[GHC] #15570: Core transformations generate bad indexCharOffAddr# call

[GHC]

#15570: Core transformations generate bad indexCharOffAddr# call
-------------------------------------+-------------------------------------
        Reporter:  alpmestan         |                Owner:  alpmestan
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:  8.6.1
       Component:  Compiler          |              Version:  8.5
      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:                    |
-------------------------------------+-------------------------------------

Comment (by simonpj):

 A small repro case for the original bug would be super-helpful.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15570#comment:6>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler