[GHC] #15537: Panic when building Crucible

[GHC]

#15537: Panic when building Crucible
-------------------------------------+-------------------------------------
           Reporter:  siddharthist   |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:  8.6.1
          Component:  Compiler       |           Version:  8.4.3
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  Compile-time
  Unknown/Multiple                   |  crash or panic
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
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 I've encountered a panic, which GHC has asked me to report:
 {{{
 [19 of 21] Compiling Lang.Crucible.LLVM.Translation (
 src/Lang/Crucible/LLVM/Translation.hs,
 dist/build/Lang/Crucible/LLVM/Translation.p_o )

 <no location info>: error:
     ghc: panic! (the 'impossible' happened)
   (GHC version 8.4.3 for x86_64-unknown-linux):
         isUnliftedType
   r_a4Zsg :: TYPE rep_a4Zsf
   Call stack:
       CallStack (from HasCallStack):
         callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in
 ghc:Outputable
         pprPanic, called at compiler/types/Type.hs:1939:10 in ghc:Type

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

 }}}
 This was when compiling [https://github.com/GaloisInc/crucible/tree/master
 /crucible-llvm crucible-llvm] revision 186mfb7wlz with GHC 8.4.3.

 I'm building in Nix with a sandbox, so this should be easily reproducible.
 The Nix files are available here: https://github.com/siddharthist/galois-
 haskell-nix/tree/ghc-bug. Just run nix-build -A haskellPackages.crucible-
 llvm.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15537>
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