Re: CONFIG_TINY

Bill Davidsen
2002-11-01T02:04:10Z

On Thu, 31 Oct 2002, Tom Rini wrote:

> On Thu, Oct 31, 2002 at 12:12:40PM -0500, Mark Mielke wrote:
>
> > On Thu, Oct 31, 2002 at 10:04:20AM -0700, Tom Rini wrote:
> > > On Thu, Oct 31, 2002 at 11:51:13AM -0500, Mark Mielke wrote:
> > > > Or specified more clearly: If the compiler optimization flag is
> > > > configurable, choosing CONFIG_TINY should default the optimization flag
> > > > to -Os before it defaults the optimization flag to -O2.
> > > You're still missing the point of flexibility remark. Changing the
> > > optimization level has nothing to do with CONFIG_TINY, and is a
> > > generally useful option, and should be done seperate from CONFIG_TINY.
> > > In fact people seem to be getting the wrong idea about CONFIG_TINY. We
> > > ...
> >
> > Please read it again... even if the optimization flag was
> > configurable, choosing CONFIG_TINY should *default* the optimization
> > flag to -Os before it defaults the optimization flag to -O2.
>
> Yes, and I'm saying that CONFIG_TINY shouldn't exist. It should be
> CONFIG_FINE_TUNE (or so), to allow anyone to fine tune the optimization
> level. Changing optimization levels is a speed / size tradeoff (if it
> wasn't, there wouldn't be -O2 / -Os, they would do the same thing) which
> you cannot pick a sane default for.

By that reasoning there shouldn't be -O2 either, everyone should be forced
to diddle everything for their architecture, cache size, gcc revision,
patch level... does that sound as unrealistic to you as it does to me? -Os
is a default, just like -O2, and if you want small -Os is probably a
better starting point.

As noted in another note, anyone good enough to make those decisions is
probably able to find a string in a Makefile.

--
bill davidsen <davidsen@tmr.com>
CTO, TMR Associates, Inc
Doing interesting things with little computers since 1979.