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

[GHC]

#15570: Core transformations generate bad indexCharOffAddr# call
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        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:                    |
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Changes (by alpmestan):

 * owner:  (none) => alpmestan
 * milestone:   => 8.6.1


Comment:

 I'm going to try and characterise where both builds differ, using
 `-dverbose-core2core`. The best theory at this point is that libraries are
 built with different enough options that this affects the optimisation
 pipeline on this example. This won't be the end of the story though, as we
 simply ''never'' want to end up with the Core for `f` mentionned above.
 But at that point we will also have a lot more information about how the
 Core evolves.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15570#comment:1>
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