DriverPipeline.hs 56.4 KB
Newer Older
1 2 3 4
-----------------------------------------------------------------------------
--
-- GHC Driver
--
5
-- (c) The University of Glasgow 2005
6 7 8
--
-----------------------------------------------------------------------------

9
{-# OPTIONS -w #-}
10 11 12
-- The above warning supression flag is a temporary kludge.
-- While working on this module you are encouraged to remove it and fix
-- any warnings in the module. See
Ian Lynagh's avatar
Ian Lynagh committed
13
--     http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
14 15
-- for details

16
module DriverPipeline (
17 18
	-- Run a series of compilation steps in a pipeline, for a
	-- collection of source files.
19
   oneShot, compileFile,
20

21
	-- Interfaces for the batch-mode driver
22
   linkBinary,
23

24 25 26 27
	-- Interfaces for the compilation manager (interpreted/batch-mode)
   preprocess, 
   compile, CompResult(..), 
   link, 
28

29 30 31 32
  ) where

#include "HsVersions.h"

33
import Packages
34
import HeaderInfo
35
import DriverPhases
36
import SysTools
37
import HscMain
38
import Finder
39 40 41
import HscTypes
import Outputable
import Module
Simon Marlow's avatar
Simon Marlow committed
42
import UniqFM		( eltsUFM )
43
import ErrUtils
44
import DynFlags
45
import StaticFlags	( v_Ld_inputs, opt_Static, opt_HardwireLibPaths, WayName(..) )
46
import Config
47
import Panic
48
import Util
49
import StringBuffer	( hGetStringBuffer )
50
import BasicTypes	( SuccessFlag(..) )
51
import Maybes		( expectJust )
52
import ParserCoreUtils	( getCoreModuleName )
53
import SrcLoc		( unLoc )
54
import SrcLoc		( Located(..) )
55

Simon Marlow's avatar
Simon Marlow committed
56 57 58 59 60 61 62
import Control.Exception as Exception
import Data.IORef	( readIORef, writeIORef, IORef )
import GHC.Exts		( Int(..) )
import System.Directory
import System.IO
import SYSTEM_IO_ERROR as IO
import Control.Monad
63
import Data.List	( isSuffixOf )
Simon Marlow's avatar
Simon Marlow committed
64 65 66
import Data.Maybe
import System.Exit
import System.Environment
67

68 69
-- ---------------------------------------------------------------------------
-- Pre-process
70 71 72

-- Just preprocess a file, put the result in a temp. file (used by the
-- compilation manager during the summary phase).
73 74 75
--
-- We return the augmented DynFlags, because they contain the result
-- of slurping in the OPTIONS pragmas
76

77 78 79
preprocess :: DynFlags -> (FilePath, Maybe Phase) -> IO (DynFlags, FilePath)
preprocess dflags (filename, mb_phase) =
  ASSERT2(isJust mb_phase || isHaskellSrcFilename filename, text filename) 
Simon Marlow's avatar
Simon Marlow committed
80 81
  runPipeline anyHsc dflags (filename, mb_phase) 
        Nothing Temporary Nothing{-no ModLocation-}
82

83 84
-- ---------------------------------------------------------------------------
-- Compile
85 86 87 88 89 90 91 92 93 94

-- Compile a single module, under the control of the compilation manager.
--
-- This is the interface between the compilation manager and the
-- compiler proper (hsc), where we deal with tedious details like
-- reading the OPTIONS pragma from the source file, and passing the
-- output of hsc through the C compiler.

-- NB.  No old interface can also mean that the source has changed.

95
compile :: HscEnv
96
	-> ModSummary
97
	-> Maybe Linkable	-- Just linkable <=> source unchanged
98
        -> Maybe ModIface       -- Old interface, if available
99
        -> Int -> Int
100 101 102
        -> IO CompResult

data CompResult
103 104 105
   = CompOK   ModDetails 	-- New details
              ModIface		-- New iface
              (Maybe Linkable)	-- a Maybe, for the same reasons as hm_linkable
106

107
   | CompErrs 
108 109


110
compile hsc_env mod_summary maybe_old_linkable old_iface mod_index nmods = do 
111

112
   let dflags0     = ms_hspp_opts mod_summary
113 114
       this_mod    = ms_mod mod_summary
       src_flavour = ms_hsc_src mod_summary
115

116 117 118 119
       have_object 
	       | Just l <- maybe_old_linkable, isObjectLinkable l = True
	       | otherwise = False

120 121
   -- FIXME: We need to know whether or not we're recompiling the file. Move this to HscMain?
   --showPass dflags0 ("Compiling " ++ showModMsg have_object mod_summary)
122

123
   let location	  = ms_location mod_summary
124
   let input_fn   = expectJust "compile:hs" (ml_hs_file location) 
125
   let input_fnpp = ms_hspp_file mod_summary
126

127
   debugTraceMsg dflags0 2 (text "compile: input file" <+> text input_fnpp)
128

