags) (printDump pp_diffs)
335 ; dumpIfSet_dyn dflags Opt_D_dump_hi "FINAL INTERFACE"
336 (pprModIface new_iface)
340 r1 `le_rule` r2 = ifRuleName r1 <= ifRuleName r2
341 i1 `le_inst` i2 = ifDFun i1 <= ifDFun i2
343 dflags = hsc_dflags hsc_env
344 ghci_mode = hsc_mode hsc_env
345 hi_file_path = ml_hi_file location
346 omit_prags = dopt Opt_OmitInterfacePragmas dflags
349 mustExposeThing :: NameSet -> TyThing -> Bool
350 -- We are compiling without -O, and thus trying to write as little as
351 -- possible into the interface file. But we must expose the details of
352 -- any data types and classes whose constructors, fields, methods are
353 -- visible to an importing module
354 mustExposeThing exports (ATyCon tc)
355 = any exported_data_con (tyConDataCons tc)
356 -- Expose rep if any datacon or field is exported
358 || (isNewTyCon tc && isFFITy (snd (newTyConRep tc)))
359 -- Expose the rep for newtypes if the rep is an FFI type.
360 -- For a very annoying reason. 'Foreign import' is meant to
361 -- be able to look through newtypes transparently, but it
362 -- can only do that if it can "see" the newtype representation
364 exported_data_con con
365 = any (`elemNameSet` exports) (dataConName con : dataConFieldLabels con)
367 mustExposeThing exports (AClass cls)
368 = any exported_class_op (classSelIds cls)
369 where -- Expose rep if any classs op is exported
370 exported_class_op op = getName op `elemNameSet` exports
372 mustExposeThing exports other = False
375 wantDeclFor :: NameSet -- User-exported things
376 -> NameSet -- Abstract things
378 wantDeclFor exports abstracts thing
379 | Just parent <- nameParent_maybe name -- An implicit thing
380 = parent `elemNameSet` abstracts && name `elemNameSet` exports
387 deliberatelyOmitted x = panic ("Deliberately omitted: " ++ x)
389 -----------------------------
390 mkExtNameFn :: HscEnv -> ExternalPackageState -> Module -> Name -> IfaceExtName
391 mkExtNameFn hsc_env eps this_mod
394 dflags = hsc_dflags hsc_env
395 hpt = hsc_HPT hsc_env
399 | mod == this_mod = case nameParent_maybe name of
400 Nothing -> LocalTop occ
401 Just par -> LocalTopSub occ (nameOccName par)
402 | isWiredInName name = ExtPkg mod occ
403 | isHomeModule dflags mod = HomePkg mod occ vers
404 | otherwise = ExtPkg mod occ
406 mod = nameModule name
407 occ = nameOccName name
408 par_occ = nameOccName (nameParent name)
409 -- The version of the *parent* is the one want
410 vers = lookupVersion mod par_occ
412 lookupVersion :: Module -> OccName -> Version
413 -- Even though we're looking up a home-package thing, in
414 -- one-shot mode the imported interfaces may be in the PIT
415 lookupVersion mod occ
416 = mi_ver_fn iface occ `orElse`
417 pprPanic "lookupVers1" (ppr mod <+> ppr occ)
419 iface = lookupIfaceByModule hpt pit mod `orElse`
420 pprPanic "lookupVers2" (ppr mod <+> ppr occ)
422 -----------------------------
423 -- Compute version numbers for local decls
425 addVersionInfo :: Maybe ModIface -- The old interface, read from M.hi
426 -> ModIface -- The new interface decls (lacking decls)
427 -> [IfaceDecl] -- The new decls
429 Bool, -- True <=> no changes at all; no need to write new Iface
431 Maybe SDoc) -- Warnings about orphans
433 addVersionInfo Nothing new_iface new_decls
434 -- No old interface, so definitely write a new one!
