Wireshark mailing list archives
Re: About Dead Store in clang Analysis
From: John Sullivan <jsethdev () kanargh force9 co uk>
Date: Thu, 24 Mar 2011 22:59:20 +0000
On Thursday, March 24, 2011, 8:57:42 PM, Chris Maynard wrote:
Alexis La Goutte <alexis.lagoutte@...> writes:
What it the official solution to fix this ? 1) Remove the code 2) Ignore this warning 3) Comment the code add a /* offset += 1; Remove Clang Dead increment */
Or ... convert the dissector to a "new-style" dissector where the number of bytes it consumes is returned, and in that case the offset should be incremented but will need to be returned from any functions so proper offset (and thus the proper number of bytes consumed) can be maintained and eventually returned from the dissector.
In fact it sort of does, except that it returns the calculated number of bytes from the tag header. It might be then useful to compare this value calculated from the header, with the actual number of bytes dissected. Rather than just assume they will end up the same and throw one away. We could be over- or under- dissecting, or the end point could be passing garbage, and figuring that out is a main use case! (Aside: my attitude to dead stores is that eliminating them is a job for the compiler. The programmer's job is not to micro-optimize things that can be done better by machine, but to structure the code so as to make the semantics as clear as possible. And I think that includes, as already pointed out, leaving things in a clean state for when the next field is added to the end of that tag.) John -- Dead stars still burn ___________________________________________________________________________ Sent via: Wireshark-dev mailing list <wireshark-dev () wireshark org> Archives: http://www.wireshark.org/lists/wireshark-dev Unsubscribe: https://wireshark.org/mailman/options/wireshark-dev mailto:wireshark-dev-request () wireshark org?subject=unsubscribe
Current thread:
- About Dead Store in clang Analysis Alexis La Goutte (Mar 24)
- Re: About Dead Store in clang Analysis Stephen Fisher (Mar 24)
- Re: About Dead Store in clang Analysis Dirk Jagdmann (Mar 24)
- Re: About Dead Store in clang Analysis Chris Maynard (Mar 24)
- Re: About Dead Store in clang Analysis Jeff Morriss (Mar 24)
- Re: About Dead Store in clang Analysis John Sullivan (Mar 24)
- Re: About Dead Store in clang Analysis Dirk Jagdmann (Mar 24)
- Re: About Dead Store in clang Analysis Guy Harris (Mar 24)
- Re: About Dead Store in clang Analysis Guy Harris (Mar 24)