optimization levels for 6-STABLE build{kernel,world}

Oliver Fromme olli at lurza.secnetix.de
Wed Sep 13 02:26:07 PDT 2006

Stefan Lambrev wrote:
 > Oliver Fromme wrote:
 > > The default CFLAGS are "-O2 -pipe -fno-strict-aliasing".
 > > Anything above -O2 isn't supported, and using -O2 without
 > > -fno-strict-aliasing also isn't supported (and will create
 > > broken code for some programs).  A common mistake is to
 > > specify CFLAGS="-O2 -pipe" and omit -fno-strict-aliasing.
 > > That'll shot you in the foot sooner or later.
 > May be default flags have to be set here:
 > /usr/src/share/examples/etc/make.conf ?
 > I'm asking because in this file I read:
 > # CFLAGS controls the compiler settings used when compiling C code.
 > # Note that optimization settings other than -O and -O2 are not recommended
 > # or supported for compiling the world or the kernel - please revert any
 > # nonstandard optimization settings to "-O" or -O2 before submitting bug
 > # reports without patches to the developers.
 > #
 > #CFLAGS= -O -pipe
 > May be "-fno-strict-aliasing" have to be added here then ?

Yes, you are right.  I think a clarification should
be added to the make.conf(5) manual page and to the
/usr/share/examples/etc/make.conf file.

Someone care to submit a PR ...?

Best regards

Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
Dienstleistungen mit Schwerpunkt FreeBSD: http://www.secnetix.de/bsd
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