[tor-bugs] #15901 [Tor]: apparent memory corruption -- very difficult to isolate

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#15901: apparent memory corruption -- very difficult to isolate
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     Reporter:  starlight  |      Owner:
         Type:  defect     |     Status:  new
     Priority:  critical   |  Milestone:  Tor: 0.2.7.x-final
    Component:  Tor        |    Version:  Tor: 0.2.6.10
   Resolution:             |   Keywords:
Actual Points:             |  Parent ID:
       Points:             |
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Comment (by starlight):

 I allow that the problem is deterministic and once
 the bad state sets in, results in consistent
 corruption of the zlib inflate of successive
 copies of the document either as part of the
 operation or immediately after.  But reject that
 gcc is generating bad code for zlib either
 LTO or non-LTO.  This is gcc 4.9.3.  I have
 not seen a material GCC bug in ten years.
 Every single time since the mid-2000s I thought
 I had a compiler bug it turned out to be
 something else.  That a GCC code generation
 bug would affect zlib 1.2.8 is beyond
 improbable.

 Possibly some corruption in memory is leading
 to consistently repeated bad zlib inflates.
 Is strangest problem I've come across
 --ever I think.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/15901#comment:30>
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