This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug c/36359] [Regression] compile error in linux-kernel 2.6.26-rc4 with -O2
- From: "pinskia at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 8 Jun 2008 00:33:49 -0000
- Subject: [Bug c/36359] [Regression] compile error in linux-kernel 2.6.26-rc4 with -O2
- References: <bug-36359-16254@http.gcc.gnu.org/bugzilla/>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Comment #9 from pinskia at gmail dot com 2008-06-08 00:33 -------
Subject: Re: [Regression] compile error in linux-kernel 2.6.26-rc4 with -O2
On Sat, Jun 7, 2008 at 5:17 PM, mt-ml at gmx dot de
<gcc-bugzilla@gcc.gnu.org> wrote:
> As you can see, the argument to ilog2 is urb->interval which can't be zero at
> that point IMHO.
Yes and that requires a lot of jump threading and many other
optimizations to detect that really. First PRE has to be working and
then VRP has to figure out it will be greater than 0. So really this
code depends on optimization to work correctly and the kernel is
broken that way again (not suppressing really)
-- Pinski
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36359