[GHC] #15037: Running 1 twice, followed by a typed hole, in GHCi causes internal error

14 Apr 2018

      #15037: Running 1 twice, followed by a typed hole, in GHCi causes internal error
-------------------------------------+-------------------------------------
           Reporter:  RyanGlScott    |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:  8.6.1
          Component:  GHCi           |           Version:  8.5
           Keywords:  TypedHoles     |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  Compile-time
  Unknown/Multiple                   |  crash or panic
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 Originally reported in
 https://ghc.haskell.org/trac/ghc/ticket/14996#comment:2. You need GHC HEAD
 (i.e., more recent than GHC 8.4.1) to trigger this:

 {{{
 $ inplace/bin/ghc-stage2 --interactive
 GHCi, version 8.5.20180413: http://www.haskell.org/ghc/  :? for help
 Loaded GHCi configuration from /home/rgscott/.ghci
 λ> 1
 1
 λ> 1
 1
 λ> _

 <interactive>:1:1: error:
     GHC internal error: ‘Ghci1.it’ is not in scope during type checking,
 but it passed the renamer
     tcl_env of environment: []
 }}}

 And yes, running `1` //twice// seems to be critical to triggering this
 bug, for some reason.

-- 
Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15037
GHC http://www.haskell.org/ghc/
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