[GHC] #13740: GHC panic with operator constructor of newtype

[GHC]

#13740: GHC panic with operator constructor of newtype
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        Reporter:  codebje           |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler (Type    |              Version:  8.0.2
  checker)                           |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Compile-time      |  Unknown/Multiple
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  13741             |  Differential Rev(s):
       Wiki Page:                    |
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Changes (by codebje):

 * related:   => 13741


Comment:

 Duplicated in https://ghc.haskell.org/trac/ghc/ticket/13741#ticket.

 The issue is not triggered if precedence and fixity are assigned:

 {{{
 infixl 5 >>-    -- any precedence and fixity works
 newtype Cont r a = Cont { (>>-) :: (a -> r) -> r }
 x = \a b c -> c >>- a . b
 }}}

 Other infix operators in place of `.` don't seem to cause the same
 problem, but that's not an exhaustive check!

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13740#comment:1>
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