[GHC] #7235: "panic!" when compiling happstack-server-7.0.4

[GHC]

#7235: "panic!" when compiling happstack-server-7.0.4
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        Reporter:  guest                      |            Owner:
            Type:  bug                        |           Status:  closed
        Priority:  normal                     |        Milestone:
       Component:  Compiler                   |          Version:  7.4.2
      Resolution:  duplicate                  |         Keywords:
Operating System:  Linux                      |     Architecture:
 Type of failure:  GHC rejects valid program  |  Unknown/Multiple
       Test Case:                             |       Difficulty:  Unknown
        Blocking:                             |       Blocked By:
                                              |  Related Tickets:
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Comment (by ivan.perez):

 I understand that this is an old, closed ticket, but I'm hitting this when
 I try to compile a package. I'm not sure it's the same bug.

 I'm on Ubuntu 12.10, I'm adding the package list that cabal selects so
 that you have more information about what I'm using. This is a fresh-new
 installation: I removed my .ghc and .cabal dirs before compiling this.


 {{{
 Configuring postgresql-simple-0.3.7.1...
 Building postgresql-simple-0.3.7.1...
 Preprocessing library postgresql-simple-0.3.7.1...

 [...removed by me...]

 [26 of 32] Compiling Database.PostgreSQL.Simple.FromField (
 src/Database/PostgreSQL/Simple/FromField.hs,
 dist/build/Database/PostgreSQL/Simple/FromField.o )
 Loading package ghc-prim ... linking ... done.
 Loading package integer-gmp ... linking ... done.
 Loading package base ... linking ... done.
 Loading package array-0.4.0.1 ... linking ... done.
 Loading package deepseq-1.3.0.1 ... linking ... done.
 Loading package bytestring-0.10.2.0 ... linking ... done.
 Loading package postgresql-libpq-0.8.2.4 ... linking ... done.
 Loading package text-0.11.3.1 ... linking ... done.
 Loading package blaze-builder-0.3.1.1 ... linking ... done.
 Loading package old-locale-1.0.0.5 ... linking ... done.
 Loading package time-1.4.1 ... linking ... done.
 Loading package primitive-0.5.0.1 ... linking ... done.
 Loading package vector-0.10.0.1 ... linking ... done.
 Loading package blaze-textual-0.2.0.8 ... linking ... done.
 Loading package containers-0.5.3.1 ... linking ... done.
 Loading package attoparsec-0.10.4.0 ... linking ... done.
 Loading package dlist-0.5 ... linking ... done.
 Loading package hashable-1.1.2.5 ... linking ... done.
 Loading package transformers-0.3.0.0 ... linking ... done.
 Loading package mtl-2.1.2 ... linking ... done.
 Loading package syb-0.3.7 ... linking ... done.
 Loading package pretty-1.1.1.0 ... linking ... done.
 Loading package template-haskell ... linking ... done.
 Loading package unordered-containers-0.2.3.2 ... linking ... done.
 Loading package aeson-0.6.2.0 ... linking ... done.

 src/Database/PostgreSQL/Simple/FromField.hs:485:11:ghc: panic! (the
 'impossible' happened)
   (GHC version 7.4.2 for x86_64-unknown-linux):
         Can't happen: pprExp (CompExp [])
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/7235#comment:3>
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