[GHC] #6025: GHC Panic On Recompile

[GHC]

#6025: GHC Panic On Recompile
--------------------------------+-------------------------------------------
 Reporter:  scooty-puff         |          Owner:                  
     Type:  bug                 |         Status:  new             
 Priority:  normal              |      Component:  Compiler        
  Version:  7.4.1               |       Keywords:                  
       Os:  Unknown/Multiple    |   Architecture:  Unknown/Multiple
  Failure:  Compile-time crash  |       Testcase:                  
Blockedby:                      |       Blocking:                  
  Related:                      |  
--------------------------------+-------------------------------------------
 Perhaps related to DataKinds or ConstraintKinds, but on rebuild without a
 clean, the following error is emitted:


 Building glyph-0.1...
 Preprocessing executable 'glyph' for glyph-0.1...
 [34 of 60] Compiling Language.Glyph.HM.InferType (
 src/Language/Glyph/HM/InferType.hs, dist/build/glyph/glyph-
 tmp/Language/Glyph/HM/InferType.p_o )
 ghc: panic! (the 'impossible' happened)
   (GHC version 7.4.1 for x86_64-unknown-linux):
         tyThingTyCon
     Data constructor `main:Language.Glyph.Type.Normal{d r3iU}'

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

 This can be recreated by building this cabal project:

 https://github.com/sonyandy/glyph/tree/ghc-panic

 To recreate:

 git clone https://github.com/sonyandy/glyph/tree/ghc-panic

 cabal configure

 cabal build

 touch src/Language/Glyph/HM/InferType.hs

 cabal build

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/6025>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler