[GHC] #15962: Type family & typeclass interaction suppresses errors

[GHC]

#15962: Type family & typeclass interaction suppresses errors
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        Reporter:  madgen            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  ⊥
       Component:  Compiler (Type    |              Version:  8.4.3
  checker)                           |             Keywords:  TypedHoles,
      Resolution:                    |  newcomer
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  error/warning at compile-time      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by Ryan Scott <ryan.gl.scott@…>):

 In [changeset:"8d7496c42f049578187c4e5be08963cb497c2fac/ghc" 8d7496c/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="8d7496c42f049578187c4e5be08963cb497c2fac"
 Add a test case for #15962

 Test Plan: make test TEST=T15962

 Reviewers: RyanGlScott, bgamari

 Reviewed By: RyanGlScott

 Subscribers: rwbarton, carter

 GHC Trac Issues: #15962

 Differential Revision: https://phabricator.haskell.org/D5393
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15962#comment:2>
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