[GHC] #14051: Unboxed sums-related panic: getUnboxedSumName 513

[GHC]

#14051: Unboxed sums-related panic: getUnboxedSumName 513
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        Reporter:  RyanGlScott       |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  Compiler          |              Version:  8.2.1-rc2
      Resolution:                    |             Keywords:  UnboxedSums
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 RyanGlScott):

 * cc: bgamari (added)
 * failure:  GHC accepts invalid program => None/Unknown
 * component:  Compiler (Type checker) => Compiler


Comment:

 The fact that the code in `Main` doesn't typecheck is unimportant, since
 you can also trigger the panic with this code that does typecheck:

 {{{#!hs
 -- Bug.hs
 {-# LANGUAGE UnboxedSums #-}

 module Main where

 import Testing

 main :: IO ()
 main = print $ case func () of
   (# True | #) -> 123
   _ -> 321
 }}}

 cc'ing Ben, who wrote the `getUnboxedSumName` function in
 34d933d6a821edf5abfcbee76d9325362fc28a13.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14051#comment:2>
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