[GHC] #2310: Panic in ghci 6.8.2 with -fglasgow-exts

[GHC]

#2310: Panic in ghci 6.8.2 with -fglasgow-exts
--------------------+-------------------------------------------------------
 Reporter:  guest   |          Owner:             
     Type:  bug     |         Status:  new        
 Priority:  normal  |      Milestone:  6.10 branch
Component:  GHCi    |        Version:  6.8.2      
 Severity:  normal  |     Resolution:             
 Keywords:          |     Difficulty:  Unknown    
 Testcase:          |   Architecture:  x86        
       Os:  Linux   |  
--------------------+-------------------------------------------------------
Changes (by igloo):

  * difficulty:  => Unknown
  * milestone:  => 6.10 branch

Comment:

 Thanks for the report. Also happens in the HEAD. Here's a smaller example:
 {{{
 $ ghci -XScopedTypeVariables -XPatternSignatures -v0
 Prelude> let c = \ x :: a -> (x :: a)
 ghc-6.9.20080523: panic! (the 'impossible' happened)
   (GHC version 6.9.20080523 for x86_64-unknown-linux):
         nameModule a{tv am3}
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2310#comment:2>
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