Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 06 Dec 2007 08:43:42 +0100
From:      Alexander Leidinger <Alexander@Leidinger.net>
To:        Ruslan Ermilov <ru@freebsd.org>
Cc:        Boris Samorodov <bsam@ipt.ru>, Jan Lentfer <Jan.Lentfer@web.de>, freebsd-current@freebsd.org
Subject:   Re: Problems Building 7.0-Beta3 with -Os
Message-ID:  <20071206084342.cv8xbmqg4k0co8kg@webmail.leidinger.net>
In-Reply-To: <20071206072239.GA81748@team.vega.ru>
References:  <4756BAD3.4060905@web.de> <95938867@bb.ipt.ru> <20071205231628.GA15765@dragon.NUXI.org> <20071206072239.GA81748@team.vega.ru>

next in thread | previous in thread | raw e-mail | index | archive | help
Quoting Ruslan Ermilov <ru@freebsd.org> (from Thu, 6 Dec 2007 10:22:39 +0300=
):

> On Wed, Dec 05, 2007 at 03:16:28PM -0800, David O'Brien wrote:
>> [...]  -Os is a collection of
>> optimizations that is between -O1 and -O2.  That is -Os includes
>> everything that -O1 does, and -O2 includes everything that -Os does.
>> In otherwords:  -O1 < -Os < -O2   (properly)
>>
> I read it differently.  From the manpage:
>
> : -Os Optimize for size.  -Os enables all -O2 optimizations that do not
> :     typically increase code size.  It also performs further optimiza-
> :     tions designed to reduce code size.
>
> It says that -Os is a subset of -O2 optimizations plus some
> extra optimizations.  Reading further in a manpage, there's
> only one, -mspace.

And after the import of the new gcc in 7, a lot of people noticed, =20
that the resulting binaries are larger with -Os than with -O2. This =20
doesn't help for the original problem (not being able to compile =20
FreeBSD), but gives a hint to prefer -O2 over -Os when the problem is =20
found.

Bye,
Alexander.

--=20
Is knowledge knowable?  If not, how do we know that?

http://www.Leidinger.net    Alexander @ Leidinger.net: PGP ID =3D B0063FE7
http://www.FreeBSD.org       netchild @ FreeBSD.org  : PGP ID =3D 72077137



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20071206084342.cv8xbmqg4k0co8kg>