*** setup configure

Configuring vty-4.2.1.0...
Dependency array -any: using array-0.3.0.2
Dependency base ==4.*: using base-4.3.0.0
Dependency bytestring -any: using bytestring-0.9.1.8
Dependency containers -any: using containers-0.4.0.0
Dependency ghc-prim -any: using ghc-prim-0.2.0.0
Dependency mtl >=1.1.0.0 && <1.2: using mtl-1.1.1.1
Dependency parallel <2: using parallel-1.1.0.1
Dependency parsec >=2 && <4: using parsec-2.1.0.1
Dependency terminfo ==0.3.*: using terminfo-0.3.1.3
Dependency unix -any: using unix-2.4.1.0
Dependency utf8-string ==0.3.*: using utf8-string-0.3.6
Dependency vector-space ==0.5.*: using vector-space-0.5.9
Using Cabal-1.10.0.0 compiled by ghc-7.0
Using compiler: ghc-7.0.1
Using install prefix: /usr/local/tmp/archive/install
Binaries installed in: /usr/local/tmp/archive/install/bin
Libraries installed in:
/usr/local/tmp/archive/install/lib/vty-4.2.1.0/ghc-7.0.1
Private binaries installed in: /usr/local/tmp/archive/install/libexec
Data files installed in: /usr/local/tmp/archive/install/share/vty-4.2.1.0
Documentation installed in:
/usr/local/tmp/archive/install/share/doc/vty-4.2.1.0
Using alex version 2.3.3 found on system at: /usr/bin/alex
Using ar found on system at: /usr/bin/ar
Using c2hs version 0.16.0 found on system at: /usr/local/bin/c2hs
Using cpphs version 1.11 found on system at: /usr/local/bin/cpphs
Using ffihugs found on system at: /usr/local/bin/ffihugs
Using gcc version 4.4.5 found on system at: /usr/bin/gcc
Using ghc version 7.0.1 found on system at: /usr/local/bin/ghc
Using ghc-pkg version 7.0.1 found on system at: /usr/local/bin/ghc-pkg
No greencard found
Using haddock version 2.8.0 found on system at: /usr/local/bin/haddock
Using happy version 1.18.6 found on system at: /usr/local/bin/happy
No hmake found
Using hsc2hs version 0.67 found on system at: /usr/local/bin/hsc2hs
Using hscolour version 1.17 found on system at: /usr/local/bin/HsColour
Using hugs found on system at: /usr/local/bin/hugs
No jhc found
Using ld found on system at: /usr/bin/ld
No lhc found
No lhc-pkg found
No nhc98 found
Using pkg-config version 0.25 found on system at: /usr/bin/pkg-config
Using ranlib found on system at: /usr/bin/ranlib
Using strip found on system at: /usr/bin/strip
Using tar found on system at: /bin/tar
No uhc found

*** setup build

Creating dist/build (and its parents)
Creating dist/build/autogen (and its parents)
Preprocessing library vty-4.2.1.0...
Building vty-4.2.1.0...
Building library...
Creating dist/build (and its parents)
/usr/local/bin/ghc --make -package-name vty-4.2.1.0 -hide-all-packages -fbuilding-cabal-package -i -idist/build -isrc -idist/build/autogen -Idist/build/autogen -Idist/build -Icbits -optP-include -optPdist/build/autogen/cabal_macros.h -odir dist/build -hidir dist/build -stubdir dist/build -package-id array-0.3.0.2-197667a808e421fc275e1d8f73f58618 -package-id base-4.3.0.0-b91367e4fa5bd47d8e75958171ad21b7 -package-id bytestring-0.9.1.8-2e812324817b74c7c5038e2cb74d96a9 -package-id containers-0.4.0.0-5e5729c8cc8101038443c9bd0115af01 -package-id ghc-prim-0.2.0.0-0713122c5f9038c6f0355a37e294e054 -package-id mtl-1.1.1.1-119e9581a5b36cba380f4207cffdb596 -package-id parallel-1.1.0.1-605bb6eb4cae41637dba6fd28dead2b3 -package-id parsec-2.1.0.1-8cf1730a357add17c736b1e051cf3ab0 -package-id terminfo-0.3.1.3-7eceda12fa264e4046b114f6a2936edb -package-id unix-2.4.1.0-7a6f0bd0ef9ac3d459bc3c4ee924b0d6 -package-id utf8-string-0.3.6-0297e00f7e96ce90aabfa940706dd831 -package-id vector-space-0.5.9-15cb29fb0e17173d21395e96f7b9dde9 -O -funbox-strict-fields -Wall -fno-full-laziness -fspec-constr -XHaskell98 Graphics.Vty Graphics.Vty.Terminal Graphics.Vty.LLInput Graphics.Vty.Attributes Graphics.Vty.Inline Graphics.Vty.Picture Graphics.Vty.DisplayRegion Codec.Binary.UTF8.Width Data.Marshalling Data.Terminfo.Parse Data.Terminfo.Eval Graphics.Vty.DisplayAttributes Graphics.Vty.Image Graphics.Vty.Span Graphics.Vty.Terminal.Generic Graphics.Vty.Terminal.MacOSX Graphics.Vty.Terminal.XTermColor Graphics.Vty.Terminal.TerminfoBased
