[GHC] #15692: GHC panic from pattern synonyms + deferred type errors

[GHC]

#15692: GHC panic from pattern synonyms + deferred type errors
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        Reporter:  Iceland_jack      |                Owner:  (none)
            Type:  bug               |               Status:  merge
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.6.1
      Resolution:                    |             Keywords:
                                     |  PatternSynonyms
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Compile-time      |            Test Case:
  crash or panic                     |  patsyn/should_fail/T15692
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by simonpj):

 * status:  new => merge
 * testcase:   => patsyn/should_fail/T15692


Comment:

 Thanks.

 This fix could probably be merged.  It modifies a bit more code than I'd
 usually like in a patch-release, but I'm pretty confident.  And it
 validates of course.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15692#comment:4>
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