Re: ICC Profile

Branko Badrljica wrote:
> BTW: Is ICC really worth the fuss ?
> I have checked around and reported that newest gcc-4.3 is able to to 
> catch and sometimes even outperform icc ( not always, naturally).
> 
> Big news seemed to be thatnew gcc si close and sometimes better than icc.
> 
> Is it any truth to that and if it is, what is the motive of having 
> non-open icc option ?

The programs where I care about speed the most are gzip, bzip2, oggenc, 
lame, x264...  I guess you get the "pattern", they're 
encoders/compressors.  ICC wins in every one of them (speed increase is 
quite dramatic in the case of gzip and bzip2; 20% to 30%).  GCC won with 
diffutils though; 2% faster than ICC.

Testing other tools is difficult; how do you measure if X is faster with 
ICC?  Or KDE?  (If it even compiles with ICC; didnt' test.)

There's the issue of bugs though; programs break even with different 
versions of GCC (see Thunderbird; it breaks when compiled with *any* 
form of optimization turned on with GCC 4.3. See bugs 223375 and 
217805).  Who knows what breakage can occur with ICC.  The vast majority 
of projects out there are developed and tested only on GCC systems.

Then there's the show stopper #1 bug: every C++ source file that has an 
#include <limits.h> refuses to compile with ICC (at least on my system; 
AMD64).  Intel responds with "use RedHat where it works, we don't 
support Gentoo."  Supporting ICC in Gentoo is probably going to be too 
difficult if Intel refuses to even try to fix bugs that don't show up in 
RedHad and Novell's "enterprise" SUSE.

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