Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 7 May 2004 13:08:32 -0700 (PDT)
From:      Doug White <dwhite@gumbysoft.com>
To:        David O'Brien <obrien@freebsd.org>
Cc:        current@freebsd.org
Subject:   Re: src/sys/vm/vm_init.c v1.43 hangs amd64
Message-ID:  <20040507130607.Q42861@carver.gumbysoft.com>
In-Reply-To: <20040505054723.GB30514@dragon.nuxi.com>
References:  <20040430135155.C67990@carver.gumbysoft.com> <20040505054723.GB30514@dragon.nuxi.com>

next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, 4 May 2004, David O'Brien wrote:

> On Sat, May 01, 2004 at 08:42:46AM -0700, Doug White wrote:
> > 2.  Changing COPTFLAGS to '-O -frename-registers -pipe' from the default
> > '-O2 -frename-registers -pipe' stops the crash. So it may be an
> > O2-specific optimization bug.
> ...
> > So in the end, at -O2, (nswbuf*MAXPHYS) != nswbuf*MAXPHYS. Creepy, eh?
> > I'll see if I can come up with a standalone test case to submit to the gcc
> > folks.
>
> Thanks!
> This is the first report of an -O2 problem, and I'm very happy you're
> willing to try to narrow this down so we don't have to return to -O[1].

I caught kan's attention with this last night on irc, and he's going to
try to isolate the bad code generation. We could really use a standalone
case to test with & submit, but a naieve test doesn't come up with any
differences.

In order to keep my amd64 stable I'm having to leave COPTFLAGS set, so if
someone commits a fix to gcc or imports a new version, try to get my
attention so I can test it with -O2 again.

Also if we get into the 5.3 release timeframe we'll have to make a call to
ship with a -O2 compiled kernel or not.

-- 
Doug White                    |  FreeBSD: The Power to Serve
dwhite@gumbysoft.com          |  www.FreeBSD.org



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20040507130607.Q42861>