[GHC] #12660: singletons doesn't compile with GHC 8.0.2 snapshot

[GHC]

#12660: singletons doesn't compile with GHC 8.0.2 snapshot
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        Reporter:  bgamari           |                Owner:
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.0.2
       Component:  Compiler          |              Version:
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 I quickly built a new profiled compiler and built `singletons` which
 revealed,
 {{{
 stack overflow: use +RTS -K<size> to increase it
 *** Exception (reporting due to +RTS -xc): (THUNK_1_0), stack trace:
   GHC.defaultErrorHandler.\,
   called from TcCanonical.canEvVar,
   called from TcInteract.solve_loop,
   called from TcInteract.solveSimples,
   called from TcRnDriver.simplifyTop,
   called from TcRnDriver.tcRnSrcDecls,
   called from HscMain.Typecheck-Rename,
   called from GhcMake.upsweep_mod.compile_it,
   called from GhcMake.upsweep_mod,
   called from GhcMake.upsweep.upsweep',
   called from GhcMake.upsweep,
   called from GhcMake.load,
   called from GHC.withCleanupSession,
   called from GHC.runGhc,
   called from GHC.defaultErrorHandler
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12660#comment:1>
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