129
   let (basename, _) = splitFilename input_fn
130

131 132 133 134
  -- We add the directory in which the .hs files resides) to the import path.
  -- This is needed when we try to compile the .hc file later, if it
  -- imports a _stub.h file that we created here.
   let current_dir = directoryOf basename
135 136
       old_paths   = includePaths dflags0
       dflags      = dflags0 { includePaths = current_dir : old_paths }
137

138
   -- Figure out what lang we're generating
139
   let hsc_lang = hscMaybeAdjustTarget dflags StopLn src_flavour (hscTarget dflags)
140
   -- ... and what the next phase should be
141
   let next_phase = hscNextPhase dflags src_flavour hsc_lang
142
   -- ... and what file to generate the output into
143 144
   output_fn <- getOutputFilename next_phase 
			Temporary basename dflags next_phase (Just location)
145

146
   let dflags' = dflags { hscTarget = hsc_lang,
147
				hscOutName = output_fn,
148 149 150
				extCoreName = basename ++ ".hcr" }

   -- -no-recomp should also work with --make
151 152
   let force_recomp = dopt Opt_ForceRecomp dflags
       source_unchanged = isJust maybe_old_linkable && not force_recomp
153
       hsc_env' = hsc_env { hsc_dflags = dflags' }
154
       object_filename = ml_obj_file location
155

156 157 158 159 160
   let getStubLinkable False = return []
       getStubLinkable True
           = do stub_o <- compileStub dflags' this_mod location
                return [ DotO stub_o ]

161
       handleBatch (HscNoRecomp, iface, details)
162 163
           = ASSERT (isJust maybe_old_linkable)
             return (CompOK details iface maybe_old_linkable)
164
       handleBatch (HscRecomp hasStub, iface, details)
165
           | isHsBoot src_flavour
166 167
               = do when (isObjectTarget hsc_lang) $ -- interpreted reaches here too
                       SysTools.touch dflags' "Touching object file"
168 169
                                   object_filename
                    return (CompOK details iface Nothing)
170 171 172 173 174 175 176 177
           | otherwise
               = do stub_unlinked <- getStubLinkable hasStub
                    (hs_unlinked, unlinked_time) <-
                        case hsc_lang of
                          HscNothing
                            -> return ([], ms_hs_date mod_summary)
                          -- We're in --make mode: finish the compilation pipeline.
                          _other
Simon Marlow's avatar
Simon Marlow committed
178 179 180
                            -> do runPipeline StopLn dflags (output_fn,Nothing)
                                              (Just basename)
                                              Persistent
181 182 183 184 185 186 187 188 189 190 191
                                              (Just location)
                                  -- The object filename comes from the ModLocation
                                  o_time <- getModificationTime object_filename
                                  return ([DotO object_filename], o_time)
                    let linkable = LM unlinked_time this_mod
			           (hs_unlinked ++ stub_unlinked)
                    return (CompOK details iface (Just linkable))

       handleInterpreted (InteractiveNoRecomp, iface, details)
           = ASSERT (isJust maybe_old_linkable)
             return (CompOK details iface maybe_old_linkable)
192
       handleInterpreted (InteractiveRecomp hasStub comp_bc modBreaks, iface, details)
193
           = do stub_unlinked <- getStubLinkable hasStub
194
                let hs_unlinked = [BCOs comp_bc modBreaks]
195 196 197 198 199 200 201 202 203 204 205 206 207
                    unlinked_time = ms_hs_date mod_summary
                  -- Why do we use the timestamp of the source file here,
                  -- rather than the current time?  This works better in
                  -- the case where the local clock is out of sync
                  -- with the filesystem's clock.  It's just as accurate:
                  -- if the source is modified, then the linkable will
                  -- be out of date.
                let linkable = LM unlinked_time this_mod
                               (hs_unlinked ++ stub_unlinked)
                return (CompOK details iface (Just linkable))

   let runCompiler compiler handle
           = do mbResult <- compiler hsc_env' mod_summary
208
                                     source_unchanged old_iface
209 210 211 212
                                     (Just (mod_index, nmods))
                case mbResult of
                  Nothing     -> return CompErrs
                  Just result -> handle result
213
   -- run the compiler
214
   case hsc_lang of
215 216 217 218 219
     HscInterpreted
      | isHsBoot src_flavour -> runCompiler hscCompileNothing handleBatch
      | otherwise            -> runCompiler hscCompileInteractive handleInterpreted
     HscNothing     -> runCompiler hscCompileNothing handleBatch
     _other         -> runCompiler hscCompileBatch handleBatch
220

221
-----------------------------------------------------------------------------
222 223
-- stub .h and .c files (for foreign export support)

224 225 226
-- The _stub.c file is derived from the haskell source file, possibly taking
-- into account the -stubdir option.
--
227 228 229 230 231 232 233 234 235 236 237 238 239
-- Consequently, we derive the _stub.o filename from the haskell object
-- filename.  
--
-- This isn't necessarily the same as the object filename we
-- would get if we just compiled the _stub.c file using the pipeline.
-- For example:
--
--    ghc src/A.hs -odir obj
-- 
-- results in obj/A.o, and src/A_stub.c.  If we compile src/A_stub.c with
-- -odir obj, we would get obj/src/A_stub.o, which is wrong; we want
-- obj/A_stub.o.