435 = (new_iface { mi_orphan = anyNothing getInstKey (mi_insts new_iface)
436 || anyNothing getRuleKey (mi_rules new_iface),
437 mi_decls = [(initialVersion, decl) | decl <- new_decls],
438 mi_ver_fn = \n -> Just initialVersion },
440 ptext SLIT("No old interface file"),
441 pprOrphans orph_insts orph_rules)
443 orph_insts = filter (isNothing . getInstKey) (mi_insts new_iface)
444 orph_rules = filter (isNothing . getRuleKey) (mi_rules new_iface)
446 addVersionInfo (Just old_iface@(ModIface { mi_mod_vers = old_mod_vers,
447 mi_exp_vers = old_exp_vers,
448 mi_rule_vers = old_rule_vers,
449 mi_decls = old_decls,
450 mi_ver_fn = old_decl_vers,
451 mi_fix_fn = old_fixities }))
452 new_iface@(ModIface { mi_fix_fn = new_fixities })
455 | no_change_at_all = (old_iface, True, ptext SLIT("Interface file unchanged"), pp_orphs)
456 | otherwise = (final_iface, False, vcat [ptext SLIT("Interface file has changed"),
457 nest 2 pp_diffs], pp_orphs)
459 final_iface = new_iface { mi_mod_vers = bump_unless no_output_change old_mod_vers,
460 mi_exp_vers = bump_unless no_export_change old_exp_vers,
461 mi_rule_vers = bump_unless no_rule_change old_rule_vers,
462 mi_orphan = not (null new_orph_rules && null new_orph_insts),
463 mi_decls = decls_w_vers,
464 mi_ver_fn = mkIfaceVerCache decls_w_vers }
466 decls_w_vers = [(add_vers decl, decl) | decl <- new_decls]
469 (old_non_orph_insts, old_orph_insts) = mkRuleMap getInstKey (mi_insts old_iface)
470 (new_non_orph_insts, new_orph_insts) = mkRuleMap getInstKey (mi_insts new_iface)
471 same_insts occ = eqMaybeBy (eqListBy eqIfInst)
472 (lookupOccEnv old_non_orph_insts occ)
473 (lookupOccEnv new_non_orph_insts occ)
475 (old_non_orph_rules, old_orph_rules) = mkRuleMap getRuleKey (mi_rules old_iface)
476 (new_non_orph_rules, new_orph_rules) = mkRuleMap getRuleKey (mi_rules new_iface)
477 same_rules occ = eqMaybeBy (eqListBy eqIfRule)
478 (lookupOccEnv old_non_orph_rules occ)
479 (lookupOccEnv new_non_orph_rules occ)
481 -- Computing what changed
482 no_output_change = no_decl_change && no_rule_change &&
483 no_export_change && no_deprec_change
484 no_export_change = mi_exports new_iface == mi_exports old_iface -- Kept sorted
485 no_decl_change = isEmptyOccSet changed_occs
486 no_rule_change = not (changedWrt changed_occs (eqListBy eqIfRule old_orph_rules new_orph_rules)
487 || changedWrt changed_occs (eqListBy eqIfInst old_orph_insts new_orph_insts))
488 no_deprec_change = mi_deprecs new_iface == mi_deprecs old_iface
490 -- If the usages havn't changed either, we don't need to write the interface file
491 no_other_changes = mi_usages new_iface == mi_usages old_iface &&
492 mi_deps new_iface == mi_deps old_iface
493 no_change_at_all = no_output_change && no_other_changes
495 pp_diffs = vcat [pp_change no_export_change "Export list"
496 (ppr old_exp_vers <+> arrow <+> ppr (mi_exp_vers final_iface)),
497 pp_change no_rule_change "Rules"
498 (ppr old_rule_vers <+> arrow <+> ppr (mi_rule_vers final_iface)),
499 pp_change no_deprec_change "Deprecations" empty,
500 pp_change no_other_changes "Usages" empty,
502 pp_change True what info = empty
503 pp_change False what info = text what <+> ptext SLIT("changed") <+> info
506 old_decl_env = mkOccEnv [(ifName decl, decl) | (_,decl) <- old_decls]
507 same_fixity n = bool (old_fixities n == new_fixities n)
510 -- Adding version info
511 new_version = bumpVersion old_mod_vers
512 add_vers decl | occ `elemOccSet` changed_occs = new_version
513 | otherwise = expectJust "add_vers" (old_decl_vers occ)
514 -- If it's unchanged, there jolly well
515 where -- should be an old version number
519 changed_occs :: OccSet
520 changed_occs = computeChangedOccs eq_info
522 eq_info :: [(OccName, IfaceEq)]
