2 % (c) The AQUA Project, Glasgow University, 1994-1998
4 \section[ErrsUtils]{Utilities for error reporting}
8 Message, mkLocMessage, printError,
12 ErrorMessages, WarningMessages,
13 Messages, errorsFound, emptyMessages,
14 mkErrMsg, mkPlainErrMsg, mkLongErrMsg, mkWarnMsg, mkPlainWarnMsg,
15 printErrorsAndWarnings, printBagOfErrors, printBagOfWarnings,
20 dumpIfSet, dumpIf_core, dumpIfSet_core, dumpIfSet_dyn, dumpIfSet_dyn_or,
23 -- * Messages during compilation
27 compilationProgressMsg,
32 #include "HsVersions.h"
34 import Bag ( Bag, bagToList, isEmptyBag, emptyBag )
35 import Util ( sortLe )
38 import DynFlags ( DynFlags(..), DynFlag(..), dopt )
39 import StaticFlags ( opt_ErrorSpans )
42 import System.Exit ( ExitCode(..), exitWith )
46 -- -----------------------------------------------------------------------------
47 -- Basic error messages: just render a message with a source location.
57 mkLocMessage :: SrcSpan -> Message -> Message
59 | opt_ErrorSpans = hang (ppr locn <> colon) 4 msg
60 | otherwise = hang (ppr (srcSpanStart locn) <> colon) 4 msg
61 -- always print the location, even if it is unhelpful. Error messages
62 -- are supposed to be in a standard format, and one without a location
63 -- would look strange. Better to say explicitly "<no location info>".
65 printError :: SrcSpan -> Message -> IO ()
66 printError span msg = printErrs (mkLocMessage span msg $ defaultErrStyle)
69 -- -----------------------------------------------------------------------------
70 -- Collecting up messages for later ordering and printing.
72 data ErrMsg = ErrMsg {
73 errMsgSpans :: [SrcSpan],
74 errMsgContext :: PrintUnqualified,
75 errMsgShortDoc :: Message,
76 errMsgExtraInfo :: Message
78 -- The SrcSpan is used for sorting errors into line-number order
80 instance Show ErrMsg where
81 show em = showSDoc (errMsgShortDoc em)
85 -- A short (one-line) error message, with context to tell us whether
86 -- to qualify names in the message or not.
87 mkErrMsg :: SrcSpan -> PrintUnqualified -> Message -> ErrMsg
88 mkErrMsg locn print_unqual msg
89 = ErrMsg { errMsgSpans = [locn], errMsgContext = print_unqual
90 , errMsgShortDoc = msg, errMsgExtraInfo = empty }
92 -- Variant that doesn't care about qualified/unqualified names
93 mkPlainErrMsg :: SrcSpan -> Message -> ErrMsg
94 mkPlainErrMsg locn msg
95 = ErrMsg { errMsgSpans = [locn], errMsgContext = alwaysQualify
96 , errMsgShortDoc = msg, errMsgExtraInfo = empty }
98 -- A long (multi-line) error message, with context to tell us whether
99 -- to qualify names in the message or not.
