[GHC] #8132: Warning for Typeable instances misplaced

[GHC]

#8132: Warning for Typeable instances misplaced
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        Reporter:  scottgw                       |            Owner:
            Type:  bug                           |  dreixel
        Priority:  normal                        |           Status:  new
       Component:  Compiler                      |        Milestone:
      Resolution:                                |          Version:  7.7
Operating System:  Unknown/Multiple              |         Keywords:
 Type of failure:  Incorrect warning at          |     Architecture:
  compile-time                                   |  Unknown/Multiple
       Test Case:                                |       Difficulty:
        Blocking:                                |  Unknown
                                                 |       Blocked By:
                                                 |  Related Tickets:
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Comment (by simonpj):

 I think we should turn the warning into an error.  We really, really don't
 want hand-written `Typeable` instances.  If there are any, we should just
 report an error.  Making it into an error rather than a warning will
 ensure that it is displayed even if there are other errors.  (Indeed, if
 there are errors in the instances, we may not even proceed to typecheck
 the value declarations at all... I'm not sure.)

 Pedro, would you be up for making that (easy) change?  Thanks.

 Simon

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8132#comment:3>
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