Subject: Re: CFLAGS and lfs
To: Martin Husemann <firstname.lastname@example.org>
From: Todd Vierling <email@example.com>
Date: 10/15/2000 20:33:36
On Sat, 14 Oct 2000, Martin Husemann wrote:
: > Anyone know where in the source tree to set optimization flags for the
: > c compiler? I would like to try and make the world with -06 if possible.
: You can change /usr/share/mk/sys.mk or set /etc/mk.conf.
: But beware: I used to build the world on i386 with -O6 for some time (just
: to test this) and found at least two gotchas: the bootblocks won't work
: and there were optimization errors in the softdep code, leading to random
: crashes under heavy file system load. Going back to -O2 imediately fixed
There are some optimization errors at levels above -O2 in the in-tree egcs
1.1.2 that make using above -O2 a risky operation (as is documented in the
gcc docs). If you want a smidgin faster binaries, use optimization flags
that reflect your target CPU: -mpentiumpro or -m486 with -O2.
Note that -O is equivalent to -O3 in the egcs 1.1.x that is in-tree.
I don't know offhand whether gcc 2.95.2, which I'm working to switch to in
-current, has differences between -O.
-- Todd Vierling <firstname.lastname@example.org> * http://www.wasabisystems.com/
-- Speed, stability, security, and support. Wasabi NetBSD: Run with it.