[GHC] #12835: ghc: panic! (the 'impossible' happened) - find_tycon

[GHC]

#12835: ghc: panic! (the 'impossible' happened) - find_tycon
-------------------------------------+-------------------------------------
           Reporter:  mrijkeboer     |             Owner:
               Type:  bug            |            Status:  new
           Priority:  high           |         Milestone:
          Component:  Compiler       |           Version:  8.0.1
           Keywords:                 |  Operating System:  Linux
       Architecture:  x86_64         |   Type of failure:  Compile-time
  (amd64)                            |  crash or panic
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 {{{
 $ stack build
 server-0.0.0.1: build

 --  While building package server-0.0.0.1 using:
       /home/martijn/.stack/setup-exe-cache/x86_64-linux/setup-Simple-
 Cabal-1.24.0.0-ghc-8.0.1 --builddir=.stack-
 work/dist/x86_64-linux/Cabal-1.24.0.0 build lib:server exe:server --ghc-
 options " -ddump-hi -ddump-to-file"
     Process exited with code: ExitFailure 1
     Logs have been written to: /home/martijn/server/.stack-
 work/logs/server-0.0.0.1.log

     Preprocessing library server-0.0.0.1...
     [20 of 20] Compiling Application      ( src/Application.hs, .stack-
 work/dist/x86_64-linux/Cabal-1.24.0.0/build/Application.o )
     ghc: panic! (the 'impossible' happened)
       (GHC version 8.0.1 for x86_64-unknown-linux):
         find_tycon
       YesodSubRunnerEnv
       []

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

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12835>
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