Re: Let's use gcc-4.2, not 4.1 -- OpenMP

From: David O'Brien <obrien_at_freebsd.org>
Date: Fri, 15 Dec 2006 12:43:01 -0800
On Thu, Dec 14, 2006 at 08:44:53PM -0800, Steve Kargl wrote:
> On Fri, Dec 15, 2006 at 02:50:30PM +1030, Daniel O'Connor wrote:
> > On Friday 15 December 2006 05:50, Scott Long wrote:
> > > Yes, the industry moves fast, but that's no reason to fool ourselves
> > > into thinking that the FSF will support GCC 4.2 a day after they release
> > > 4.3 and start working on 4.4.  Your point above about the lifespan of
> > > FreeBSD 7.x is a valid one, and I agree that it should be a
> > > consideration.  Vendor support is a myth and should not be a
> > > consideration.
> > 
> > Not to mention it is *trivial* to install a compiler using ports or packages.
> > 
> > If you are serious about high performance computing installing a new compiler 
> > is about the lowest barrier you'll find.
> > 
> 
> Actually, 4.1.x will produce much worse code than 3.4.6.
> You can search the gcc mail listings for extensive comparison
> by Clinton Whaley (the author of math/atlas) for details.

It depends on the type of code and benchmark.  Clinton's code is mostly
FP.  I've seen other benchmarks that show an improvment with 4.1.x over
3.4.6 and 4.2 does even better.
 
-- 
-- David  (obrien_at_FreeBSD.org)
Received on Fri Dec 15 2006 - 19:43:03 UTC

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