Re: Announce: gcc bogus warning repository

Andrew Morton
2006-10-01T18:12:41Z

On Sun, 01 Oct 2006 08:40:13 -0700
Daniel Walker <dwalker@mvista.com> wrote:

> On Sun, 2006-10-01 at 09:44 -0400, Jeff Garzik wrote:
> > The level of warnings in a kernel build has lately increased to the
> > point where it is hiding bugs and otherwise making life difficult.
> >
> > In particular, recent gcc versions throw warnings when it thinks a
> > variable "MAY be used uninitialized", which is not terribly helpful due
> > to the fact that most of these warnings are bogus.
> >
> > For those that may find this valuable, I have started a git repo that
> > silences these bogus warnings, after careful auditing of code paths to
> > ensure that the warning truly is bogus.
> >
> > The results may be found in the "gccbug" branch of
> > git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/misc-2.6.git
> >

Funny - I started doing the exact same thing here just eight hours ago.
I'll send you anything which isn't in that git tree, thanks.

> Steven Rostedt an I worked on this problem in May. Steven came up with,
> a nice way to handle these warnings, which doesn't increase code size.
> Here's the post if your interested.
>
> http://lkml.org/lkml/2006/5/11/50

I think we should merge that and use it. No overhead, self-documenting,
easily greppable for.

The downsides are that it muckies up the source a little and introduces a
very small risk that real use-uninitialised bugs will be hidden. But I
believe the benefit outweighs those disadvantages.