[GHC] #8777: Ghc crashes when compiling happstack-server on ubuntu-docker

[GHC]

#8777: Ghc crashes when compiling happstack-server on ubuntu-docker
------------------------------------+-------------------------------------
       Reporter:  timthelion        |             Owner:
           Type:  bug               |            Status:  new
       Priority:  low               |         Milestone:
      Component:  Compiler          |           Version:  7.4.1
       Keywords:                    |  Operating System:  Unknown/Multiple
   Architecture:  Unknown/Multiple  |   Type of failure:  None/Unknown
     Difficulty:  Unknown           |         Test Case:
     Blocked By:                    |          Blocking:
Related Tickets:                    |
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 I am trying to install a package that requires happstack on docker.  I
 recieved the following error:

 {{{
 src/Happstack/Server/Internal/Socket.hs:61:7:ghc: panic! (the 'impossible'
 happened)
   (GHC version 7.4.1 for x86_64-unknown-linux):
         Can't happen: pprExp (CompExp [])

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

 It appears I am not the first to receive this error as I found the
 following paste on lpaste: http://lpaste.net/report/99343

 This bug is hard to reproduce.  I tried making a minimal case for it in
 which only haskell-platform was installed.  In the minimal case, ghc DOES
 NOT crash.

 This works:
 {{{
 FROM ubuntu
 RUN apt-get update
 RUN apt-get install -y haskell-platform
 RUN cabal update
 RUN cabal install --global happstack-server-7.3.3
 }}}


 However, if you run the following docker file, ghc will crash:
 {{{
 FROM ubuntu
 RUN apt-get update
 RUN apt-get install -y haskell-platform git libghc-terminfo-dev libghc-
 haskeline-dev
 RUN cabal update
 RUN git clone --branch dev https://github.com/evancz/Elm.git
 RUN git clone --branch dev https://github.com/evancz/elm-repl.git
 RUN git clone  https://github.com/evancz/elm-get.git
 RUN cd Elm; git checkout a815b2fbd00e76c0109b1ab916fe5d0eb184648c
 RUN cd elm-repl; git checkout 6ab74981363e8e7fabc05083539891568e3c4f17
 RUN cd elm-get ; git checkout c67a8ba285f6bfde0a520da1552c4c3443cfab8e
 RUN cabal install --global Elm elm-repl elm-get Elm/server
 }}}


 Crashes with attached output.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/8777>
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