[GHC] #7965: The 'impossible' happened!

[GHC]

#7965: The 'impossible' happened!
-------------------------------+--------------------------------------------
Reporter:  adit                |          Owner:                
    Type:  bug                 |         Status:  new           
Priority:  normal              |      Component:  Compiler      
 Version:  7.4.1               |       Keywords:                
      Os:  MacOS X             |   Architecture:  x86_64 (amd64)
 Failure:  Compile-time crash  |      Blockedby:                
Blocking:                      |        Related:                
-------------------------------+--------------------------------------------
 I'm working on a haskell package (code here:
 https://github.com/egonschiele/rdioh) and when I try to build it I get
 this error consistently:

 In order, the following will be installed:
 rdioh-0.1.1 (reinstall) changes: hspec-1.4.4 added
 Warning: Note that reinstalls are always dangerous. Continuing anyway...
 Configuring rdioh-0.1.1...
 Building rdioh-0.1.1...
 Preprocessing executable 'rdioh' for rdioh-0.1.1...
 [2 of 5] Compiling Rdioh.Models     ( src/Rdioh/Models.hs,
 dist/build/rdioh/rdioh-tmp/Rdioh/Models.o )
 ghc: panic! (the 'impossible' happened)
   (GHC version 7.4.1 for x86_64-apple-darwin):
         nameModule show{tv a1rK}

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

 Failed to install rdioh-0.1.1
 cabal: Error: some packages failed to install:
 rdioh-0.1.1 failed during the building phase. The exception was:
 ExitFailure 1
 make: *** [all] Error 1


 I'm on OSX v 10.8.2. Darwin Kernel Version 12.2.1: Thu Oct 18 12:13:47 PDT
 2012; root:xnu-2050.20.9~1/RELEASE_X86_64 x86_64

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7965>
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