100 mkLongErrMsg :: SrcSpan -> PrintUnqualified -> Message -> Message -> ErrMsg
101 mkLongErrMsg locn print_unqual msg extra
102 = ErrMsg { errMsgSpans = [locn], errMsgContext = print_unqual
103 , errMsgShortDoc = msg, errMsgExtraInfo = extra }
105 mkWarnMsg :: SrcSpan -> PrintUnqualified -> Message -> WarnMsg
108 -- Variant that doesn't care about qualified/unqualified names
109 mkPlainWarnMsg :: SrcSpan -> Message -> ErrMsg
110 mkPlainWarnMsg locn msg = mkWarnMsg locn alwaysQualify msg
112 type Messages = (Bag WarnMsg, Bag ErrMsg)
114 type WarningMessages = Bag WarnMsg
115 type ErrorMessages = Bag ErrMsg
117 emptyMessages :: Messages
118 emptyMessages = (emptyBag, emptyBag)
120 warnIsErrorMsg :: ErrMsg
121 warnIsErrorMsg = mkPlainErrMsg noSrcSpan (text "\nFailing due to -Werror.\n")
123 errorsFound :: DynFlags -> Messages -> Bool
124 -- The dyn-flags are used to see if the user has specified
125 -- -Werror, which says that warnings should be fatal
126 errorsFound dflags (warns, errs)
127 | dopt Opt_WarnIsError dflags = not (isEmptyBag errs) || not (isEmptyBag warns)
128 | otherwise = not (isEmptyBag errs)
130 printErrorsAndWarnings :: DynFlags -> Messages -> IO ()
131 printErrorsAndWarnings dflags (warns, errs)
132 | no_errs && no_warns = return ()
133 | no_errs = do printBagOfWarnings dflags warns
134 when (dopt Opt_WarnIsError dflags) $
136 text "\nFailing due to -Werror.\n"
137 -- Don't print any warnings if there are errors
138 | otherwise = printBagOfErrors dflags errs
140 no_warns = isEmptyBag warns
141 no_errs = isEmptyBag errs
143 printBagOfErrors :: DynFlags -> Bag ErrMsg -> IO ()
144 printBagOfErrors dflags bag_of_errors
145 = sequence_ [ let style = mkErrStyle unqual
146 in log_action dflags SevError s style (d $$ e)
147 | ErrMsg { errMsgSpans = s:_,
150 errMsgContext = unqual } <- sorted_errs ]
152 bag_ls = bagToList bag_of_errors
153 sorted_errs = sortLe occ'ed_before bag_ls
155 occ'ed_before err1 err2 =
156 case compare (head (errMsgSpans err1)) (head (errMsgSpans err2)) of
161 printBagOfWarnings :: DynFlags -> Bag ErrMsg -> IO ()
162 printBagOfWarnings dflags bag_of_warns
163 = sequence_ [ let style = mkErrStyle unqual
164 in log_action dflags SevWarning s style (d $$ e)
165 | ErrMsg { errMsgSpans = s:_,
168 errMsgContext = unqual } <- sorted_errs ]
170 bag_ls = bagToList bag_of_warns
171 sorted_errs = sortLe occ'ed_before bag_ls
173 occ'ed_before err1 err2 =
174 case compare (head (errMsgSpans err1)) (head (errMsgSpans err2)) of
179 ghcExit :: DynFlags -> Int -> IO ()
181 | val == 0 = exitWith ExitSuccess
182 | otherwise = do errorMsg dflags (text "\nCompilation had errors\n\n")
183 exitWith (ExitFailure val)
185 doIfSet :: Bool -> IO () -> IO ()
186 doIfSet flag action | flag = action
187 | otherwise = return ()
189 doIfSet_dyn :: DynFlags -> DynFlag -> IO () -> IO()
190 doIfSet_dyn dflags flag action | dopt flag dflags = action
191 | otherwise = return ()
193 -- -----------------------------------------------------------------------------
196 dumpIfSet :: Bool -> String -> SDoc -> IO ()
197 dumpIfSet flag hdr doc
198 | not flag = return ()
199 | otherwise = printDump (mkDumpDoc hdr doc)
201 dumpIf_core :: Bool -> DynFlags -> DynFlag -> String -> SDoc -> IO ()
202 dumpIf_core cond dflags dflag hdr doc
204 || verbosity dflags >= 4
205 || dopt Opt_D_verbose_core2core dflags
206 = dumpSDoc dflags dflag hdr doc
208 | otherwise = return ()
210 dumpIfSet_core :: DynFlags -> DynFlag -> String -> SDoc -> IO ()
211 dumpIfSet_core dflags flag hdr doc
212 = dumpIf_core (dopt flag dflags) dflags flag hdr doc
214 dumpIfSet_dyn :: DynFlags -> DynFlag -> String -> SDoc -> IO ()
215 dumpIfSet_dyn dflags flag hdr doc
216 | dopt flag dflags || verbosity dflags >= 4
217 = dumpSDoc dflags flag hdr doc
221 dumpIfSet_dyn_or :: DynFlags -> [DynFlag] -> String -> SDoc -> IO ()
222 dumpIfSet_dyn_or dflags flags hdr doc
223 | or [dopt flag dflags | flag <- flags]
224 || verbosity dflags >= 4
225 = printDump (mkDumpDoc hdr doc)
226 | otherwise = return ()
228 mkDumpDoc :: String -> SDoc -> SDoc
231 line <+> text hdr <+> line,
235 line = text (replicate 20 '=')
238 -- | Write out a dump.