[ 1 of 18] Compiling Data.Terminfo.Parse ( src/Data/Terminfo/Parse.hs, dist/build/Data/Terminfo/Parse.o )
ghc: panic! (the 'impossible' happened)
  (GHC version 7.0.1 for i386-unknown-linux):
	dsLet: unlifted
    AbsBinds
    [a{tv a10w} [sk]]
    [$dEnum{v aZY} [lid]]
    [c{v aoG} [lid] <= [a{tv a10w} [sk]] c{v aZX} [lid]]
      c{v aoG} [lid]
        :: forall a{tv a10w} [sk].
           base:GHC.Enum.Enum{tc 22} a{tv a10w} [sk] =>
           a{tv a10w} [sk]
      [LclId]
      { {279:9-34}
        {279:9-34}
        !((c{v aZX} [lid] :: a{tv a10w} [sk]))
          = {279:14-34}
            {279:21}
            ((base:GHC.Base.${v 019} [gid]))
            @ ghc-prim:GHC.Types.Int{(w) tc 3J}
            @ a{tv a10w} [sk]
              ((base:GHC.Enum.toEnum{v rP} [gid[ClassOp]]) @ a{tv a10w} [sk]
                 $dEnum{v aZY} [lid])
              ((base:GHC.List.length{v r1H} [gid])
               @ ghc-prim:GHC.Types.Char{(w) tc 3o}
                 bytes{v aoE} [lid]) }
    EvBinds{{}}
    base:GHC.Base.>>={v 01P} [gid[ClassOp]]
      @ (parsec-2.1.0.1:Text.ParserCombinators.Parsec.Prim.GenParser{tc rcq}
           ghc-prim:GHC.Types.Char{(w) tc 3o}
           vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE})
      $dMonad{v a10x} [lid]
      @ vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}
      @ vty-4.2.1.0:Data.Terminfo.Parse.BuildResults{tc rku}
      (parsec-2.1.0.1:Text.ParserCombinators.Parsec.Prim.getState{v rcA} [gid]
         @ ghc-prim:GHC.Types.Char{(w) tc 3o}
         @ vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE})
      (\ (s{v aoH} [lid]
            :: vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}) ->
         case s{v aoH} [lid]
         {parsec-2.1.0.1:Text.ParserCombinators.Parsec.Prim.GenParser{tc rcq}
            ghc-prim:GHC.Types.Char{(w) tc 3o}
            vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}
            vty-4.2.1.0:Data.Terminfo.Parse.BuildResults{tc rku}}
         of (s{v aoH} [lid]
               :: vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE})
         { __DEFAULT ->
         letrec {
           s'{v aoI} [lid]
             :: vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}
           [LclId]
           s'{v aoI} [lid] =
             letrec {
               s'{v a10B} [lid]
                 :: vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}
               [LclId]
               s'{v a10B} [lid] =
                 let {
                   ds_d1hs{v} [lid] :: base:GHC.Word.Word8{tc 32U}
                   [LclId]
                   ds_d1hs{v} [lid] =
                     base:GHC.Num.+{v r24} [gid[ClassOp]]
                       @ base:GHC.Word.Word8{tc 32U}
                       $dNum{v a10z} [lid]
                       start_offset{v aoF} [lid]
                       (c{v aoG} [lid]
                          @ base:GHC.Word.Word8{tc 32U} $dEnum{v a10A} [lid]) } in
                 let {
                   ds_d1hu{v} [lid]
                     :: vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}
                   [LclId]
                   ds_d1hu{v} [lid] = s{v aoH} [lid] } in
                 case ds_d1hu{v} [lid]