240 241 242
compileStub :: DynFlags -> Module -> ModLocation -> IO FilePath
compileStub dflags mod location = do
	let (o_base, o_ext) = splitFilename (ml_obj_file location)
243 244
	    stub_o = o_base ++ "_stub" `joinFileExt` o_ext

245
	-- compile the _stub.c file w/ gcc
Simon Marlow's avatar
Simon Marlow committed
246
	let (stub_c,_) = mkStubPaths dflags (moduleName mod) location
Simon Marlow's avatar
Simon Marlow committed
247
	runPipeline StopLn dflags (stub_c,Nothing)  Nothing
248 249 250
		(SpecificFile stub_o) Nothing{-no ModLocation-}

	return stub_o
251 252


253 254
-- ---------------------------------------------------------------------------
-- Link
255

256
link :: GhcLink			-- interactive or batch
257 258
     -> DynFlags		-- dynamic flags
     -> Bool			-- attempt linking in batch mode?
259
     -> HomePackageTable	-- what to link
260 261 262 263 264 265 266 267 268 269
     -> IO SuccessFlag

-- For the moment, in the batch linker, we don't bother to tell doLink
-- which packages to link -- it just tries all that are available.
-- batch_attempt_linking should only be *looked at* in batch mode.  It
-- should only be True if the upsweep was successful and someone
-- exports main, i.e., we have good reason to believe that linking
-- will succeed.

#ifdef GHCI
270
link LinkInMemory dflags batch_attempt_linking hpt
271
    = do -- Not Linking...(demand linker will do the job)
272 273 274
	 return Succeeded
#endif

275
link NoLink dflags batch_attempt_linking hpt
276 277
   = return Succeeded

278
link LinkBinary dflags batch_attempt_linking hpt
279
   | batch_attempt_linking
280
   = do 
281
	let 
Simon Marlow's avatar
Simon Marlow committed
282
	    home_mod_infos = eltsUFM hpt
283 284 285 286 287

	    -- the packages we depend on
	    pkg_deps  = concatMap (dep_pkgs . mi_deps . hm_iface) home_mod_infos

	    -- the linkables to link
288
	    linkables = map (expectJust "link".hm_linkable) home_mod_infos
289

290
        debugTraceMsg dflags 3 (text "link: linkables are ..." $$ vcat (map ppr linkables))
291

292
	-- check for the -no-link flag
293
	if isNoLink (ghcLink dflags)
294
	  then do debugTraceMsg dflags 3 (text "link(batch): linking omitted (-c flag given).")
295 296 297
	          return Succeeded
	  else do

298 299 300
	let getOfiles (LM _ _ us) = map nameOfObject (filter isObject us)
	    obj_files = concatMap getOfiles linkables

301 302 303 304 305 306 307 308 309 310 311
	    exe_file = exeFileName dflags

	-- if the modification time on the executable is later than the
	-- modification times on all of the objects, then omit linking
	-- (unless the -no-recomp flag was given).
	e_exe_time <- IO.try $ getModificationTime exe_file
	let linking_needed 
		| Left _  <- e_exe_time = True
		| Right t <- e_exe_time = 
			any (t <) (map linkableTime linkables)

312
	if not (dopt Opt_ForceRecomp dflags) && not linking_needed
313
	   then do debugTraceMsg dflags 2 (text exe_file <+> ptext SLIT("is up to date, linking not required."))
314 315 316
		   return Succeeded
	   else do

317 318
	debugTraceMsg dflags 1 (ptext SLIT("Linking") <+> text exe_file
				 <+> text "...")
319

320
	-- Don't showPass in Batch mode; doLink will do that for us.
321
	let link = case ghcLink dflags of
322 323
	        LinkBinary  -> linkBinary
	        LinkDynLib  -> linkDynLib
324
	link dflags obj_files pkg_deps
325

326
        debugTraceMsg dflags 3 (text "link: done")
327

328
	-- linkBinary only returns if it succeeds
329 330 331
        return Succeeded

   | otherwise
332 333
   = do debugTraceMsg dflags 3 (text "link(batch): upsweep (partially) failed OR" $$
                                text "   Main.main not exported; not linking.")
334
        return Succeeded
335
      
336 337 338
-- -----------------------------------------------------------------------------
-- Compile files in one-shot mode.