239 -- If --dump-to-file is set then this goes to a file.
240 -- otherwise emit to stdout.
241 dumpSDoc :: DynFlags -> DynFlag -> String -> SDoc -> IO ()
242 dumpSDoc dflags dflag hdr doc
243 = do let mFile = chooseDumpFile dflags dflag
245 -- write the dump to a file
246 -- don't add the header in this case, we can see what kind
247 -- of dump it is from the filename.
249 -> do handle <- openFile fileName AppendMode
250 hPrintDump handle doc
253 -- write the dump to stdout
255 -> do printDump (mkDumpDoc hdr doc)
258 -- | Choose where to put a dump file based on DynFlags
260 chooseDumpFile :: DynFlags -> DynFlag -> Maybe String
261 chooseDumpFile dflags dflag
263 -- dump file location is being forced
264 -- by the --ddump-file-prefix flag.
266 , Just prefix <- dumpPrefixForce dflags
267 = Just $ prefix ++ (beautifyDumpName dflag)
269 -- dump file location chosen by DriverPipeline.runPipeline
271 , Just prefix <- dumpPrefix dflags
272 = Just $ prefix ++ (beautifyDumpName dflag)
274 -- we haven't got a place to put a dump file.
278 where dumpToFile = dopt Opt_DumpToFile dflags
281 -- | Build a nice file name from name of a DynFlag constructor
282 beautifyDumpName :: DynFlag -> String
283 beautifyDumpName dflag
284 = let str = show dflag
285 cut = if isPrefixOf "Opt_D_" str
288 dash = map (\c -> case c of
295 -- -----------------------------------------------------------------------------
296 -- Outputting messages from the compiler
298 -- We want all messages to go through one place, so that we can
299 -- redirect them if necessary. For example, when GHC is used as a
300 -- library we might want to catch all messages that GHC tries to
301 -- output and do something else with them.
303 ifVerbose :: DynFlags -> Int -> IO () -> IO ()
304 ifVerbose dflags val act
305 | verbosity dflags >= val = act
306 | otherwise = return ()
308 putMsg :: DynFlags -> Message -> IO ()
309 putMsg dflags msg = log_action dflags SevInfo noSrcSpan defaultUserStyle msg
311 errorMsg :: DynFlags -> Message -> IO ()
312 errorMsg dflags msg = log_action dflags SevError noSrcSpan defaultErrStyle msg
314 fatalErrorMsg :: DynFlags -> Message -> IO ()
315 fatalErrorMsg dflags msg = log_action dflags SevFatal noSrcSpan defaultErrStyle msg
317 compilationProgressMsg :: DynFlags -> String -> IO ()
318 compilationProgressMsg dflags msg
319 = ifVerbose dflags 1 (log_action dflags SevInfo noSrcSpan defaultUserStyle (text msg))
321 showPass :: DynFlags -> String -> IO ()
323 = ifVerbose dflags 2 (log_action dflags SevInfo noSrcSpan defaultUserStyle (text "***" <+> text what <> colon))
325 debugTraceMsg :: DynFlags -> Int -> Message -> IO ()
326 debugTraceMsg dflags val msg
327 = ifVerbose dflags val (log_action dflags SevInfo noSrcSpan defaultDumpStyle msg)