[GHC] #1688: Attached file causes stack overflow

[GHC]

#1688: Attached file causes stack overflow
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    Reporter:  jgbailey at gmail.com  |        Owner:            
        Type:  bug                 |       Status:  new       
    Priority:  normal              |    Milestone:  6.8 branch
   Component:  Compiler            |      Version:  6.7       
    Severity:  normal              |   Resolution:            
    Keywords:                      |   Difficulty:  Unknown   
          Os:  Windows             |     Testcase:            
Architecture:  x86                 |  
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Changes (by simonpj):

  * milestone:  => 6.8 branch

Comment:

 Good bug.  Here is a much smaller module showing the same problem
 {{{
 newtype M s a = M a

 class Modular s a | s -> a

 wim ::  forall a w. Integral a
                       => a -> (forall s. Modular s a => M s w) -> w
 wim i k = error "urk"

 test4'  ::  (Modular s a, Integral a) => M s a
 test4'  =   error "urk"

 test4   =   wim 4 test4'
 }}}
 Also, removing the first parameter of `wim` gives an ASSERT failure.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1688>
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