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Re: speed problem with several g++ versions


"Andreas Kowarz" <kowarz@math.tu-dresden.de> wrote in message 410E3788.1080806@math.tu-dresden.de">news:410E3788.1080806@math.tu-dresden.de...
>
> Hello,
>
> we made some interesting experience while implementing and testing a software
> package, which makes use of overloaded operators. One aspect of the
> implementation is the speed of the resulting binaries. To find the best solution
> we have tested the following approaches: normal overloading and templates. The
> example (attachment) contains the source code for 3 programms:
>
> prog     - execution without overloading
> progtemp - template based
> progover - normal overloading
>
> Compiled with g++ version 3.2 we got the following runtime:
> prog       about 2.9 seconds
> progtemp   about 2.9 seconds
> progover   about 3.5 seconds
> It seems clear that the template based implementation should be the one to use.
>
> After recompiling with g++ version 3.4.1 we got a complete different result:
> prog       about 2.9 seconds
> progtemp   about 15.4 seconds !!!
> progover   about 3.5 seconds
> This time the template version is not really good. :-(
> (Same problem with g++ version 3.3.2 on a different machine)
>
> My questions are:
> - Is this a known problem?
> - Is there a compiler switch which can solve the problem?
>
> Sincerely yours,
>
> Andreas Kowarz
>

tar (GNU tar) 1.13.25  doesn't extract files from example.tar which contains tested sources.



-- 
   Alex Vinokur
     http://mathforum.org/library/view/10978.html
     http://sourceforge.net/users/alexvn





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