Re: [Chicken-hackers] Why isn't OPTIMIZE_FOR_SPEED the default?

[Peter Bex]

On Mon, Nov 03, 2014 at 09:38:37AM +0100, Sven Hartrumpf wrote:
> Mon, 3 Nov 2014 09:04:27 +0100, Peter.Bex wrote:
> > How about restoring the optimization option to the defaults and seeing
> > what breaks?  For me it was highly unexpected that CHICKEN was producing
> > completely unoptimized code, and I'm pretty sure I'm not the only one,
> > so if this doesn't break on too many systems, it's a saner default.
> > If it's too aggressive, we could try -O2 instead or even -O1.
> 
> Just my experience with a large application (chicken generates one C file
> of 700 KLOC) and gcc 4.8.N:
> Chicken built
> - with "-O2    -fomit-frame-pointer -march=corei7": has been ok for 2 years 
> or so
> - with "-Ofast -fomit-frame-pointer -march=corei7": caused errors (last 
> checked
>   in late 2013; I can retry if someone is interested)

Cool, that's useful info!  What is -Ofast?  Is it -O3, or something higher?
If retrying isn't too much of a hassle, I'd be interested to know the results
with a recent GCC (and perhaps clang, too).

Using -O2 by default would be a big improvement already, I think.

Cheers,
Peter
-- 
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