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:history throws "Irrefutable pattern failed" exception

I am trying to use the GHCi debugger to find out why my code has a StackOverflow exception - but GHCi itself seems to be throwing an exception when I type :history:

(temp)[greenrd@localhost megaslurp]$ ghci Web.Twitter.Slurp               
GHCi, version 6.10.1: http://www.haskell.org/ghc/  :? for help            
Loading package ghc-prim ... linking ... done.                            
Loading package integer ... linking ... done.                             
Loading package base ... linking ... done.                                
[1 of 1] Compiling Web.Twitter.Slurp ( Web/Twitter/Slurp.hs, interpreted )
Loading package syb ... linking ... done.                                 
Loading package array-0.2.0.0 ... linking ... done.
Loading package packedstring-0.1.0.1 ... linking ... done.
Loading package containers-0.2.0.0 ... linking ... done.
Loading package pretty-1.0.1.0 ... linking ... done.
Loading package template-haskell ... linking ... done.
Loading package mtl-1.1.0.2 ... linking ... done.
Loading package filepath-1.1.0.1 ... linking ... done.
Loading package old-locale-1.0.0.1 ... linking ... done.
Loading package old-time-1.0.0.1 ... linking ... done.
Loading package unix-2.3.1.0 ... linking ... done.
Loading package directory-1.0.0.2 ... linking ... done.
Loading package process-1.0.1.0 ... linking ... done.
Loading package random-1.0.0.1 ... linking ... done.
Loading package derive-0.1.4 ... linking ... done.
Ok, modules loaded: Web.Twitter.Slurp.
*Web.Twitter.Slurp> :set -fbreak-on-error
*Web.Twitter.Slurp> :trace slurpRetry "/host/twitter-groups.csv"
Loading package base-3.0.3.0 ... linking ... done.
Loading package bytestring-0.9.1.4 ... linking ... done.
Loading package parsec-2.1.0.1 ... linking ... done.
Loading package network-2.2.0.1 ... linking ... done.
Loading package utf8-string-0.3.4 ... linking ... done.
Loading package json-0.4.3 ... linking ... done.
Loading package HTTP-4000.0.5 ... linking ... done.
Loading package binary-0.5.0.1 ... linking ... done.
Loading package mime-0.3.0 ... linking ... done.
Loading package csv-0.1.1 ... linking ... done.
Loading package hs-twitter-0.2.5 ... linking ... done.
Stopped at <exception thrown>
_exception ::
  e = GHC.Exception.SomeException (GHC.Exception.:DException _
                                                             (GHC.Show.:DShow ...) ....)
                                  GHC.IOBase.StackOverflow
[<exception thrown>] *Web.Twitter.Slurp> :history
*** Exception: main/InteractiveEval.hs:(179,13)-(183,46): Irrefutable pattern failed for pattern Data.Maybe.Just decl
Trac metadata
Trac field Value
Version 6.10.1
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component GHCi
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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