[GHC] #7384: Panic "ctEvTerm" when using functional dependencies and PolyKinds

[GHC]

#7384: Panic "ctEvTerm" when using functional dependencies and PolyKinds
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 Reporter:  goldfire          |          Owner:                                  
     Type:  bug               |         Status:  new                             
 Priority:  normal            |      Component:  Compiler                        
  Version:  7.7               |       Keywords:  FunctionalDependencies PolyKinds
       Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple                
  Failure:  None/Unknown      |       Testcase:                                  
Blockedby:                    |       Blocking:                                  
  Related:                    |  
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Comment(by simonpj@…):

 commit 4dade857ec0b1655b6297191b9262eb5174eec87
 {{{
 Author: Simon Peyton Jones <simonpj at microsoft.com>
 Date:   Tue Nov 6 16:03:11 2012 +0000

     Make rewriteCtFlavor lazy in the coercion for Derived evidence

     I think I accidentally introduced this bug a month ago when
     refactoring. It's a bit non-obvious, but since Derived constraints
     have no evidence, we mustn't be strict in it.  Now there's a big
     comment to prevent this bug happening again.

     This fixes Trac #7384.

  compiler/typecheck/TcSMonad.lhs |   66
 ++++++++++++++++++++++-----------------
  1 files changed, 37 insertions(+), 29 deletions(-)
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7384#comment:2>
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