Re: Google SoC Project Proposal: Better Uninitialized Warnings

["Manuel López-Ibáñez" <lopezibanez at gmail dot com>]

On 19/03/07, Diego Novillo <dnovillo@redhat.com> wrote:
> Manuel López-Ibáñez wrote on 03/17/07 14:28:
>
> > This is the project proposal that I am planning to submit to Google
> > Summer of Code 2007. It is based on previous work of Jeffrey Laws,
> > Diego Novillo and others. I hope someone will find it interesting and
>
> Yes, I can act as a mentor.
>
> I'm particularly interested in what we are going to do at -O0.  Ideally,
> I would try to build the SSA form and/or a predicated SSA form and try
> to phrase the problem in terms of propagation of the uninitialized
> attribute.
>
> I agree with your goal of consistency.  The erratic behaviour of the
> current -Wuninitialized implementation is, to me, one of the most
> annoying traits of GCC.  We can't even reorder the pass pipeline without
> running into this problem.

The idea is to have two options -Wuninitialized=precise and
-Wuninitialized=verbose to please both groups of users, those that
want precise warnings about the code that is being compiled in the
current environment  and those that want to get warnings even in the
cases of dead-code or variables removed by optimisers. I think it is
the latter group that is more interested in consistent warnings. Of
course, the former group would welcome consistency as long as it
doesn't imply more false positives.

Nevertheless, I am sure that the final implementation will be very
different from the original proposal but that's life.

From the comments so far, I understand that the project is considered
interesting, so I will formally submit it to Google.

Thanks,

Manuel.