2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
7 pprModIface, 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 writeIfaceFile, -- Write the interface file
16 checkOldIface -- See if recompilation is required, by
17 -- comparing version information
21 -----------------------------------------------
22 MkIface.lhs deals with versioning
23 -----------------------------------------------
25 Here's the version-related info in an interface file
27 module Foo 8 -- module-version
28 3 -- export-list-version
30 Usages: -- Version info for what this compilation of Foo imported
31 Baz 3 -- Module version
32 [4] -- The export-list version if Foo depended on it
33 (g,2) -- Function and its version
34 (T,1) -- Type and its version
36 <version> f :: Int -> Int {- Unfolding: \x -> Wib.t[2] x -}
37 -- The [2] says that f's unfolding
38 -- mentions verison 2 of Wib.t
40 -----------------------------------------------
42 -----------------------------------------------
45 * In the mi_usages information in an interface, we record the
46 version number of each free variable of the module
48 * In mkIface, we compute the version number of each exported thing A.f
49 by comparing its A.f's info with its new info, and bumping its
50 version number if it differs. If A.f mentions B.g, and B.g's version
51 number has changed, then we count A.f as having changed too.
53 * In checkOldIface we compare the mi_usages for the module with
54 the actual version info for all each thing recorded in mi_usages
59 We count A.f as changing if its fixity changes
63 If a rule changes, we want to recompile any module that might be
64 affected by that rule. For non-orphan rules, this is relatively easy.
65 If module M defines f, and a rule for f, just arrange that the version
66 number for M.f changes if any of the rules for M.f change. Any module
67 that does not depend on M.f can't be affected by the rule-change
70 Orphan rules (ones whose 'head function' is not defined in M) are
71 harder. Here's what we do.
73 * We have a per-module orphan-rule version number which changes if
74 any orphan rule changes. (It's unaffected by non-orphan rules.)
76 * We record usage info for any orphan module 'below' this one,
77 giving the orphan-rule version number. We recompile if this
80 The net effect is that if an orphan rule changes, we recompile every
81 module above it. That's very conservative, but it's devilishly hard
82 to know what it might affect, so we just have to be conservative.
86 In an iface file we have
88 instance Eq a => Eq [a] = dfun29
91 We have a version number for dfun29, covering its unfolding
92 etc. Suppose we are compiling a module M that imports A only
93 indirectly. If typechecking M uses this instance decl, we record the
94 dependency on A.dfun29 as if it were a free variable of the module
95 (via the tcg_inst_usages accumulator). That means that A will appear
96 in M's usage list. If the shape of the instance declaration changes,
97 then so will dfun29's version, triggering a recompilation.
99 Adding an instance declaration, or changing an instance decl that is
100 not currently used, is more tricky. (This really only makes a
101 difference when we have overlapping instance decls, because then the
102 new instance decl might kick in to override the old one.) We handle
103 this in a very similar way that we handle rules above.
105 * For non-orphan instance decls, identify one locally-defined tycon/class
106 mentioned in the decl. Treat the instance decl as part of the defn of that
107 tycon/class, so that if the shape of the instance decl changes, so does the
108 tycon/class; that in turn will force recompilation of anything that uses
111 * For orphan instance decls, act the same way as for orphan rules.
112 Indeed, we use the same global orphan-rule version number.
116 mkUsageInfo figures out what the ``usage information'' for this
117 moudule is; that is, what it must record in its interface file as the
120 We produce a line for every module B below the module, A, currently being
123 to record the fact that A does import B indirectly. This is used to decide
124 to look to look for B.hi rather than B.hi-boot when compiling a module that
125 imports A. This line says that A imports B, but uses nothing in it.
126 So we'll get an early bale-out when compiling A if B's version changes.
128 The usage information records:
131 \item (a) anything reachable from its body code
132 \item (b) any module exported with a @module Foo@
133 \item (c) anything reachable from an exported item
136 Why (b)? Because if @Foo@ changes then this module's export list
137 will change, so we must recompile this module at least as far as
138 making a new interface file --- but in practice that means complete
141 Why (c)? Consider this:
143 module A( f, g ) where | module B( f ) where
144 import B( f ) | f = h 3
148 Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in
149 @A@'s usages? Our idea is that we aren't going to touch A.hi if it is
150 *identical* to what it was before. If anything about @B.f@ changes
151 than anyone who imports @A@ should be recompiled in case they use
152 @B.f@ (they'll get an early exit if they don't). So, if anything
153 about @B.f@ changes we'd better make sure that something in A.hi
154 changes, and the convenient way to do that is to record the version
155 number @B.f@ in A.hi in the usage list. If B.f changes that'll force a
156 complete recompiation of A, which is overkill but it's the only way to
157 write a new, slightly different, A.hi.
159 But the example is tricker. Even if @B.f@ doesn't change at all,
160 @B.h@ may do so, and this change may not be reflected in @f@'s version
161 number. But with -O, a module that imports A must be recompiled if
162 @B.h@ changes! So A must record a dependency on @B.h@. So we treat
163 the occurrence of @B.f@ in the export list *just as if* it were in the
164 code of A, and thereby haul in all the stuff reachable from it.