523 eq_info = map check_eq new_decls
524 check_eq new_decl | Just old_decl <- lookupOccEnv old_decl_env occ
525 = (occ, new_decl `eqIfDecl` old_decl &&&
526 eq_indirects new_decl)
527 | otherwise {- No corresponding old decl -}
530 occ = ifName new_decl
532 eq_indirects :: IfaceDecl -> IfaceEq
533 -- When seeing if two decls are the same, remember to
534 -- check whether any relevant fixity or rules have changed
535 eq_indirects (IfaceId {ifName = occ}) = eq_ind_occ occ
536 eq_indirects (IfaceClass {ifName = cls_occ, ifSigs = sigs})
537 = same_insts cls_occ &&&
538 eq_ind_occs [op | IfaceClassOp op _ _ <- sigs]
539 eq_indirects (IfaceData {ifName = tc_occ, ifCons = cons})
540 = same_insts tc_occ &&& same_fixity tc_occ &&& -- The TyCon can have a fixity too
541 eq_ind_occs (map ifConOcc (visibleIfConDecls cons))
542 eq_indirects other = Equal -- Synonyms and foreign declarations
544 eq_ind_occ :: OccName -> IfaceEq -- For class ops and Ids; check fixity and rules
545 eq_ind_occ occ = same_fixity occ &&& same_rules occ
546 eq_ind_occs = foldr ((&&&) . eq_ind_occ) Equal
550 pp_decl_diffs :: SDoc -- Nothing => no changes
552 | isEmptyOccSet changed_occs = empty
554 = vcat [ptext SLIT("Changed occs:") <+> ppr (occSetElts changed_occs),
555 ptext SLIT("Version change for these decls:"),
556 nest 2 (vcat (map show_change new_decls))]
558 eq_env = mkOccEnv eq_info
560 | not (occ `elemOccSet` changed_occs) = empty
562 = vcat [ppr occ <+> ppr (old_decl_vers occ) <+> arrow <+> ppr new_version,
565 occ = ifName new_decl
566 why = case lookupOccEnv eq_env occ of
567 Just (EqBut occs) -> sep [ppr occ <> colon, ptext SLIT("Free vars (only) changed:"),
568 nest 2 (braces (fsep (map ppr (occSetElts
569 (occs `intersectOccSet` changed_occs)))))]
571 | Just old_decl <- lookupOccEnv old_decl_env occ
572 -> vcat [ptext SLIT("Old:") <+> ppr old_decl,
573 ptext SLIT("New:") <+> ppr new_decl]
575 -> ppr occ <+> ptext SLIT("only in new interface")
576 other -> pprPanic "MkIface.show_change" (ppr occ)
578 pp_orphs = pprOrphans new_orph_insts new_orph_rules
580 pprOrphans insts rules
581 | null insts && null rules = Nothing
584 if null insts then empty else
585 hang (ptext SLIT("Warning: orphan instances:"))
586 2 (vcat (map ppr insts)),
587 if null rules then empty else
588 hang (ptext SLIT("Warning: orphan rules:"))
589 2 (vcat (map ppr rules))
592 computeChangedOccs :: [(OccName, IfaceEq)] -> OccSet
593 computeChangedOccs eq_info
594 = foldl add_changes emptyOccSet (stronglyConnComp edges)
596 edges :: [((OccName,IfaceEq), Unique, [Unique])]
597 edges = [ (node, getUnique occ, map getUnique occs)
598 | node@(occ, iface_eq) <- eq_info
599 , let occs = case iface_eq of
600 EqBut occ_set -> occSetElts occ_set
603 -- Changes in declarations
604 add_changes :: OccSet -> SCC (OccName, IfaceEq) -> OccSet
605 add_changes so_far (AcyclicSCC (occ, iface_eq))
606 | changedWrt so_far iface_eq -- This one has changed
607 = extendOccSet so_far occ
608 add_changes so_far (CyclicSCC pairs)
609 | changedWrt so_far (foldr1 (&&&) (map snd pairs)) -- One of this group has changed
610 = extendOccSetList so_far (map fst pairs)
611 add_changes so_far other = so_far
613 changedWrt :: OccSet -> IfaceEq -> Bool
614 changedWrt so_far Equal = False
615 changedWrt so_far NotEqual = True
616 changedWrt so_far (EqBut kids) = so_far `intersectsOccSet` kids
618 ----------------------
619 -- mkRuleMap partitions instance decls or rules into
620 -- (a) an OccEnv for ones that are not orphans,
621 -- mapping the local OccName to a list of its decls
622 -- (b) a list of orphan decls
623 mkRuleMap :: (decl -> Maybe OccName) -- (Just occ) for a non-orphan decl, keyed by occ
624 -- Nothing for an orphan decl
