[GHC] #10245: panic in new integer switch logic with "out-of-range" literals

[GHC]

#10245: panic in new integer switch logic with "out-of-range" literals
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        Reporter:  rwbarton          |                Owner:  AndreasK
            Type:  bug               |               Status:  patch
        Priority:  normal            |            Milestone:  8.2.1
       Component:  Compiler          |              Version:  7.11
  (CodeGen)                          |
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:  x86_64
 Type of failure:  Incorrect result  |  (amd64)
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  Phab:D4218
       Wiki Page:                    |
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Changes (by AndreasK):

 * status:  new => patch


Comment:

 I have a patch up on Phab but it increases allocations. (Phab:D4218)

 This seems to be caused by desugaring of derived constants.
 While the constants should be safe I don't see a way to differentiate them
 from user written constants.

 So I would appreciate input on the issue.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10245#comment:17>
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