166 *** Conclusion: if A mentions B.f in its export list,
167 behave just as if A mentioned B.f in its source code,
168 and slurp in B.f and all its transitive closure ***
170 [NB: If B was compiled with -O, but A isn't, we should really *still*
171 haul in all the unfoldings for B, in case the module that imports A *is*
172 compiled with -O. I think this is the case.]
176 #include "HsVersions.h"
179 import Packages ( isHomeModule, PackageIdH(..) )
180 import IfaceSyn ( IfaceDecl(..), IfaceClassOp(..), IfaceConDecl(..),
181 IfaceRule(..), IfaceInst(..), IfaceExtName(..),
182 eqIfDecl, eqIfRule, eqIfInst, IfaceEq(..), (&&&), bool,
183 eqMaybeBy, eqListBy, visibleIfConDecls,
184 tyThingToIfaceDecl, instanceToIfaceInst, coreRuleToIfaceRule )
185 import LoadIface ( readIface, loadInterface )
186 import BasicTypes ( Version, initialVersion, bumpVersion )
188 import TcRnTypes ( mkModDeps )
189 import HscTypes ( ModIface(..), ModDetails(..),
190 ModGuts(..), IfaceExport,
191 HscEnv(..), hscEPS, Dependencies(..), FixItem(..),
192 ModSummary(..), msHiFilePath,
193 mkIfaceDepCache, mkIfaceFixCache, mkIfaceVerCache,
195 GenAvailInfo(..), availName,
196 ExternalPackageState(..),
197 Usage(..), IsBootInterface,
198 Deprecs(..), IfaceDeprecs, Deprecations,
203 import Packages ( HomeModules )
204 import DynFlags ( GhcMode(..), DynFlags(..), DynFlag(..), dopt )
205 import StaticFlags ( opt_HiVersion )
206 import Name ( Name, nameModule, nameOccName, nameParent,
207 isExternalName, isInternalName, nameParent_maybe, isWiredInName,
208 isImplicitName, NamedThing(..) )
211 import OccName ( OccName, OccEnv, mkOccEnv, lookupOccEnv, emptyOccEnv,
213 OccSet, emptyOccSet, elemOccSet, occSetElts,
214 extendOccSet, extendOccSetList,
215 isEmptyOccSet, intersectOccSet, intersectsOccSet,
217 import Module ( Module, moduleFS,
218 ModLocation(..), mkSysModuleFS, moduleUserString,
219 ModuleEnv, emptyModuleEnv, lookupModuleEnv,
223 import Util ( 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 %************************************************************************
251 -> Maybe ModIface -- The old interface, if we have it
252 -> ModGuts -- Usages, deprecations, etc
253 -> ModDetails -- The trimmed, tidied interface
254 -> IO (ModIface, -- The new one, complete with decls and versions
255 Bool) -- True <=> there was an old Iface, and the new one
256 -- is identical, so no need to write it
258 mkIface hsc_env maybe_old_iface
259 (ModGuts{ mg_module = this_mod,
263 mg_home_mods = home_mods,
264 mg_rdr_env = rdr_env,
265 mg_fix_env = fix_env,
266 mg_deprecs = src_deprecs })
267 (ModDetails{ md_insts = insts,
270 md_exports = exports })
272 -- NB: notice that mkIface does not look at the bindings
273 -- only at the TypeEnv. The previous Tidy phase has
274 -- put exactly the info into the TypeEnv that we want
275 -- to expose in the interface
277 = do { eps <- hscEPS hsc_env
278 ; let { ext_nm_rhs = mkExtNameFn hsc_env home_mods eps this_mod
279 ; ext_nm_lhs = mkLhsNameFn this_mod
281 ; decls = [ tyThingToIfaceDecl ext_nm_rhs thing
282 | thing <- typeEnvElts type_env,
283 not (isImplicitName (getName thing)) ]
284 -- Don't put implicit Ids and class tycons in the interface file
286 ; fixities = [(occ,fix) | FixItem occ fix _ <- nameEnvElts fix_env]
287 ; deprecs = mkIfaceDeprec src_deprecs
288 ; iface_rules = map (coreRuleToIfaceRule ext_nm_lhs ext_nm_rhs) rules
289 ; iface_insts = map (instanceToIfaceInst ext_nm_lhs) insts
291 ; intermediate_iface = ModIface {
292 mi_module = this_mod,
293 mi_package = HomePackage,
297 mi_exports = mkIfaceExports exports,
298 mi_insts = sortLe le_inst iface_insts,
299 mi_rules = sortLe le_rule iface_rules,
300 mi_fixities = fixities,
301 mi_deprecs = deprecs,
302 mi_globals = Just rdr_env,
304 -- Left out deliberately: filled in by addVersionInfo
305 mi_mod_vers = initialVersion,
306 mi_exp_vers = initialVersion,
307 mi_rule_vers = initialVersion,
308 mi_orphan = False, -- Always set by addVersionInfo, but
309 -- it's a strict field, so we can't omit it.