339
oneShot :: DynFlags -> Phase -> [(String, Maybe Phase)] -> IO ()
340 341 342 343
oneShot dflags stop_phase srcs = do
  o_files <- mapM (compileFile dflags stop_phase) srcs
  doLink dflags stop_phase o_files

344 345
compileFile :: DynFlags -> Phase -> (FilePath, Maybe Phase) -> IO FilePath
compileFile dflags stop_phase (src, mb_phase) = do
346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368
   exists <- doesFileExist src
   when (not exists) $ 
   	throwDyn (CmdLineError ("does not exist: " ++ src))
   
   let
	split     = dopt Opt_SplitObjs dflags
	mb_o_file = outputFile dflags
	ghc_link  = ghcLink dflags	-- Set by -c or -no-link

	-- When linking, the -o argument refers to the linker's output.	
	-- otherwise, we use it as the name for the pipeline's output.
        output
	 | StopLn <- stop_phase, not (isNoLink ghc_link) = Persistent
		-- -o foo applies to linker
	 | Just o_file <- mb_o_file = SpecificFile o_file
		-- -o foo applies to the file we are compiling now
	 | otherwise = Persistent

        stop_phase' = case stop_phase of 
			As | split -> SplitAs
			other      -> stop_phase

   (_, out_file) <- runPipeline stop_phase' dflags
Simon Marlow's avatar
Simon Marlow committed
369 370
			  (src, mb_phase) Nothing output 
                          Nothing{-no ModLocation-}
371 372 373 374 375 376 377 378 379 380 381
   return out_file


doLink :: DynFlags -> Phase -> [FilePath] -> IO ()
doLink dflags stop_phase o_files
  | not (isStopLn stop_phase)
  = return ()		-- We stopped before the linking phase

  | otherwise
  = case ghcLink dflags of
	NoLink     -> return ()
382 383
	LinkBinary -> linkBinary dflags o_files link_pkgs
	LinkDynLib -> linkDynLib dflags o_files []
384 385 386
  where
   -- Always link in the haskell98 package for static linking.  Other
   -- packages have to be specified via the -package flag.
Simon Marlow's avatar
Simon Marlow committed
387
    link_pkgs = [haskell98PackageId]
388 389


390 391
-- ---------------------------------------------------------------------------
-- Run a compilation pipeline, consisting of multiple phases.
392

393 394 395 396
-- This is the interface to the compilation pipeline, which runs
-- a series of compilation steps on a single source file, specifying
-- at which stage to stop.

397
-- The DynFlags can be modified by phases in the pipeline (eg. by
398 399 400 401 402 403 404 405 406 407 408 409 410
-- GHC_OPTIONS pragmas), and the changes affect later phases in the
-- pipeline.

data PipelineOutput 
  = Temporary
	-- output should be to a temporary file: we're going to
	-- run more compilation steps on this output later
  | Persistent
	-- we want a persistent file, i.e. a file in the current directory
	-- derived from the input filename, but with the appropriate extension.
	-- eg. in "ghc -c Foo.hs" the output goes into ./Foo.o.
  | SpecificFile FilePath
	-- the output must go into the specified file.
411

412
runPipeline
413 414 415
  :: Phase		        -- When to stop
  -> DynFlags		        -- Dynamic flags
  -> (FilePath,Maybe Phase)     -- Input filename (and maybe -x suffix)
Simon Marlow's avatar
Simon Marlow committed
416
  -> Maybe FilePath             -- original basename (if different from ^^^)
417 418
  -> PipelineOutput	        -- Output filename
  -> Maybe ModLocation          -- A ModLocation, if this is a Haskell module
419
  -> IO (DynFlags, FilePath)	-- (final flags, output filename)
420

421
runPipeline stop_phase dflags0 (input_fn, mb_phase) mb_basename output maybe_loc
422
  = do
423 424
  let
      (input_basename, suffix) = splitFilename input_fn
Simon Marlow's avatar
Simon Marlow committed
425 426
      basename | Just b <- mb_basename = b
               | otherwise             = input_basename
427

428 429 430
      -- Decide where dump files should go based on the pipeline output
      dflags = dflags0 { dumpPrefix = Just (basename ++ ".") }

431
	-- If we were given a -x flag, then use that phase to start from
basvandijk@home.nl's avatar
basvandijk@home.nl committed
432
      start_phase = fromMaybe (startPhase suffix) mb_phase
433

434 435 436 437 438 439
  -- We want to catch cases of "you can't get there from here" before
  -- we start the pipeline, because otherwise it will just run off the
  -- end.
  --
  -- There is a partial ordering on phases, where A < B iff A occurs
  -- before B in a normal compilation pipeline.
440

441 442
  when (not (start_phase `happensBefore` stop_phase)) $
	throwDyn (UsageError 
443 444
		    ("cannot compile this file to desired target: "
		       ++ input_fn))
445

446 447
  -- this is a function which will be used to calculate output file names
  -- as we go along (we partially apply it to some of its inputs here)
448
  let get_output_fn = getOutputFilename stop_phase output basename
449

450
  -- Execute the pipeline...
451 452 453
  (dflags', output_fn, maybe_loc) <- 
	pipeLoop dflags start_phase stop_phase input_fn 
	  	 basename suffix get_output_fn maybe_loc
454

455
  -- Sometimes, a compilation phase doesn't actually generate any output
456 457
  -- (eg. the CPP phase when -fcpp is not turned on).  If we end on this
  -- stage, but we wanted to keep the output, then we have to explicitly
458 459
  -- copy the file, remembering to prepend a {-# LINE #-} pragma so that
  -- further compilation stages can tell what the original filename was.
460 461 462 463
  case output of
    Temporary -> 
	return (dflags', output_fn)
    _other ->
464
	do final_fn <- get_output_fn dflags' stop_phase maybe_loc
465 466 467 468
	   when (final_fn /= output_fn) $ do
              let msg = ("Copying `" ++ output_fn ++"' to `" ++ final_fn ++ "'")
                  line_prag = Just ("{-# LINE 1 \"" ++ input_fn ++ "\" #-}\n")
	      copyWithHeader dflags msg line_prag output_fn final_fn
469
	   return (dflags', final_fn)
470

