[GHC] #7270: Incorrect optimization with Data.ByteString.append

[GHC]

#7270: Incorrect optimization with Data.ByteString.append
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  Reporter:  ocheron                      |          Owner:  igloo           
      Type:  bug                          |         Status:  new             
  Priority:  highest                      |      Milestone:  7.6.2           
 Component:  libraries (other)            |        Version:  7.6.1           
Resolution:                               |       Keywords:                  
        Os:  Unknown/Multiple             |   Architecture:  Unknown/Multiple
   Failure:  Incorrect result at runtime  |     Difficulty:  Unknown         
  Testcase:                               |      Blockedby:                  
  Blocking:                               |        Related:                  
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Comment(by ocheron):

 Thank you, my initial problem (with the package tls-0.9.10) is solved with
 this patch applied on top of bytestring-0.10.0.0.
 Though I had to fix imports in Data/ByteString.hs: unsafeDupablePerformIO
 seems to be missing.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7270#comment:7>
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