310 mi_decls = deliberatelyOmitted "decls",
311 mi_ver_fn = deliberatelyOmitted "ver_fn",
313 -- And build the cached values
314 mi_dep_fn = mkIfaceDepCache deprecs,
315 mi_fix_fn = mkIfaceFixCache fixities }
317 -- Add version information
318 ; (new_iface, no_change_at_all, pp_diffs, pp_orphs)
319 = _scc_ "versioninfo"
320 addVersionInfo maybe_old_iface intermediate_iface decls
324 ; when (isJust pp_orphs && dopt Opt_WarnOrphans dflags)
325 (printDump (fromJust pp_orphs))
326 ; when (dopt Opt_D_dump_hi_diffs dflags) (printDump pp_diffs)
327 ; dumpIfSet_dyn dflags Opt_D_dump_hi "FINAL INTERFACE"
328 (pprModIface new_iface)
330 ; return (new_iface, no_change_at_all) }
332 r1 `le_rule` r2 = ifRuleName r1 <= ifRuleName r2
333 i1 `le_inst` i2 = ifDFun i1 <= ifDFun i2
335 dflags = hsc_dflags hsc_env
336 deliberatelyOmitted x = panic ("Deliberately omitted: " ++ x)
339 -----------------------------
340 writeIfaceFile :: HscEnv -> ModLocation -> ModIface -> Bool -> IO ()
341 -- Write the interface file, if necessary
342 writeIfaceFile hsc_env location new_iface no_change_at_all
343 | no_change_at_all = return ()
344 | ghc_mode == Interactive = return ()
345 | ghc_mode == JustTypecheck = return ()
347 = do { createDirectoryHierarchy (directoryOf hi_file_path)
348 ; writeBinIface hi_file_path new_iface }
350 ghc_mode = ghcMode (hsc_dflags hsc_env)
351 hi_file_path = ml_hi_file location
354 -----------------------------
355 mkExtNameFn :: HscEnv -> HomeModules -> ExternalPackageState -> Module -> Name -> IfaceExtName
356 mkExtNameFn hsc_env hmods eps this_mod
359 hpt = hsc_HPT hsc_env
363 | mod == this_mod = case nameParent_maybe name of
364 Nothing -> LocalTop occ
365 Just par -> LocalTopSub occ (nameOccName par)
366 | isWiredInName name = ExtPkg mod occ
367 | isHomeModule hmods mod = HomePkg mod occ vers
368 | otherwise = ExtPkg mod occ
370 mod = nameModule name
371 occ = nameOccName name
372 par_occ = nameOccName (nameParent name)
373 -- The version of the *parent* is the one want
374 vers = lookupVersion mod par_occ
376 lookupVersion :: Module -> OccName -> Version
377 -- Even though we're looking up a home-package thing, in
378 -- one-shot mode the imported interfaces may be in the PIT
379 lookupVersion mod occ
380 = mi_ver_fn iface occ `orElse`
381 pprPanic "lookupVers1" (ppr mod <+> ppr occ)
383 iface = lookupIfaceByModule hpt pit mod `orElse`
384 pprPanic "lookupVers2" (ppr mod <+> ppr occ)
387 ---------------------
388 -- mkLhsNameFn ignores versioning info altogether
389 -- It is used for the LHS of instance decls and rules, where we
390 -- there's no point in recording version info
391 mkLhsNameFn :: Module -> Name -> IfaceExtName
392 mkLhsNameFn this_mod name
393 | isInternalName name = pprTrace "mkLhsNameFn: unexpected internal" (ppr name) $
394 LocalTop occ -- Should not happen
395 | mod == this_mod = LocalTop occ
396 | otherwise = ExtPkg mod occ
398 mod = nameModule name
399 occ = nameOccName name
402 -----------------------------
403 -- Compute version numbers for local decls
405 addVersionInfo :: Maybe ModIface -- The old interface, read from M.hi
406 -> ModIface -- The new interface decls (lacking decls)
407 -> [IfaceDecl] -- The new decls
409 Bool, -- True <=> no changes at all; no need to write new Iface
411 Maybe SDoc) -- Warnings about orphans
413 addVersionInfo Nothing new_iface new_decls
414 -- No old interface, so definitely write a new one!