                 {vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}}
                 of (wild_B1{v} [lid]
                       :: vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE})
                 { vty-4.2.1.0:Data.Terminfo.Parse.BuildState{d rkG} (ds_d1ht{v} [lid]
                                                                        :: base:GHC.Word.Word8{tc 32U}) ->
                 vty-4.2.1.0:Data.Terminfo.Parse.BuildState{v rON} [gid[DataCon]]
                   ds_d1hs{v} [lid]
                 }; } in
             s'{v a10B} [lid]; } in
         base:GHC.Base.>>{v 01Q} [gid[ClassOp]]
           @ (parsec-2.1.0.1:Text.ParserCombinators.Parsec.Prim.GenParser{tc rcq}
                ghc-prim:GHC.Types.Char{(w) tc 3o}
                vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE})
           $dMonad{v a10D} [lid]
           @ ghc-prim:GHC.Unit.(){(w) tc 40}
           @ vty-4.2.1.0:Data.Terminfo.Parse.BuildResults{tc rku}
           (parsec-2.1.0.1:Text.ParserCombinators.Parsec.Prim.setState{v rcM} [gid]
              @ vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}
              @ ghc-prim:GHC.Types.Char{(w) tc 3o}
              s'{v aoI} [lid])
           (base:GHC.Base.${v 019} [gid]
              @ vty-4.2.1.0:Data.Terminfo.Parse.BuildResults{tc rku}
              @ (parsec-2.1.0.1:Text.ParserCombinators.Parsec.Prim.GenParser{tc rcq}
                   ghc-prim:GHC.Types.Char{(w) tc 3o}
                   vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE}
                   vty-4.2.1.0:Data.Terminfo.Parse.BuildResults{tc rku})
              (base:GHC.Base.return{v 01T} [gid[ClassOp]]
                 @ (parsec-2.1.0.1:Text.ParserCombinators.Parsec.Prim.GenParser{tc rcq}
                      ghc-prim:GHC.Types.Char{(w) tc 3o}
                      vty-4.2.1.0:Data.Terminfo.Parse.BuildState{tc rkE})
                 $dMonad{v a10F} [lid]
                 @ vty-4.2.1.0:Data.Terminfo.Parse.BuildResults{tc rku})
              (vty-4.2.1.0:Data.Terminfo.Parse.$WBuildResults{v rOL} [gid[DataConWrapper]]
                 (base:GHC.Word.W#{(w) v 6x} [gid[DataCon]] __word 0)
                 (base:GHC.Base.build{v 05} [gid]
                    @ vty-4.2.1.0:Data.Terminfo.Parse.CapOp{tc rkS}
                    (\ (@ a{tv d1hp} [tv])
                       (c_d1hq{v} [lid]
                          :: vty-4.2.1.0:Data.Terminfo.Parse.CapOp{tc rkS}
                             -> a{tv d1hp} [tv]
                             -> a{tv d1hp} [tv])
                       (n_d1hr{v} [lid] :: a{tv d1hp} [tv]) ->
                       c_d1hq{v} [lid]
                         (vty-4.2.1.0:Data.Terminfo.Parse.$WBytes{v rOP} [gid[DataConWrapper]]
                            start_offset{v aoF} [lid]
                            (c{v aoG} [lid]
                               @ vty-4.2.1.0:Data.Terminfo.Parse.BytesLength{tc rlM}
                               $dEnum{v a10H} [lid]))
                         (base:GHC.Base.foldr{v 08} [gid]
                            @ vty-4.2.1.0:Data.Terminfo.Parse.CapOp{tc rkS}
                            @ a{tv d1hp} [tv]
                            c_d1hq{v} [lid]
                            n_d1hr{v} [lid]
                            (ghc-prim:GHC.Types.[]{(w) v 6n} [gid[DataCon]]
                               @ vty-4.2.1.0:Data.Terminfo.Parse.CapOp{tc rkS}))))
                 (ghc-prim:GHC.Types.[]{(w) v 6n} [gid[DataCon]]
                    @ vty-4.2.1.0:Data.Terminfo.Parse.ParamOp{tc rkM})))
         })

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug