[GHC] #15617: Unboxed tuples/sum error message on `a = show 5` in expression evaluation and interactive modes

[GHC]

#15617: Unboxed tuples/sum error message on `a = show 5` in expression evaluation
and interactive modes
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        Reporter:  ChaiTRex          |                Owner:
                                     |  JulianLeviston
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.6.1-beta1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Poor/confusing    |  Unknown/Multiple
  error message                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by JulianLeviston):

 I *think* the problem is setting the `fobject-code` flag mean
 HscInterpreted won't ever get set,
 which means when checkOptLevel gets called, the error doesn't trigger,
 because it only works for HscInterpreted.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15617#comment:8>
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