471 472


473
pipeLoop :: DynFlags -> Phase -> Phase 
474
	 -> FilePath  -> String -> Suffix
475
	 -> (DynFlags -> Phase -> Maybe ModLocation -> IO FilePath)
476 477
	 -> Maybe ModLocation
	 -> IO (DynFlags, FilePath, Maybe ModLocation)
478

479
pipeLoop dflags phase stop_phase 
480 481
	 input_fn orig_basename orig_suff 
	 orig_get_output_fn maybe_loc
482

483 484
  | phase `eqPhase` stop_phase		  -- All done
  = return (dflags, input_fn, maybe_loc)
485

486
  | not (phase `happensBefore` stop_phase)
487 488 489 490
	-- Something has gone wrong.  We'll try to cover all the cases when
	-- this could happen, so if we reach here it is a panic.
	-- eg. it might happen if the -C flag is used on a source file that
	-- has {-# OPTIONS -fasm #-}.
491 492 493 494 495
  = panic ("pipeLoop: at phase " ++ show phase ++ 
	   " but I wanted to stop at phase " ++ show stop_phase)

  | otherwise 
  = do	{ (next_phase, dflags', maybe_loc, output_fn)
496
		<- runPhase phase stop_phase dflags orig_basename 
497
			    orig_suff input_fn orig_get_output_fn maybe_loc
498
	; pipeLoop dflags' next_phase stop_phase output_fn
499 500
		   orig_basename orig_suff orig_get_output_fn maybe_loc }

501
getOutputFilename
502 503 504
  :: Phase -> PipelineOutput -> String
  -> DynFlags -> Phase{-next phase-} -> Maybe ModLocation -> IO FilePath
getOutputFilename stop_phase output basename
505 506
 = func
 where
507
	func dflags next_phase maybe_location
508 509 510 511
	   | is_last_phase, Persistent <- output     = persistent_fn
	   | is_last_phase, SpecificFile f <- output = return f
	   | keep_this_output	   		     = persistent_fn
     	   | otherwise        	   		     = newTempName dflags suffix
512
	   where
513 514 515 516 517 518 519 520 521 522 523
		hcsuf      = hcSuf dflags
		odir       = objectDir dflags
		osuf       = objectSuf dflags
		keep_hc    = dopt Opt_KeepHcFiles dflags
		keep_raw_s = dopt Opt_KeepRawSFiles dflags
		keep_s     = dopt Opt_KeepSFiles dflags

		myPhaseInputExt HCc    = hcsuf
		myPhaseInputExt StopLn = osuf
		myPhaseInputExt other  = phaseInputExt other

524
		is_last_phase = next_phase `eqPhase` stop_phase
525 526 527 528

		-- sometimes, we keep output from intermediate stages
		keep_this_output = 
     		     case next_phase of
529
     			     StopLn              -> True
530 531 532 533 534
     			     Mangle | keep_raw_s -> True
     			     As     | keep_s     -> True
     			     HCc    | keep_hc    -> True
     			     _other              -> False

535
		suffix = myPhaseInputExt next_phase
536 537 538

		-- persistent object files get put in odir
	        persistent_fn 
539 540
		   | StopLn <- next_phase = return odir_persistent
		   | otherwise            = return persistent
541

542
		persistent = basename `joinFileExt` suffix
543

544
		odir_persistent
545
		   | Just loc <- maybe_location = ml_obj_file loc
546
		   | Just d <- odir = d `joinFileName` persistent
547 548
		   | otherwise      = persistent

549

550 551 552 553 554 555 556 557 558 559
-- -----------------------------------------------------------------------------
-- Each phase in the pipeline returns the next phase to execute, and the
-- name of the file in which the output was placed.
--
-- We must do things dynamically this way, because we often don't know
-- what the rest of the phases will be until part-way through the
-- compilation: for example, an {-# OPTIONS -fasm #-} at the beginning
-- of a source file can change the latter stages of the pipeline from
-- taking the via-C route to using the native code generator.

