[GHC] #15755: randomRIO panic on (GHC version 8.4.3 for x86_64-apple-darwin)

[GHC]

#15755: randomRIO panic on (GHC version 8.4.3 for x86_64-apple-darwin)
-------------------------------------+-------------------------------------
        Reporter:  cmal              |                Owner:  (none)
            Type:  bug               |               Status:  infoneeded
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.4.3
      Resolution:                    |             Keywords:  randomRIO
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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Changes (by bgamari):

 * status:  new => infoneeded


Old description:

>  randomRIO (1,100)
> ghc: panic! (the 'impossible' happened)
>   (GHC version 8.4.3 for x86_64-apple-darwin):
>         nameModule
>   system $dShow_a78p
>   Call stack:
>       CallStack (from HasCallStack):
>         callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in
> ghc:Outputable
>         pprPanic, called at compiler/basicTypes/Name.hs:241:3 in ghc:Name
>
> Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug

New description:

 randomRIO (1,100)
 ghc: panic! (the 'impossible' happened)
   (GHC version 8.4.3 for x86_64-apple-darwin):
         nameModule
   system $dShow_a78p
   Call stack:
       CallStack (from HasCallStack):
         callStackDoc, called at compiler/utils/Outputable.hs:1150:37 in
 ghc:Outputable
         pprPanic, called at compiler/basicTypes/Name.hs:241:3 in ghc:Name

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

--

Comment:

 Can you provide more specific reproduction instructions?

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15755#comment:1>
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