415 = (new_iface { mi_orphan = anyNothing ifInstOrph (mi_insts new_iface)
416 || anyNothing ifRuleOrph (mi_rules new_iface),
417 mi_decls = [(initialVersion, decl) | decl <- new_decls],
418 mi_ver_fn = \n -> Just initialVersion },
420 ptext SLIT("No old interface file"),
421 pprOrphans orph_insts orph_rules)
423 orph_insts = filter (isNothing . ifInstOrph) (mi_insts new_iface)
424 orph_rules = filter (isNothing . ifRuleOrph) (mi_rules new_iface)
426 addVersionInfo (Just old_iface@(ModIface { mi_mod_vers = old_mod_vers,
427 mi_exp_vers = old_exp_vers,
428 mi_rule_vers = old_rule_vers,
429 mi_decls = old_decls,
430 mi_ver_fn = old_decl_vers,
431 mi_fix_fn = old_fixities }))
432 new_iface@(ModIface { mi_fix_fn = new_fixities })
435 | no_change_at_all = (old_iface, True, ptext SLIT("Interface file unchanged"), pp_orphs)
436 | otherwise = (final_iface, False, vcat [ptext SLIT("Interface file has changed"),
437 nest 2 pp_diffs], pp_orphs)
439 final_iface = new_iface { mi_mod_vers = bump_unless no_output_change old_mod_vers,
440 mi_exp_vers = bump_unless no_export_change old_exp_vers,
441 mi_rule_vers = bump_unless no_rule_change old_rule_vers,
442 mi_orphan = not (null new_orph_rules && null new_orph_insts),
443 mi_decls = decls_w_vers,
444 mi_ver_fn = mkIfaceVerCache decls_w_vers }
446 decls_w_vers = [(add_vers decl, decl) | decl <- new_decls]
449 (old_non_orph_insts, old_orph_insts) = mkOrphMap ifInstOrph (mi_insts old_iface)
450 (new_non_orph_insts, new_orph_insts) = mkOrphMap ifInstOrph (mi_insts new_iface)
451 same_insts occ = eqMaybeBy (eqListBy eqIfInst)
452 (lookupOccEnv old_non_orph_insts occ)
453 (lookupOccEnv new_non_orph_insts occ)
455 (old_non_orph_rules, old_orph_rules) = mkOrphMap ifRuleOrph (mi_rules old_iface)
456 (new_non_orph_rules, new_orph_rules) = mkOrphMap ifRuleOrph (mi_rules new_iface)
457 same_rules occ = eqMaybeBy (eqListBy eqIfRule)
458 (lookupOccEnv old_non_orph_rules occ)
459 (lookupOccEnv new_non_orph_rules occ)
461 -- Computing what changed
462 no_output_change = no_decl_change && no_rule_change &&
463 no_export_change && no_deprec_change
464 no_export_change = mi_exports new_iface == mi_exports old_iface -- Kept sorted
465 no_decl_change = isEmptyOccSet changed_occs
466 no_rule_change = not (changedWrt changed_occs (eqListBy eqIfRule old_orph_rules new_orph_rules)
467 || changedWrt changed_occs (eqListBy eqIfInst old_orph_insts new_orph_insts))
468 no_deprec_change = mi_deprecs new_iface == mi_deprecs old_iface
470 -- If the usages havn't changed either, we don't need to write the interface file
471 no_other_changes = mi_usages new_iface == mi_usages old_iface &&
472 mi_deps new_iface == mi_deps old_iface
473 no_change_at_all = no_output_change && no_other_changes
475 pp_diffs = vcat [pp_change no_export_change "Export list"
476 (ppr old_exp_vers <+> arrow <+> ppr (mi_exp_vers final_iface)),
477 pp_change no_rule_change "Rules"
478 (ppr old_rule_vers <+> arrow <+> ppr (mi_rule_vers final_iface)),
479 pp_change no_deprec_change "Deprecations" empty,
480 pp_change no_other_changes "Usages" empty,
482 pp_change True what info = empty
483 pp_change False what info = text what <+> ptext SLIT("changed") <+> info
486 old_decl_env = mkOccEnv [(ifName decl, decl) | (_,decl) <- old_decls]
487 same_fixity n = bool (old_fixities n == new_fixities n)
490 -- Adding version info
491 new_version = bumpVersion old_mod_vers
492 add_vers decl | occ `elemOccSet` changed_occs = new_version
493 | otherwise = expectJust "add_vers" (old_decl_vers occ)
494 -- If it's unchanged, there jolly well
495 where -- should be an old version number
499 changed_occs :: OccSet
500 changed_occs = computeChangedOccs eq_info
502 eq_info :: [(OccName, IfaceEq)]
503 eq_info = map check_eq new_decls
504 check_eq new_decl | Just old_decl <- lookupOccEnv old_decl_env occ
505 = (occ, new_decl `eqIfDecl` old_decl &&&
506 eq_indirects new_decl)
507 | otherwise {- No corresponding old decl -}
510 occ = ifName new_decl
512 eq_indirects :: IfaceDecl -> IfaceEq
513 -- When seeing if two decls are the same, remember to
514 -- check whether any relevant fixity or rules have changed
515 eq_indirects (IfaceId {ifName = occ}) = eq_ind_occ occ
516 eq_indirects (IfaceClass {ifName = cls_occ, ifSigs = sigs})
517 = same_insts cls_occ &&&
518 eq_ind_occs [op | IfaceClassOp op _ _ <- sigs]
519 eq_indirects (IfaceData {ifName = tc_occ, ifCons = cons})
520 = same_insts tc_occ &&& same_fixity tc_occ &&& -- The TyCon can have a fixity too
521 eq_ind_occs (map ifConOcc (visibleIfConDecls cons))