560 561
runPhase :: Phase	-- Do this phase first
	 -> Phase	-- Stop just before this phase
562 563 564 565
	 -> DynFlags
	 -> String	-- basename of original input source
	 -> String	-- its extension
	 -> FilePath	-- name of file which contains the input to this phase.
566
	 -> (DynFlags -> Phase -> Maybe ModLocation -> IO FilePath)
567
			-- how to calculate the output filename
568
	 -> Maybe ModLocation		-- the ModLocation, if we have one
569
	 -> IO (Phase,	  		-- next phase
570 571 572
		DynFlags,		-- new dynamic flags
		Maybe ModLocation,	-- the ModLocation, if we have one
		FilePath)		-- output filename
573

574 575 576 577
	-- Invariant: the output filename always contains the output
	-- Interesting case: Hsc when there is no recompilation to do
	--		     Then the output filename is still a .o file 

578 579 580
-------------------------------------------------------------------------------
-- Unlit phase 

581
runPhase (Unlit sf) _stop dflags _basename _suff input_fn get_output_fn maybe_loc
582
  = do let unlit_flags = getOpts dflags opt_L
rrt's avatar
rrt committed
583
       -- The -h option passes the file name for unlit to put in a #line directive
584
       output_fn <- get_output_fn dflags (Cpp sf) maybe_loc
585

586 587
       SysTools.runUnlit dflags 
		(map SysTools.Option unlit_flags ++
sof's avatar
sof committed
588 589
       			  [ SysTools.Option     "-h"
 			  , SysTools.Option     input_fn
sof's avatar
sof committed
590 591
			  , SysTools.FileOption "" input_fn
			  , SysTools.FileOption "" output_fn
sof's avatar
sof committed
592
			  ])
593

594
       return (Cpp sf, dflags, maybe_loc, output_fn)
595 596

-------------------------------------------------------------------------------
597 598
-- Cpp phase : (a) gets OPTIONS out of file
--	       (b) runs cpp if necessary
599

600
runPhase (Cpp sf) _stop dflags0 basename suff input_fn get_output_fn maybe_loc
601 602
  = do src_opts <- getOptionsFromFile input_fn
       (dflags,unhandled_flags) <- parseDynamicFlags dflags0 (map unLoc src_opts)
603
       checkProcessArgsResult unhandled_flags (basename `joinFileExt` suff)
604

605
       if not (dopt Opt_Cpp dflags) then
sof's avatar
sof committed
606 607
           -- no need to preprocess CPP, just pass input file along
	   -- to the next phase of the pipeline.
608
          return (HsPp sf, dflags, maybe_loc, input_fn)
sof's avatar
sof committed
609
	else do
610
	    output_fn <- get_output_fn dflags (HsPp sf) maybe_loc
611
	    doCpp dflags True{-raw-} False{-no CC opts-} input_fn output_fn
612
	    return (HsPp sf, dflags, maybe_loc, output_fn)
613

sof's avatar
sof committed
614 615 616
-------------------------------------------------------------------------------
-- HsPp phase 

617
runPhase (HsPp sf) _stop dflags basename suff input_fn get_output_fn maybe_loc
618
  = do if not (dopt Opt_Pp dflags) then
sof's avatar
sof committed
619 620
           -- no need to preprocess, just pass input file along
	   -- to the next phase of the pipeline.
621
          return (Hsc sf, dflags, maybe_loc, input_fn)
sof's avatar
sof committed
622
	else do
623
	    let hspp_opts = getOpts dflags opt_F
624
	    let orig_fn = basename `joinFileExt` suff
625
	    output_fn <- get_output_fn dflags (Hsc sf) maybe_loc
626 627
	    SysTools.runPp dflags
			   ( [ SysTools.Option     orig_fn
sof's avatar
sof committed
628 629 630 631 632
			     , SysTools.Option     input_fn
			     , SysTools.FileOption "" output_fn
			     ] ++
			     map SysTools.Option hspp_opts
			   )
633
	    return (Hsc sf, dflags, maybe_loc, output_fn)
634

635 636 637
-----------------------------------------------------------------------------
-- Hsc phase

638 639
-- Compilation of a single module, in "legacy" mode (_not_ under
-- the direction of the compilation manager).
640
runPhase (Hsc src_flavour) stop dflags0 basename suff input_fn get_output_fn _maybe_loc 
641
 = do	-- normal Hsc mode, not mkdependHS
642

643 644 645
  -- we add the current directory (i.e. the directory in which
  -- the .hs files resides) to the import path, since this is
  -- what gcc does, and it's probably what you want.
646
	let current_dir = directoryOf basename
647
	
648 649
	    paths = includePaths dflags0
	    dflags = dflags0 { includePaths = current_dir : paths }
650
	
651
  -- gather the imports and module name
652
        (hspp_buf,mod_name,imps,src_imps) <- 
653 654 655
            case src_flavour of
		ExtCoreFile -> do {  -- no explicit imports in ExtCore input.
			          ; m <- getCoreModuleName input_fn
656
			          ; return (Nothing, mkModuleName m, [], []) }
657 658

		other -> do { buf <- hGetStringBuffer input_fn
659
			    ; (src_imps,imps,L _ mod_name) <- getImports dflags buf input_fn (basename `joinFileExt` suff)
660
			    ; return (Just buf, mod_name, imps, src_imps) }
661 662 663 664 665 666 667

  -- Build a ModLocation to pass to hscMain.
  -- The source filename is rather irrelevant by now, but it's used
  -- by hscMain for messages.  hscMain also needs 
  -- the .hi and .o filenames, and this is as good a way
  -- as any to generate them, and better than most. (e.g. takes 
  -- into accout the -osuf flags)
668
	location1 <- mkHomeModLocation2 dflags mod_name basename suff
669 670 671 672 673 674 675 676 677

