Re: "Experimental" features in releases

[Dale Johannesen <dalej at apple dot com>]

On Apr 19, 2006, at 12:04 AM, Kai Henningsen wrote:
> dberlin@dberlin.org (Daniel Berlin)  wrote on 18.04.06 in  
> <1145340618.28433.36.camel@dberlin.org>:
>
> > This is in fact, not terribly surprising, since the algorithm used  
> > was the
> > result of Sebastian and I sitting at my whiteboard for 30 minutes  
> > trying to
> > figure out what we'd need to do to make swim happy :).
>
> > This would leave -ftree-loop-linear in 4.2, but make it not useful  
> > for
> > increasing SPEC scores.
>
> So is this an object lesson for why optimizing for benchmarks is a bad
> idea?

If you're inclined to believe this, you could find a confirming  
instance here, but there are other lessons that could be drawn.  If  
you go back to the original thread, you'll see this from Toon Moene:
http://gcc.gnu.org/ml/gcc-patches/2004-09/msg00256.html
It didn't have to be a benchmark-only optimization.