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ghc: panic! (the 'impossible' happened) when using lowercase eq/show in deriving

Compiling the following:

module Main where

data Tree a = Edge a | Node (Tree a) (Tree a) deriving (eq,show)

main10 = print $ Node (Edge 10) (Edge 20)

main = main10

Results in:

ghc: panic! (the 'impossible' happened)

(GHC version 7.4.1 for i386-unknown-linux):

nameModule eq{tv a9O}

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

Trac metadata
Trac field Value
Version 7.4.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
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Operating system
Architecture
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