522 eq_indirects other = Equal -- Synonyms and foreign declarations
524 eq_ind_occ :: OccName -> IfaceEq -- For class ops and Ids; check fixity and rules
525 eq_ind_occ occ = same_fixity occ &&& same_rules occ
526 eq_ind_occs = foldr ((&&&) . eq_ind_occ) Equal
530 pp_decl_diffs :: SDoc -- Nothing => no changes
532 | isEmptyOccSet changed_occs = empty
534 = vcat [ptext SLIT("Changed occs:") <+> ppr (occSetElts changed_occs),
535 ptext SLIT("Version change for these decls:"),
536 nest 2 (vcat (map show_change new_decls))]
538 eq_env = mkOccEnv eq_info
540 | not (occ `elemOccSet` changed_occs) = empty
542 = vcat [ppr occ <+> ppr (old_decl_vers occ) <+> arrow <+> ppr new_version,
545 occ = ifName new_decl
546 why = case lookupOccEnv eq_env occ of
547 Just (EqBut occs) -> sep [ppr occ <> colon, ptext SLIT("Free vars (only) changed:"),
548 nest 2 (braces (fsep (map ppr (occSetElts
549 (occs `intersectOccSet` changed_occs)))))]
551 | Just old_decl <- lookupOccEnv old_decl_env occ
552 -> vcat [ptext SLIT("Old:") <+> ppr old_decl,
553 ptext SLIT("New:") <+> ppr new_decl]
555 -> ppr occ <+> ptext SLIT("only in new interface")
556 other -> pprPanic "MkIface.show_change" (ppr occ)
558 pp_orphs = pprOrphans new_orph_insts new_orph_rules
560 pprOrphans insts rules
561 | null insts && null rules = Nothing
564 if null insts then empty else
565 hang (ptext SLIT("Warning: orphan instances:"))
566 2 (vcat (map ppr insts)),
567 if null rules then empty else
568 hang (ptext SLIT("Warning: orphan rules:"))
569 2 (vcat (map ppr rules))
572 computeChangedOccs :: [(OccName, IfaceEq)] -> OccSet
573 computeChangedOccs eq_info
574 = foldl add_changes emptyOccSet (stronglyConnComp edges)
576 edges :: [((OccName,IfaceEq), Unique, [Unique])]
577 edges = [ (node, getUnique occ, map getUnique occs)
578 | node@(occ, iface_eq) <- eq_info
579 , let occs = case iface_eq of
580 EqBut occ_set -> occSetElts occ_set
583 -- Changes in declarations
584 add_changes :: OccSet -> SCC (OccName, IfaceEq) -> OccSet
585 add_changes so_far (AcyclicSCC (occ, iface_eq))
586 | changedWrt so_far iface_eq -- This one has changed
587 = extendOccSet so_far occ
588 add_changes so_far (CyclicSCC pairs)
589 | changedWrt so_far (foldr1 (&&&) (map snd pairs)) -- One of this group has changed
590 = extendOccSetList so_far (map fst pairs)
591 add_changes so_far other = so_far
593 changedWrt :: OccSet -> IfaceEq -> Bool
594 changedWrt so_far Equal = False
595 changedWrt so_far NotEqual = True
596 changedWrt so_far (EqBut kids) = so_far `intersectsOccSet` kids
598 ----------------------
599 -- mkOrphMap partitions instance decls or rules into
600 -- (a) an OccEnv for ones that are not orphans,
601 -- mapping the local OccName to a list of its decls
602 -- (b) a list of orphan decls
603 mkOrphMap :: (decl -> Maybe OccName) -- (Just occ) for a non-orphan decl, keyed by occ
604 -- Nothing for an orphan decl
605 -> [decl] -- Sorted into canonical order
606 -> (OccEnv [decl], -- Non-orphan decls associated with their key;
607 -- each sublist in canonical order
608 [decl]) -- Orphan decls; in canonical order
609 mkOrphMap get_key decls
610 = foldl go (emptyOccEnv, []) decls
612 go (non_orphs, orphs) d
613 | Just occ <- get_key d
614 = (extendOccEnv_C (\ ds _ -> d:ds) non_orphs occ [d], orphs)
615 | otherwise = (non_orphs, d:orphs)
617 anyNothing :: (a -> Maybe b) -> [a] -> Bool
618 anyNothing p [] = False
619 anyNothing p (x:xs) = isNothing (p x) || anyNothing p xs
621 ----------------------
622 mkIfaceDeprec :: Deprecations -> IfaceDeprecs
623 mkIfaceDeprec NoDeprecs = NoDeprecs
624 mkIfaceDeprec (DeprecAll t) = DeprecAll t
625 mkIfaceDeprec (DeprecSome env) = DeprecSome (sortLe (<=) (nameEnvElts env))
627 ----------------------
628 bump_unless :: Bool -> Version -> Version
629 bump_unless True v = v -- True <=> no change
630 bump_unless False v = bumpVersion v
634 %*********************************************************
636 \subsection{Keeping track of what we've slurped, and version numbers}
638 %*********************************************************
642 mkUsageInfo :: HscEnv
644 -> ModuleEnv (Module, Maybe Bool, SrcSpan)
645 -> [(Module, IsBootInterface)]
646 -> NameSet -> IO [Usage]
647 mkUsageInfo hsc_env hmods dir_imp_mods dep_mods used_names
648 = do { eps <- hscEPS hsc_env
649 ; let usages = mk_usage_info (eps_PIT eps) hsc_env hmods
650 dir_imp_mods dep_mods used_names
651 ; usages `seqList` return usages }
652 -- seq the list of Usages returned: occasionally these
653 -- don't get evaluated for a while and we can end up hanging on to
654 -- the entire collection of Ifaces.