  -- Boot-ify it if necessary
	let location2 | isHsBoot src_flavour = addBootSuffixLocn location1
		      | otherwise	     = location1 
					

  -- Take -ohi into account if present
  -- This can't be done in mkHomeModuleLocation because
  -- it only applies to the module being compiles
678 679
	let ohi = outputHi dflags
	    location3 | Just fn <- ohi = location2{ ml_hi_file = fn }
680 681 682 683 684 685 686
		      | otherwise      = location2

  -- Take -o into account if present
  -- Very like -ohi, but we must *only* do this if we aren't linking
  -- (If we're linking then the -o applies to the linked thing, not to
  -- the object file for one module.)
  -- Note the nasty duplication with the same computation in compileFile above
687 688 689
	let expl_o_file = outputFile dflags
	    location4 | Just ofile <- expl_o_file
		      , isNoLink (ghcLink dflags)
690 691 692 693 694 695 696
		      = location3 { ml_obj_file = ofile }
		      | otherwise = location3

	    o_file = ml_obj_file location4 	-- The real object file


  -- Figure out if the source has changed, for recompilation avoidance.
697
  --
698
  -- Setting source_unchanged to True means that M.o seems
699 700
  -- to be up to date wrt M.hs; so no need to recompile unless imports have
  -- changed (which the compiler itself figures out).
701
  -- Setting source_unchanged to False tells the compiler that M.o is out of
702
  -- date wrt M.hs (or M.o doesn't exist) so we must recompile regardless.
Simon Marlow's avatar
Simon Marlow committed
703 704
	src_timestamp <- getModificationTime (basename `joinFileExt` suff)

705
	let force_recomp = dopt Opt_ForceRecomp dflags
706
	source_unchanged <- 
707
          if force_recomp || not (isStopLn stop)
708 709
		-- Set source_unchanged to False unconditionally if
		--	(a) recompilation checker is off, or
710
		-- 	(b) we aren't going all the way to .o file (e.g. ghc -S)
711 712
	     then return False	
		-- Otherwise look at file modification dates
713
	     else do o_file_exists <- doesFileExist o_file
714
		     if not o_file_exists
715
		        then return False	-- Need to recompile
716
			else do t2 <- getModificationTime o_file
717
			        if t2 > src_timestamp
718 719
				  then return True
				  else return False
720

721
  -- get the DynFlags
722
	let hsc_lang = hscMaybeAdjustTarget dflags stop src_flavour (hscTarget dflags)
723
	let next_phase = hscNextPhase dflags src_flavour hsc_lang
724
	output_fn  <- get_output_fn dflags next_phase (Just location4)
725

726
        let dflags' = dflags { hscTarget = hsc_lang,
727 728
			       hscOutName = output_fn,
			       extCoreName = basename ++ ".hcr" }
729

730
	hsc_env <- newHscEnv dflags'
731

732
  -- Tell the finder cache about this module
Simon Marlow's avatar
Simon Marlow committed
733 734 735 736 737 738 739 740 741 742 743 744 745 746
	mod <- addHomeModuleToFinder hsc_env mod_name location4

  -- Make the ModSummary to hand to hscMain
	let
	    unused_field = panic "runPhase:ModSummary field"
		-- Some fields are not looked at by hscMain
	    mod_summary = ModSummary {	ms_mod 	     = mod, 
					ms_hsc_src   = src_flavour,
				 	ms_hspp_file = input_fn,
                                        ms_hspp_opts = dflags,
					ms_hspp_buf  = hspp_buf,
					ms_location  = location4,
					ms_hs_date   = src_timestamp,
					ms_obj_date  = Nothing,
747 748
					ms_imps	     = imps,
					ms_srcimps   = src_imps }
749

750
  -- run the compiler!
751
	mbResult <- hscCompileOneShot hsc_env
752 753
			  mod_summary source_unchanged 
			  Nothing	-- No iface
754
                          Nothing       -- No "module i of n" progress info
755

756 757
	case mbResult of
          Nothing -> throwDyn (PhaseFailed "hsc" (ExitFailure 1))
758
          Just HscNoRecomp
759 760 761 762 763
              -> do SysTools.touch dflags' "Touching object file" o_file
                    -- The .o file must have a later modification date
                    -- than the source file (else we wouldn't be in HscNoRecomp)
                    -- but we touch it anyway, to keep 'make' happy (we think).
                    return (StopLn, dflags', Just location4, o_file)
764
          Just (HscRecomp hasStub)
765
              -> do when hasStub $
Simon Marlow's avatar
Simon Marlow committed
766
                         do stub_o <- compileStub dflags' mod location4
767 768 769 770 771 772
                            consIORef v_Ld_inputs stub_o
                    -- In the case of hs-boot files, generate a dummy .o-boot 
                    -- stamp file for the benefit of Make
                    when (isHsBoot src_flavour) $
                      SysTools.touch dflags' "Touching object file" o_file
                    return (next_phase, dflags', Just location4, output_fn)
773

