[GHC] #10684: Error cascade when unrelated class derivation fails

[GHC]

#10684: Error cascade when unrelated class derivation fails
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        Reporter:  ezyang            |                Owner:
            Type:  bug               |               Status:  new
        Priority:  low               |            Milestone:
       Component:  Compiler (Type    |              Version:  7.11
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by RyanGlScott):

 * cc: RyanGlScott (added)


Comment:

 Since all datatypes now have `Typeable` derived implicitly, here's a
 modern version of this bug:

 {{{#!hs
 module A where
 import GHC.Generics
 data A = A deriving (Show, Generic)
 data B = B A deriving (Show)
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10684#comment:1>
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