656 mk_usage_info pit hsc_env hmods dir_imp_mods dep_mods proto_used_names
657 = mapCatMaybes mkUsage dep_mods
658 -- ToDo: do we need to sort into canonical order?
660 hpt = hsc_HPT hsc_env
662 used_names = mkNameSet $ -- Eliminate duplicates
663 [ nameParent n -- Just record usage on the 'main' names
664 | n <- nameSetToList proto_used_names
665 , not (isWiredInName n) -- Don't record usages for wired-in names
666 , isExternalName n -- Ignore internal names
669 -- ent_map groups together all the things imported and used
670 -- from a particular module in this package
671 ent_map :: ModuleEnv [OccName]
672 ent_map = foldNameSet add_mv emptyModuleEnv used_names
673 add_mv name mv_map = extendModuleEnv_C add_item mv_map mod [occ]
675 occ = nameOccName name
676 mod = nameModule name
677 add_item occs _ = occ:occs
679 import_all mod = case lookupModuleEnv dir_imp_mods mod of
680 Just (_,imp_all,_) -> isNothing imp_all
683 -- We want to create a Usage for a home module if
684 -- a) we used something from; has something in used_names
685 -- b) we imported all of it, even if we used nothing from it
686 -- (need to recompile if its export list changes: export_vers)
687 -- c) is a home-package orphan module (need to recompile if its
688 -- instance decls change: rules_vers)
689 mkUsage :: (Module, Bool) -> Maybe Usage
690 mkUsage (mod_name, _)
691 | isNothing maybe_iface -- We can't depend on it if we didn't
692 || not (isHomeModule hmods mod) -- even open the interface!
696 = Nothing -- Record no usage info
699 = Just (Usage { usg_name = mod,
701 usg_exports = export_vers,
702 usg_entities = ent_vers,
703 usg_rules = rules_vers })
705 maybe_iface = lookupIfaceByModule hpt pit mod_name
706 -- In one-shot mode, the interfaces for home-package
707 -- modules accumulate in the PIT not HPT. Sigh.
709 Just iface = maybe_iface
710 mod = mi_module iface
711 orphan_mod = mi_orphan iface
712 version_env = mi_ver_fn iface
713 mod_vers = mi_mod_vers iface
714 rules_vers = mi_rule_vers iface
715 all_imported = import_all mod
716 export_vers | all_imported = Just (mi_exp_vers iface)
717 | otherwise = Nothing
719 -- The sort is to put them into canonical order
720 used_occs = lookupModuleEnv ent_map mod `orElse` []
721 ent_vers :: [(OccName,Version)]
722 ent_vers = [ (occ, version_env occ `orElse` initialVersion)
723 | occ <- sortLe (<=) used_occs]
727 mkIfaceExports :: NameSet -> [(Module, [GenAvailInfo OccName])]
728 -- Group by module and sort by occurrence
729 -- This keeps the list in canonical order
730 mkIfaceExports exports
731 = [ (mkSysModuleFS fs, eltsFM avails)
732 | (fs, avails) <- fmToList groupFM
735 groupFM :: FiniteMap FastString (FiniteMap FastString (GenAvailInfo OccName))
736 -- Deliberately use the FastString so we
737 -- get a canonical ordering
738 groupFM = foldl add emptyFM (nameSetToList exports)
740 add env name = addToFM_C add_avail env mod_fs
741 (unitFM avail_fs avail)
743 occ = nameOccName name
744 mod_fs = moduleFS (nameModule name)
745 avail | Just p <- nameParent_maybe name = AvailTC (nameOccName p) [occ]
746 | isTcOcc occ = AvailTC occ [occ]
747 | otherwise = Avail occ
748 avail_fs = occNameFS (availName avail)
749 add_avail avail_fm _ = addToFM_C add_item avail_fm avail_fs avail
751 add_item (AvailTC p occs) _ = AvailTC p (List.insert occ occs)
752 add_item (Avail n) _ = pprPanic "MkIface.addAvail" (ppr n <+> ppr name)
756 %************************************************************************
758 Load the old interface file for this module (unless
759 we have it aleady), and check whether it is up to date
762 %************************************************************************
765 checkOldIface :: HscEnv
767 -> Bool -- Source unchanged
768 -> Maybe ModIface -- Old interface from compilation manager, if any
769 -> IO (RecompileRequired, Maybe ModIface)
771 checkOldIface hsc_env mod_summary source_unchanged maybe_iface
772 = do { showPass (hsc_dflags hsc_env)
773 ("Checking old interface for " ++ moduleUserString (ms_mod mod_summary)) ;
775 ; initIfaceCheck hsc_env $
776 check_old_iface mod_summary source_unchanged maybe_iface
779 check_old_iface mod_summary source_unchanged maybe_iface
780 = -- CHECK WHETHER THE SOURCE HAS CHANGED
781 ifM (not source_unchanged)
782 (traceHiDiffs (nest 4 (text "Source file changed or recompilation check turned off")))
785 -- If the source has changed and we're in interactive mode, avoid reading
786 -- an interface; just return the one we might have been supplied with.
