[tor-bugs] #31025 [Core Tor/Tor]: Coverity is confused by switch statement in siphash24 implementation

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#31025: Coverity is confused by switch statement in siphash24 implementation
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 Reporter:  nickm         |          Owner:  nickm
     Type:  defect        |         Status:  needs_review
 Priority:  Medium        |      Milestone:  Tor: 0.4.2.x-final
Component:  Core Tor/Tor  |        Version:
 Severity:  Normal        |     Resolution:
 Keywords:  coverity      |  Actual Points:  .1
Parent ID:                |         Points:
 Reviewer:                |        Sponsor:
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Changes (by nickm):

 * status:  assigned => needs_review
 * actualpoints:   => .1


Comment:

 https://github.com/torproject/tor/pull/1153 (`ticket31025`) is the best I
 could come up with here: using a slightly different byte-copy
 implementation when building for coverity.

 I tried switching to this implementation unconditionally, but it caused a
 performance regression in siphash.

 I do not know for certain if this will shut coverity up or not. :)

 Another alternative might be writing a coverity model for the siphash24
 function.  I don't actually know how to do that correctly, though.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/31025#comment:1>
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