[GHC] #10388: GHC panic when compiling Yesod app

[GHC]

#10388: GHC panic when compiling Yesod app
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              Reporter:  chfi        |             Owner:
                  Type:  bug         |            Status:  new
              Priority:  normal      |         Milestone:
             Component:  Compiler    |           Version:  7.10.1
              Keywords:              |  Operating System:  MacOS X
          Architecture:  x86_64      |   Type of failure:  Compile-time
  (amd64)                            |  crash
             Test Case:              |        Blocked By:
              Blocking:              |   Related Tickets:
Differential Revisions:              |
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 When compiling a Yesod app, using 'yesod devel', GHC crashes with the
 following error:


 {{{
 <no location info>:
     ghc: panic! (the 'impossible' happened)
   (GHC version 7.10.1 for x86_64-apple-darwin):
         Loading temp shared object failed:
 dlopen(/var/folders/yb/98yhr6bj5fg3z68prq2gxs6w0000gn/T/ghc99761_0/libghc99761_51.dylib,
 5): Symbol not found:
 _adverzuGWP0VNzzhgmvBNANratclKO_SubscriptionType_zdfPersistFieldKey_closure
   Referenced from:
 /var/folders/yb/98yhr6bj5fg3z68prq2gxs6w0000gn/T/ghc99761_0/libghc99761_51.dylib
   Expected in: flat namespace
  in
 /var/folders/yb/98yhr6bj5fg3z68prq2gxs6w0000gn/T/ghc99761_0/libghc99761_51.dylib
 }}}

 Specifically, I'm using Yesod's mkPersist to create a data type,
 and it works fine, until I make said type an instance of FromJSON, in
 which case the above panic occurs.

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10388>
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