787 getGhciMode `thenM` \ ghci_mode ->
788 if (ghci_mode == Interactive || ghci_mode == JustTypecheck)
789 && not source_unchanged then
790 returnM (outOfDate, maybe_iface)
793 case maybe_iface of {
794 Just old_iface -> -- Use the one we already have
795 checkVersions source_unchanged old_iface `thenM` \ recomp ->
796 returnM (recomp, Just old_iface)
800 -- Try and read the old interface for the current module
801 -- from the .hi file left from the last time we compiled it
803 iface_path = msHiFilePath mod_summary
805 readIface (ms_mod mod_summary) iface_path False `thenM` \ read_result ->
806 case read_result of {
807 Failed err -> -- Old interface file not found, or garbled; give up
808 traceIf (text "FYI: cannot read old interface file:"
809 $$ nest 4 err) `thenM_`
810 returnM (outOfDate, Nothing)
814 -- We have got the old iface; check its versions
815 checkVersions source_unchanged iface `thenM` \ recomp ->
816 returnM (recomp, Just iface)
820 @recompileRequired@ is called from the HscMain. It checks whether
821 a recompilation is required. It needs access to the persistent state,
822 finder, etc, because it may have to load lots of interface files to
823 check their versions.
826 type RecompileRequired = Bool
827 upToDate = False -- Recompile not required
828 outOfDate = True -- Recompile required
830 checkVersions :: Bool -- True <=> source unchanged
831 -> ModIface -- Old interface
832 -> IfG RecompileRequired
833 checkVersions source_unchanged iface
834 | not source_unchanged
837 = do { traceHiDiffs (text "Considering whether compilation is required for" <+>
838 ppr (mi_module iface) <> colon)
840 -- Source code unchanged and no errors yet... carry on
842 -- First put the dependent-module info, read from the old interface, into the envt,
843 -- so that when we look for interfaces we look for the right one (.hi or .hi-boot)
845 -- It's just temporary because either the usage check will succeed
846 -- (in which case we are done with this module) or it'll fail (in which
847 -- case we'll compile the module from scratch anyhow).
849 -- We do this regardless of compilation mode
850 ; updateEps_ $ \eps -> eps { eps_is_boot = mod_deps }
852 ; checkList [checkModUsage u | u <- mi_usages iface]
855 -- This is a bit of a hack really
856 mod_deps :: ModuleEnv (Module, IsBootInterface)
857 mod_deps = mkModDeps (dep_mods (mi_deps iface))
859 checkModUsage :: Usage -> IfG RecompileRequired
860 -- Given the usage information extracted from the old
861 -- M.hi file for the module being compiled, figure out
862 -- whether M needs to be recompiled.
864 checkModUsage (Usage { usg_name = mod_name, usg_mod = old_mod_vers,
865 usg_rules = old_rule_vers,
866 usg_exports = maybe_old_export_vers,
867 usg_entities = old_decl_vers })
868 = -- Load the imported interface is possible
870 doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
872 traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_`
874 loadInterface doc_str mod_name ImportBySystem `thenM` \ mb_iface ->
875 -- Load the interface, but don't complain on failure;
876 -- Instead, get an Either back which we can test
879 Failed exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"),
881 -- Couldn't find or parse a module mentioned in the
882 -- old interface file. Don't complain -- it might just be that
883 -- the current module doesn't need that import and it's been deleted
887 new_mod_vers = mi_mod_vers iface
888 new_decl_vers = mi_ver_fn iface
889 new_export_vers = mi_exp_vers iface
890 new_rule_vers = mi_rule_vers iface
893 checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile ->
894 if not recompile then
899 if checkExportList maybe_old_export_vers new_export_vers then
900 out_of_date_vers (ptext SLIT(" Export list changed"))
901 (fromJust maybe_old_export_vers)
906 if old_rule_vers /= new_rule_vers then
907 out_of_date_vers (ptext SLIT(" Rules changed"))
908 old_rule_vers new_rule_vers
911 -- CHECK ITEMS ONE BY ONE
912 checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile ->
914 returnM outOfDate -- This one failed, so just bail out now
916 up_to_date (ptext SLIT(" Great! The bits I use are up to date"))
919 ------------------------
920 checkModuleVersion old_mod_vers new_mod_vers
921 | new_mod_vers == old_mod_vers
922 = up_to_date (ptext SLIT("Module version unchanged"))
925 = out_of_date_vers (ptext SLIT(" Module version has changed"))
926 old_mod_vers new_mod_vers
928 ------------------------
929 checkExportList Nothing new_vers = upToDate
930 checkExportList (Just v) new_vers = v /= new_vers
932 ------------------------
933 checkEntityUsage new_vers (name,old_vers)
934 = case new_vers name of
936 Nothing -> -- We used it before, but it ain't there now
937 out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
939 Just new_vers -- It's there, but is it up to date?
940 | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_`
942 | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name)
945 up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate
946 out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate
947 out_of_date_vers msg old_vers new_vers
948 = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers])
950 ----------------------
951 checkList :: [IfG RecompileRequired] -> IfG RecompileRequired
952 -- This helper is used in two places
953 checkList [] = returnM upToDate
954 checkList (check:checks) = check `thenM` \ recompile ->
961 %************************************************************************
965 %************************************************************************
968 showIface :: FilePath -> IO ()
969 -- Read binary interface, and print it out
970 showIface filename = do
971 -- skip the version check; we don't want to worry about profiled vs.
