[GHC] #6013: the 'impossible' happened

[GHC]

#6013: the 'impossible' happened
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  Reporter:  tlvb                     |          Owner:                                          
      Type:  bug                      |         Status:  closed                                  
  Priority:  normal                   |      Milestone:  7.6.1                                   
 Component:  Compiler (Type checker)  |        Version:  7.4.1                                   
Resolution:  duplicate                |       Keywords:  panic, impossible, type checker, renamer
        Os:  Linux                    |   Architecture:  x86_64 (amd64)                          
   Failure:  Compile-time crash       |     Difficulty:  Unknown                                 
  Testcase:                           |      Blockedby:                                          
  Blocking:                           |        Related:  #5961                                   
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Changes (by pcapriotti):

  * status:  new => closed
  * failure:  GHCi crash => Compile-time crash
  * related:  => #5961
  * difficulty:  => Unknown
  * milestone:  => 7.6.1
  * resolution:  => duplicate


Comment:

 Thanks for the report.

 The problem in the code is that `Show` should be capitalized (in the
 deriving clause of the definition of `Machine`).

 However, you're right that GHC should report the error instead of
 crashing. This is actually a duplicate of #5961, and fixed in HEAD.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/6013#comment:1>
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