[GHC] #14838: missing "incomplete-patterns" warning for TH-generated functions

[GHC]

#14838: missing "incomplete-patterns" warning for TH-generated functions
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        Reporter:  gelisam           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.10.1
       Component:  Template Haskell  |              Version:  8.2.2
      Resolution:                    |             Keywords:
                                     |  PatternMatchWarnings
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect         |  Unknown/Multiple
  error/warning at compile-time      |            Test Case:  T14838
      Blocked By:                    |             Blocking:
 Related Tickets:  #16169            |  Differential Rev(s):  Phab:D4440
       Wiki Page:                    |
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Comment (by RyanGlScott):

 For the sake of historical context, the original patch was in reverted in
 light of #14899, where it was discovered that the only reason that
 `singletons` compiles in a reasonable amount of time is because pattern-
 match coverage checking is disabled for generated code. Technically, the
 problem still exists if you were to write this code by hand, but we deemed
 `singletons` to be an important-enough reason not to keep the patch :)

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14838#comment:15>
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