972 -- non-profiled interfaces, for example.
973 writeIORef v_IgnoreHiWay True
974 iface <- Binary.getBinFileWithDict filename
975 printDump (pprModIface iface)
981 pprModIface :: ModIface -> SDoc
984 = vcat [ ptext SLIT("interface")
985 <+> ppr_package (mi_package iface)
986 <+> ppr (mi_module iface) <+> pp_boot
987 <+> ppr (mi_mod_vers iface) <+> pp_sub_vers
988 <+> (if mi_orphan iface then ptext SLIT("[orphan module]") else empty)
989 <+> int opt_HiVersion
990 <+> ptext SLIT("where")
991 , vcat (map pprExport (mi_exports iface))
992 , pprDeps (mi_deps iface)
993 , vcat (map pprUsage (mi_usages iface))
994 , pprFixities (mi_fixities iface)
995 , vcat (map pprIfaceDecl (mi_decls iface))
996 , vcat (map ppr (mi_insts iface))
997 , vcat (map ppr (mi_rules iface))
998 , pprDeprecs (mi_deprecs iface)
1001 pp_boot | mi_boot iface = ptext SLIT("[boot]")
1003 ppr_package HomePackage = empty
1004 ppr_package (ExtPackage id) = doubleQuotes (ppr id)
1006 exp_vers = mi_exp_vers iface
1007 rule_vers = mi_rule_vers iface
1009 pp_sub_vers | exp_vers == initialVersion && rule_vers == initialVersion = empty
1010 | otherwise = brackets (ppr exp_vers <+> ppr rule_vers)
1013 When printing export lists, we print like this:
1015 AvailTC C [C, x, y] C(x,y)
1016 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
1019 pprExport :: IfaceExport -> SDoc
1020 pprExport (mod, items)
1021 = hsep [ ptext SLIT("export"), ppr mod, hsep (map pp_avail items) ]
1023 pp_avail :: GenAvailInfo OccName -> SDoc
1024 pp_avail (Avail occ) = ppr occ
1025 pp_avail (AvailTC _ []) = empty
1026 pp_avail (AvailTC n (n':ns))
1027 | n==n' = ppr n <> pp_export ns
1028 | otherwise = ppr n <> char '|' <> pp_export (n':ns)
1030 pp_export [] = empty
1031 pp_export names = braces (hsep (map ppr names))
1033 pprUsage :: Usage -> SDoc
1035 = hsep [ptext SLIT("import"), ppr (usg_name usage),
1036 int (usg_mod usage),
1037 pp_export_version (usg_exports usage),
1038 int (usg_rules usage),
1039 pp_versions (usg_entities usage) ]
1041 pp_versions nvs = hsep [ ppr n <+> int v | (n,v) <- nvs ]
1042 pp_export_version Nothing = empty
1043 pp_export_version (Just v) = int v
1045 pprDeps :: Dependencies -> SDoc
1046 pprDeps (Deps { dep_mods = mods, dep_pkgs = pkgs, dep_orphs = orphs})
1047 = vcat [ptext SLIT("module dependencies:") <+> fsep (map ppr_mod mods),
1048 ptext SLIT("package dependencies:") <+> fsep (map ppr pkgs),
1049 ptext SLIT("orphans:") <+> fsep (map ppr orphs)
1052 ppr_mod (mod_name, boot) = ppr mod_name <+> ppr_boot boot
1053 ppr_boot True = text "[boot]"
1054 ppr_boot False = empty
1056 pprIfaceDecl :: (Version, IfaceDecl) -> SDoc
1057 pprIfaceDecl (ver, decl)
1058 = ppr_vers ver <+> ppr decl
1060 -- Print the version for the decl
1061 ppr_vers v | v == initialVersion = empty
1064 pprFixities :: [(OccName, Fixity)] -> SDoc
1065 pprFixities [] = empty
1066 pprFixities fixes = ptext SLIT("fixities") <+> pprWithCommas pprFix fixes
1068 pprFix (occ,fix) = ppr fix <+> ppr occ
1070 pprDeprecs NoDeprecs = empty
1071 pprDeprecs (DeprecAll txt) = ptext SLIT("Deprecate all") <+> doubleQuotes (ftext txt)
1072 pprDeprecs (DeprecSome prs) = ptext SLIT("Deprecate") <+> vcat (map pprDeprec prs)
1074 pprDeprec (name, txt) = ppr name <+> doubleQuotes (ftext txt)