clang vs gcc build performance (executable not build time)

Caolán McNamara caolanm at
Tue Nov 23 16:27:54 UTC 2021

On Tue, 2021-11-23 at 17:11 +0100, Luboš Luňák wrote:
> > 
>  We don't use -Os, at least my local optimized build doesn't. A bunch
> of solenv/gbuild/platform files do set it, but it doesn't get selected
> here.

>  And according to logs those -Os come from at least 10 years ago, so if
> the idea is to use them, maybe it would be a good idea to re-check the
> effect they have.

We've used -O2 for x86_64 since:

"2006/03/06 11:47:01 kendy #i62814#
x86-64: -O2 instead of -Os for the optimized builds"

x86 was -Os back then, and still is. The rest of the platforms using
-Os are probably just cnp or a general vague feeling that -Os is a good
choice for limited hardware.

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