[maemo-developers] [maemo-developers] gcc options for smallest size, best speed, etc

[From: David Connolly]

Hi Koen,

On 4/27/06, Koen Kooi <koen at dominion.kabel.utwente.nl> wrote:
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> Øyvind Kolås wrote:
> > On 4/27/06, Philippe Laporte <philippe.laporte at gatespacetelematics.com> wrote:
> >
> >>Hi,
> >>    I would assume that this list be a top source for the following
> >>question: what are the compile options for ARM for gcc for the smallest
> >>possible size, etc.
> >>
> >>For both smallest size, and best speed, seperately of course.
> >>
> >>Or where should I look?
> >
> >
> > One of the changes that have mattered for me is adding -march=armv5te
> > to the CFLAGS.
>
> - -mtune=armv5te should yield the same improvement while retaining
> compatibilty with armv4. Just in case someone tries to build maemo for a
> strongarm platform :)

Actually with arm targets -mtune only accepts values valid for -mcpu
instead of -march.
Unlike x86 where --march implies --mcpu. So armv5te isn't an option
but something like arm920t is.

Does anybody know which of the options supported by -mcpu in gcc 3.3
included with the maemo 1.1 sdk is closest to the ARM926EJ in the
Nokia 770?

I realise gcc 3.4 (used for the kernel build) has support for
-mcpu/-mtune=arm926ej-s, so at least the future is bright :)

> regards,
>
> Koen
>

Regards,

David Connolly