625 -> [decl] -- Sorted into canonical order
626 -> (OccEnv [decl], -- Non-orphan decls associated with their key;
627 -- each sublist in canonical order
628 [decl]) -- Orphan decls; in canonical order
629 mkRuleMap get_key decls
630 = foldl go (emptyOccEnv, []) decls
632 go (non_orphs, orphs) d
633 | Just occ <- get_key d
634 = (extendOccEnv_C (\ ds _ -> d:ds) non_orphs occ [d], orphs)
635 | otherwise = (non_orphs, d:orphs)
637 -- getXxKey: find at least one local OccName that belongs to this decl
639 getInstKey :: IfaceInst -> Maybe OccName
640 getInstKey (IfaceInst {ifInstHead = inst_ty})
641 = case [occ | LocalTop occ <- cls_ext : tc_exts] of
645 (cls_ext, tcs) = ifaceInstGates inst_ty
646 tc_exts = [tc | IfaceTc tc <- tcs]
647 -- Ignore the wired-in IfaceTyCons; the class will do as the key
649 getRuleKey :: IfaceRule -> Maybe OccName
650 getRuleKey (IfaceRule {ifRuleHead = LocalTop occ}) = Just occ
651 getRuleKey other = Nothing
653 anyNothing :: (a -> Maybe b) -> [a] -> Bool
654 anyNothing p [] = False
655 anyNothing p (x:xs) = isNothing (p x) || anyNothing p xs
657 ----------------------
658 mkIfaceDeprec :: Deprecations -> IfaceDeprecs
659 mkIfaceDeprec NoDeprecs = NoDeprecs
660 mkIfaceDeprec (DeprecAll t) = DeprecAll t
661 mkIfaceDeprec (DeprecSome env) = DeprecSome (sortLe (<=) (nameEnvElts env))
663 ----------------------
664 bump_unless :: Bool -> Version -> Version
665 bump_unless True v = v -- True <=> no change
666 bump_unless False v = bumpVersion v
670 %*********************************************************
672 \subsection{Keeping track of what we've slurped, and version numbers}
674 %*********************************************************
678 mkUsageInfo :: HscEnv
679 -> ModuleEnv (Module, Maybe Bool, SrcSpan)
680 -> [(Module, IsBootInterface)]
681 -> NameSet -> IO [Usage]
682 mkUsageInfo hsc_env dir_imp_mods dep_mods used_names
683 = do { eps <- hscEPS hsc_env
684 ; let usages = mk_usage_info (eps_PIT eps) hsc_env
685 dir_imp_mods dep_mods used_names
686 ; usages `seqList` return usages }
687 -- seq the list of Usages returned: occasionally these
688 -- don't get evaluated for a while and we can end up hanging on to
689 -- the entire collection of Ifaces.
691 mk_usage_info pit hsc_env dir_imp_mods dep_mods proto_used_names
692 = mapCatMaybes mkUsage dep_mods
693 -- ToDo: do we need to sort into canonical order?
695 dflags = hsc_dflags hsc_env
696 hpt = hsc_HPT hsc_env
698 used_names = mkNameSet $ -- Eliminate duplicates
699 [ nameParent n -- Just record usage on the 'main' names
700 | n <- nameSetToList proto_used_names
701 , not (isWiredInName n) -- Don't record usages for wired-in names
702 , isExternalName n -- Ignore internal names
705 -- ent_map groups together all the things imported and used
706 -- from a particular module in this package
707 ent_map :: ModuleEnv [OccName]
708 ent_map = foldNameSet add_mv emptyModuleEnv used_names
709 add_mv name mv_map = extendModuleEnv_C add_item mv_map mod [occ]
711 occ = nameOccName name
712 mod = nameModule name
713 add_item occs _ = occ:occs
715 import_all mod = case lookupModuleEnv dir_imp_mods mod of
716 Just (_,imp_all,_) -> isNothing imp_all
719 -- We want to create a Usage for a home module if
720 -- a) we used something from; has something in used_names
721 -- b) we imported all of it, even if we used nothing from it
722 -- (need to recompile if its export list changes: export_vers)
723 -- c) is a home-package orphan module (need to recompile if its
724 -- instance decls change: rules_vers)
725 mkUsage :: (Module, Bool) -> Maybe Usage
726 mkUsage (mod_name, _)
727 | isNothing maybe_iface -- We can't depend on it if we didn't
728 || not (isHomeModule dflags mod) -- even open the interface!
