dataConInfoPtrToName doesn't correctly resolve constructors with a trailing .
I believe the parse
helper in dataConInfoPtrToName
in ghci/Linker.lhs
doesn't correctly parse data constructors that feature a trailing .
in the name.
Test case:
module X where
data X = Int :-> Int
| Int :->. Int
The second constructor (:->.
) will exhibit this bug.
Program to show the bug (in the same directory, needs ghc-paths from hackage):
{-# LANGUAGE BangPatterns #-}
module Main where
import ByteCodeLink
import CoreMonad
import Data.Array
import DataCon
import GHC
import HscTypes
import Linker
import RtClosureInspect
import GHC.Paths
import TcEnv
import Type
import TcRnMonad
import TcType
import Control.Applicative
import Name (getOccString)
import Unsafe.Coerce
import Control.Monad
import Data.Maybe
import Bag
import PrelNames (iNTERACTIVE)
import Outputable
import X
main :: IO ()
main = runGhc (Just libdir) $ do
dflags' <- getSessionDynFlags
primPackages <- setSessionDynFlags dflags'
dflags <- getSessionDynFlags
defaultCleanupHandler dflags $ do
target <- guessTarget "X.hs" Nothing
setTargets [target]
load LoadAllTargets
() <- chaseConstructor (unsafeCoerce False)
() <- chaseConstructor (unsafeCoerce [1,2,3])
() <- chaseConstructor (unsafeCoerce (3 :-> 2))
() <- chaseConstructor (unsafeCoerce (4 :->. 4))
return ()
chaseConstructor :: (GhcMonad m) => HValue -> m ()
chaseConstructor !hv = do
closure <- liftIO $ getClosureData hv
case tipe closure of
Indirection _ -> chaseConstructor (ptrs closure ! 0)
Constr -> do
withSession $ \hscEnv -> liftIO $ initTcForLookup hscEnv $ do
eDcname <- dataConInfoPtrToName (infoPtr closure)
case eDcname of
Left _ -> return ()
Right dcName -> do
liftIO $ putStrLn $ "Name: " ++ showPpr dcName
liftIO $ putStrLn $ "OccString: " ++ "'" ++ getOccString dcName ++ "'"
dc <- tcLookupDataCon dcName
liftIO $ putStrLn $ "DataCon: " ++ showPpr dc
_ -> return ()
initTcForLookup :: HscEnv -> TcM a -> IO a
initTcForLookup hsc_env = liftM (\(msg, mValue) -> fromMaybe (error . show . bagToList . snd $ msg) mValue) . initTc hsc_env HsSrcFile False iNTERACTIVE
Under 6.12.1, this outputs:
>./Main
Name: GHC.Bool.False
OccString: 'False'
DataCon: GHC.Bool.False
Name: :
OccString: ':'
DataCon: :
Name: X.:->
OccString: ':->'
DataCon: X.:->
Name: X.:->.
OccString: ''
Main: [Failed to load interface for `X.:->':
Use -v to see a list of the files searched for.]
Note in the last case it's trying to load the interface for :-> (not :->.), and the OccString hasn't correctly been resolved.
Trac metadata
Trac field | Value |
---|---|
Version | 6.12.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |