[GHC] #11456: Type application and :set +c command cause panic

18 Jan 2016


      #11456: Type application and :set +c command cause panic
-------------------------------------+-------------------------------------
           Reporter:  Iceland_jack   |             Owner:
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:
          Component:  Compiler       |           Version:  8.1
           Keywords:                 |  Operating System:  Unknown/Multiple
  TypeApplications GHCi              |
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 Type applications and the [https://downloads.haskell.org/~ghc/master
 /users-guide/ghci.html#ghci-cmd-:set%20+c :set +c] command don't play nice

 {{{#!hs
 {-# LANGUAGE TypeApplications #-}
 a = show @Int
 }}}

 {{{
 % ghci -ignore-dot-ghci
 GHCi, version 8.1.20160117: http://www.haskell.org/ghc/  :? for help
 Prelude> :set +c
 Prelude> :load Panic.hs
 [1 of 1] Compiling Main             ( Panic.hs, interpreted )
 Ok, modules loaded: Main.
 Collecting type info for 1 module(s) ...
 Error while getting type info from Main: ghc: panic! (the 'impossible'
 happened)
   (GHC version 8.1.20160117 for x86_64-unknown-linux):
         dsExpr:HsTypeOut

 Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

 *Main>
 }}}

--
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11456
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