732 = Nothing -- Record no usage info
735 = Just (Usage { usg_name = mod,
737 usg_exports = export_vers,
738 usg_entities = ent_vers,
739 usg_rules = rules_vers })
741 maybe_iface = lookupIfaceByModule hpt pit mod_name
742 -- In one-shot mode, the interfaces for home-package
743 -- modules accumulate in the PIT not HPT. Sigh.
745 Just iface = maybe_iface
746 mod = mi_module iface
747 orphan_mod = mi_orphan iface
748 version_env = mi_ver_fn iface
749 mod_vers = mi_mod_vers iface
750 rules_vers = mi_rule_vers iface
751 all_imported = import_all mod
752 export_vers | all_imported = Just (mi_exp_vers iface)
753 | otherwise = Nothing
755 -- The sort is to put them into canonical order
756 used_occs = lookupModuleEnv ent_map mod `orElse` []
757 ent_vers :: [(OccName,Version)]
758 ent_vers = [ (occ, version_env occ `orElse` initialVersion)
759 | occ <- sortLe (<=) used_occs]
763 mkIfaceExports :: NameSet -> [(Module, [GenAvailInfo OccName])]
764 -- Group by module and sort by occurrence
765 -- This keeps the list in canonical order
766 mkIfaceExports exports
767 = [ (mkSysModuleFS fs, eltsFM avails)
768 | (fs, avails) <- fmToList groupFM
771 groupFM :: FiniteMap FastString (FiniteMap FastString (GenAvailInfo OccName))
772 -- Deliberately use the FastString so we
773 -- get a canonical ordering
774 groupFM = foldl add emptyFM (nameSetToList exports)
776 add env name = addToFM_C add_avail env mod_fs
777 (unitFM avail_fs avail)
779 occ = nameOccName name
780 mod_fs = moduleFS (nameModule name)
781 avail | Just p <- nameParent_maybe name = AvailTC (nameOccName p) [occ]
782 | isTcOcc occ = AvailTC occ [occ]
783 | otherwise = Avail occ
784 avail_fs = occNameFS (availName avail)
785 add_avail avail_fm _ = addToFM_C add_item avail_fm avail_fs avail
787 add_item (AvailTC p occs) _ = AvailTC p (List.insert occ occs)
788 add_item (Avail n) _ = pprPanic "MkIface.addAvail" (ppr n <+> ppr name)
792 %************************************************************************
794 Load the old interface file for this module (unless
795 we have it aleady), and check whether it is up to date
798 %************************************************************************
801 checkOldIface :: HscEnv
803 -> FilePath -- Where the interface file is
804 -> Bool -- Source unchanged
805 -> Maybe ModIface -- Old interface from compilation manager, if any
806 -> IO (RecompileRequired, Maybe ModIface)
808 checkOldIface hsc_env mod iface_path source_unchanged maybe_iface
809 = do { showPass (hsc_dflags hsc_env)
810 ("Checking old interface for " ++ moduleUserString mod) ;
812 ; initIfaceCheck hsc_env $
813 check_old_iface mod iface_path source_unchanged maybe_iface
816 check_old_iface this_mod iface_path source_unchanged maybe_iface
817 = -- CHECK WHETHER THE SOURCE HAS CHANGED
818 ifM (not source_unchanged)
819 (traceHiDiffs (nest 4 (text "Source file changed or recompilation check turned off")))
822 -- If the source has changed and we're in interactive mode, avoid reading
823 -- an interface; just return the one we might have been supplied with.
824 getGhciMode `thenM` \ ghci_mode ->
825 if (ghci_mode == Interactive) && not source_unchanged then
826 returnM (outOfDate, maybe_iface)
829 case maybe_iface of {
830 Just old_iface -> -- Use the one we already have
831 checkVersions source_unchanged old_iface `thenM` \ recomp ->
832 returnM (recomp, Just old_iface)
836 -- Try and read the old interface for the current module
837 -- from the .hi file left from the last time we compiled it
838 readIface this_mod iface_path False `thenM` \ read_result ->
839 case read_result of {
840 Failed err -> -- Old interface file not found, or garbled; give up
841 traceIf (text "FYI: cannot read old interface file:"
842 $$ nest 4 err) `thenM_`
843 returnM (outOfDate, Nothing)
847 -- We have got the old iface; check its versions
848 checkVersions source_unchanged iface `thenM` \ recomp ->
849 returnM (recomp, Just iface)
853 @recompileRequired@ is called from the HscMain. It checks whether
854 a recompilation is required. It needs access to the persistent state,
855 finder, etc, because it may have to load lots of interface files to
856 check their versions.