774 775 776
-----------------------------------------------------------------------------
-- Cmm phase

777
runPhase CmmCpp stop dflags basename suff input_fn get_output_fn maybe_loc
778
  = do
779
       output_fn <- get_output_fn dflags Cmm maybe_loc
780
       doCpp dflags False{-not raw-} True{-include CC opts-} input_fn output_fn	
781
       return (Cmm, dflags, maybe_loc, output_fn)
782

783
runPhase Cmm stop dflags basename suff input_fn get_output_fn maybe_loc
784
  = do
785
	let hsc_lang = hscMaybeAdjustTarget dflags stop HsSrcFile (hscTarget dflags)
786
	let next_phase = hscNextPhase dflags HsSrcFile hsc_lang
787
	output_fn <- get_output_fn dflags next_phase maybe_loc
788

789
        let dflags' = dflags { hscTarget = hsc_lang,
790 791
			       hscOutName = output_fn,
			       extCoreName = basename ++ ".hcr" }
792

793
	ok <- hscCmmFile dflags' input_fn
794 795 796

	when (not ok) $ throwDyn (PhaseFailed "cmm" (ExitFailure 1))

797
	return (next_phase, dflags, maybe_loc, output_fn)
798

799 800 801 802 803 804
-----------------------------------------------------------------------------
-- Cc phase

-- we don't support preprocessing .c files (with -E) now.  Doing so introduces
-- way too many hacks, and I can't say I've ever used it anyway.

805
runPhase cc_phase stop dflags basename suff input_fn get_output_fn maybe_loc
806
   | cc_phase `eqPhase` Cc || cc_phase `eqPhase` Ccpp || cc_phase `eqPhase` HCc
807
   = do	let cc_opts = getOpts dflags opt_c
808
	    hcc = cc_phase `eqPhase` HCc
809

810
       	let cmdline_include_paths = includePaths dflags
811

812 813 814 815 816 817
	-- HC files have the dependent packages stamped into them
	pkgs <- if hcc then getHCFilePackages input_fn else return []

	-- add package include paths even if we're just compiling .c
	-- files; this is the Value Add(TM) that using ghc instead of
	-- gcc gives you :)
818
        pkg_include_dirs <- getPackageIncludePath dflags pkgs
rrt's avatar
rrt committed
819 820
        let include_paths = foldr (\ x xs -> "-I" : x : xs) []
			      (cmdline_include_paths ++ pkg_include_dirs)
821

822
	let (md_c_flags, md_regd_c_flags) = machdepCCOpts dflags
823
        gcc_extra_viac_flags <- getExtraViaCOpts dflags
824
        let pic_c_flags = picCCOpts dflags
825

826
        let verb = getVerbFlag dflags
827

828
	pkg_extra_cc_opts <- getPackageExtraCcOpts dflags pkgs
829

830 831
	let split_objs = dopt Opt_SplitObjs dflags
	    split_opt | hcc && split_objs = [ "-DUSE_SPLIT_MARKERS" ]
sof's avatar
sof committed
832
		      | otherwise         = [ ]
833

834
	let excessPrecision = dopt Opt_ExcessPrecision dflags
835

Simon Marlow's avatar
Simon Marlow committed
836 837 838
	let cc_opt | optLevel dflags >= 2 = "-O2"
		   | otherwise            = "-O"

839
	-- Decide next phase
840 841 842
	
        let mangle = dopt Opt_DoAsmMangling dflags
            next_phase
843 844
		| hcc && mangle     = Mangle
		| otherwise         = As
845
	output_fn <- get_output_fn dflags next_phase maybe_loc
846

847 848
	let
	  more_hcc_opts =
849
#if i386_TARGET_ARCH
850 851 852 853 854 855 856 857 858 859 860 861 862 863
	   	-- on x86 the floating point regs have greater precision
	     	-- than a double, which leads to unpredictable results.
		-- By default, we turn this off with -ffloat-store unless
		-- the user specified -fexcess-precision.
		(if excessPrecision then [] else [ "-ffloat-store" ]) ++
#endif
		-- gcc's -fstrict-aliasing allows two accesses to memory
		-- to be considered non-aliasing if they have different types.
		-- This interacts badly with the C code we generate, which is
		-- very weakly typed, being derived from C--.
		["-fno-strict-aliasing"]



864 865 866 867 868
	SysTools.runCc dflags (
		-- force the C compiler to interpret this file as C when
		-- compiling .hc files, by adding the -x c option.
		-- Also useful for plain .c files, just in case GHC saw a 
		-- -x c option.
869 870
			[ SysTools.Option "-x", if cc_phase `eqPhase` Ccpp
                                                then SysTools.Option "c++" else SysTools.Option "c"] ++
871
			[ SysTools.FileOption "" input_fn
sof's avatar
sof committed
872
			, SysTools.Option "-o"
sof's avatar
sof committed
873
			, SysTools.FileOption "" output_fn
sof's avatar
sof committed
874 875 876
			]
		       ++ map SysTools.Option (
		          md_c_flags
877
                       ++ pic_c_flags