[GHC] #16112: T11334b fails in the devel2 way

[GHC]

#16112: T11334b fails in the devel2 way
-------------------------------------+-------------------------------------
           Reporter:  bgamari        |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  high           |         Milestone:  8.8.1
          Component:  Compiler       |           Version:  8.6.3
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 {{{patch
 --- dependent/should_fail/T11334b.run/T11334b.stderr.normalised 2018-12-30
 16:00:25.377677569 +0000
 +++ dependent/should_fail/T11334b.run/T11334b.comp.stderr.normalised
 2018-12-30 16:00:25.377677569 +0000
 @@ -1,24 +1,13 @@
 +ghc: panic! (the 'impossible' happened)
 +  (GHC version 8.7.20181230 for x86_64-unknown-linux):
 +       ASSERT failed!
 +  f_aBF[tau:2]
 +  2
 +  1
 +  Call stack:
 +      CallStack (from HasCallStack):
 +        callStackDoc, called at
 compiler/utils/Outputable.hs:<line>:<column> in <package-id>:Outputable
 +        pprPanic, called at compiler/utils/Outputable.hs:<line>:<column>
 in <package-id>:Outputable
 +        assertPprPanic, called at
 compiler/typecheck/TcType.hs:<line>:<column> in <package-id>:TcType

 -T11334b.hs:8:14:
 -     Cannot default kind variable ‘f0’
 -      of kind: k0 -> *
 -      Perhaps enable PolyKinds or add a kind signature
 -     In an expression type signature: Proxy 'Compose
 -      In the expression: Proxy :: Proxy 'Compose
 -      In an equation for ‘p’: p = Proxy :: Proxy 'Compose
 -
 -T11334b.hs:8:14:
 -     Cannot default kind variable ‘g0’
 -      of kind: k10 -> k0
 -      Perhaps enable PolyKinds or add a kind signature
 -     In an expression type signature: Proxy 'Compose
 -      In the expression: Proxy :: Proxy 'Compose
 -      In an equation for ‘p’: p = Proxy :: Proxy 'Compose
 -
 -T11334b.hs:8:14:
 -     Cannot default kind variable ‘a0’
 -      of kind: k10
 -      Perhaps enable PolyKinds or add a kind signature
 -     In an expression type signature: Proxy 'Compose
 -      In the expression: Proxy :: Proxy 'Compose
 -      In an equation for ‘p’: p = Proxy :: Proxy 'Compose
 +Please report this as a GHC bug:  https://www.haskell.org/ghc/reportabug
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16112>
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