859 type RecompileRequired = Bool
860 upToDate = False -- Recompile not required
861 outOfDate = True -- Recompile required
863 checkVersions :: Bool -- True <=> source unchanged
864 -> ModIface -- Old interface
865 -> IfG RecompileRequired
866 checkVersions source_unchanged iface
867 | not source_unchanged
870 = do { traceHiDiffs (text "Considering whether compilation is required for" <+>
871 ppr (mi_module iface) <> colon)
873 -- Source code unchanged and no errors yet... carry on
875 -- First put the dependent-module info, read from the old interface, into the envt,
876 -- so that when we look for interfaces we look for the right one (.hi or .hi-boot)
878 -- It's just temporary because either the usage check will succeed
879 -- (in which case we are done with this module) or it'll fail (in which
880 -- case we'll compile the module from scratch anyhow).
882 -- We do this regardless of compilation mode
883 ; updateEps_ $ \eps -> eps { eps_is_boot = mod_deps }
885 ; checkList [checkModUsage u | u <- mi_usages iface]
888 -- This is a bit of a hack really
889 mod_deps :: ModuleEnv (Module, IsBootInterface)
890 mod_deps = mkModDeps (dep_mods (mi_deps iface))
892 checkModUsage :: Usage -> IfG RecompileRequired
893 -- Given the usage information extracted from the old
894 -- M.hi file for the module being compiled, figure out
895 -- whether M needs to be recompiled.
897 checkModUsage (Usage { usg_name = mod_name, usg_mod = old_mod_vers,
898 usg_rules = old_rule_vers,
899 usg_exports = maybe_old_export_vers,
900 usg_entities = old_decl_vers })
901 = -- Load the imported interface is possible
903 doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
905 traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_`
907 loadInterface doc_str mod_name ImportBySystem `thenM` \ mb_iface ->
908 -- Load the interface, but don't complain on failure;
909 -- Instead, get an Either back which we can test
912 Failed exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"),
914 -- Couldn't find or parse a module mentioned in the
915 -- old interface file. Don't complain -- it might just be that
916 -- the current module doesn't need that import and it's been deleted
920 new_mod_vers = mi_mod_vers iface
921 new_decl_vers = mi_ver_fn iface
922 new_export_vers = mi_exp_vers iface
923 new_rule_vers = mi_rule_vers iface
926 checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile ->
927 if not recompile then
932 if checkExportList maybe_old_export_vers new_export_vers then
933 out_of_date_vers (ptext SLIT(" Export list changed"))
934 (fromJust maybe_old_export_vers)
939 if old_rule_vers /= new_rule_vers then
940 out_of_date_vers (ptext SLIT(" Rules changed"))
941 old_rule_vers new_rule_vers
944 -- CHECK ITEMS ONE BY ONE
945 checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile ->
947 returnM outOfDate -- This one failed, so just bail out now
949 up_to_date (ptext SLIT(" Great! The bits I use are up to date"))
952 ------------------------
953 checkModuleVersion old_mod_vers new_mod_vers
954 | new_mod_vers == old_mod_vers
955 = up_to_date (ptext SLIT("Module version unchanged"))
958 = out_of_date_vers (ptext SLIT(" Module version has changed"))
959 old_mod_vers new_mod_vers
961 ------------------------
962 checkExportList Nothing new_vers = upToDate
963 checkExportList (Just v) new_vers = v /= new_vers
965 ------------------------
966 checkEntityUsage new_vers (name,old_vers)
967 = case new_vers name of
969 Nothing -> -- We used it before, but it ain't there now
970 out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
972 Just new_vers -- It's there, but is it up to date?
973 | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_`
975 | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name)
978 up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate
979 out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate
980 out_of_date_vers msg old_vers new_vers
981 = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers])
983 ----------------------
984 checkList :: [IfG RecompileRequired] -> IfG RecompileRequired
985 -- This helper is used in two places
986 checkList [] = returnM upToDate
987 checkList (check:checks) = check `thenM` \ recompile ->
994 %************************************************************************
998 %************************************************************************
1001 showIface :: FilePath -> IO ()
1002 -- Raad binary interface, and print it out
1003 showIface filename = do
1004 -- skip the version check; we don't want to worry about profiled vs.
