[GHC] #14361: GHC HEAD miscompiles `text-containers`

[GHC]

#14361: GHC HEAD miscompiles `text-containers`
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        Reporter:  hvr               |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:  8.4.1
       Component:  Compiler          |              Version:  8.3
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 Some facts:
 * Allocating all `ByteArray#`s as pinned makes no difference.
 * Marking `TextArray.Unboxed.indexOfsLen'` as `NOINLINE` makes the problem
 vanish
 * Removing the `assert`s in `lookupIndexNear` makes no difference

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14361#comment:8>
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