[GHC] #12757: Compiled program segfaults at -O1

[GHC]

#12757: Compiled program segfaults at -O1
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        Reporter:  hvr               |                Owner:
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:  8.0.2
       Component:  Compiler          |              Version:  8.1
      Resolution:                    |             Keywords:
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  Runtime crash     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #11312, #12585    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by bgamari):

 Siarheit had some insight on this. The problem here is essentially that
 `bytestring` traverses a `ByteString` by walking until `currPtr == (
 "literal"# +# length "literal"# )` where `currPtr` is initialized with
 `"literal"#`. This means that if `"literal"#` is inlined twice, you will
 end up with `currPtr` and `"literal"# +# length "literal"#` pointing into
 two separate chunks of memory, with who-knows-what in between.

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/12757#comment:6>
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