1005 -- non-profiled interfaces, for example.
1006 writeIORef v_IgnoreHiWay True
1007 iface <- Binary.getBinFileWithDict filename
1008 printDump (pprModIface iface)
1014 pprModIface :: ModIface -> SDoc
1017 = vcat [ ptext SLIT("interface")
1018 <+> ppr_package (mi_package iface)
1019 <+> ppr (mi_module iface) <+> ppr (mi_mod_vers iface)
1021 <+> (if mi_orphan iface then ptext SLIT("[orphan module]") else empty)
1022 <+> int opt_HiVersion
1023 <+> ptext SLIT("where")
1024 , vcat (map pprExport (mi_exports iface))
1025 , pprDeps (mi_deps iface)
1026 , vcat (map pprUsage (mi_usages iface))
1027 , pprFixities (mi_fixities iface)
1028 , vcat (map pprIfaceDecl (mi_decls iface))
1029 , vcat (map ppr (mi_insts iface))
1030 , vcat (map ppr (mi_rules iface))
1031 , pprDeprecs (mi_deprecs iface)
1034 ppr_package HomePackage = empty
1035 ppr_package (ExtPackage id) = doubleQuotes (ppr id)
1037 exp_vers = mi_exp_vers iface
1038 rule_vers = mi_rule_vers iface
1040 pp_sub_vers | exp_vers == initialVersion && rule_vers == initialVersion = empty
1041 | otherwise = brackets (ppr exp_vers <+> ppr rule_vers)
1044 When printing export lists, we print like this:
1046 AvailTC C [C, x, y] C(x,y)
1047 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
1050 pprExport :: IfaceExport -> SDoc
1051 pprExport (mod, items)
1052 = hsep [ ptext SLIT("export"), ppr mod, hsep (map pp_avail items) ]
1054 pp_avail :: GenAvailInfo OccName -> SDoc
1055 pp_avail (Avail occ) = ppr occ
1056 pp_avail (AvailTC _ []) = empty
1057 pp_avail (AvailTC n (n':ns))
1058 | n==n' = ppr n <> pp_export ns
1059 | otherwise = ppr n <> char '|' <> pp_export (n':ns)
1061 pp_export [] = empty
1062 pp_export names = braces (hsep (map ppr names))
1064 pprUsage :: Usage -> SDoc
1066 = hsep [ptext SLIT("import"), ppr (usg_name usage),
1067 int (usg_mod usage),
1068 pp_export_version (usg_exports usage),
1069 int (usg_rules usage),
1070 pp_versions (usg_entities usage) ]
1072 pp_versions nvs = hsep [ ppr n <+> int v | (n,v) <- nvs ]
1073 pp_export_version Nothing = empty
1074 pp_export_version (Just v) = int v
1076 pprDeps :: Dependencies -> SDoc
1077 pprDeps (Deps { dep_mods = mods, dep_pkgs = pkgs, dep_orphs = orphs})
1078 = vcat [ptext SLIT("module dependencies:") <+> fsep (map ppr_mod mods),
1079 ptext SLIT("package dependencies:") <+> fsep (map ppr pkgs),
1080 ptext SLIT("orphans:") <+> fsep (map ppr orphs)
1083 ppr_mod (mod_name, boot) = ppr mod_name <+> ppr_boot boot
1084 ppr_boot True = text "[boot]"
1085 ppr_boot False = empty
1087 pprIfaceDecl :: (Version, IfaceDecl) -> SDoc
1088 pprIfaceDecl (ver, decl)
1089 = ppr_vers ver <+> ppr decl
1091 -- Print the version for the decl
1092 ppr_vers v | v == initialVersion = empty
1095 pprFixities :: [(OccName, Fixity)] -> SDoc
1096 pprFixities [] = empty
1097 pprFixities fixes = ptext SLIT("fixities") <+> pprWithCommas pprFix fixes
1099 pprFix (occ,fix) = ppr fix <+> ppr occ
1101 pprDeprecs NoDeprecs = empty
1102 pprDeprecs (DeprecAll txt) = ptext SLIT("Deprecate all") <+> doubleQuotes (ftext txt)
1103 pprDeprecs (DeprecSome prs) = ptext SLIT("Deprecate") <+> vcat (map pprDeprec prs)
1105 pprDeprec (name, txt) = ppr name <+> doubleQuotes (ftext txt)