Re: Should -Wmaybe-uninitialized be included in -Wall?

[Jeff Law <law at redhat dot com>]

On 07/09/2013 07:56 AM, Andreas Arnez wrote:
> Andrew Haley <aph@redhat.com> writes:
>
> > On 07/09/2013 12:59 PM, Andreas Arnez wrote:
> > > With this situation at hand, I wonder whether it's a good idea to keep
> > > maybe-uninitialized included in -Wall.  Projects which have been using
> > > "-Wall -Werror" successfully for many years are now forced to
> > > investigate non-existing bugs in their code.
> >
> > But maybe-uninitialized is very useful, and it's not really inappropriate
> > for -Wall.
>
> The warning would be extremely useful, if false positives didn't obscure
> real problems.  In its current state I consider its usefulness limited.
Depends on your point of view.  This topic has been hashed through 
repeatedly on this list.

I personally like -Wall -Werror.  While we do run into false positives 
and the set of false positives does change from release to release as a 
result of optimizations, I believe there's been an overall improvement 
in the quality of the codebases that use -Wall -Werror.  I certainly see 
fewer bugs these days blamed on the compiler which are in fact 
uninitialized variables.


I'd like to revamp how we do path isolation to eliminate more of the 
false positives, but this warning is by its nature going to generate 
false positives.

What I would ask is that folks continue to file bugs for false 
positives.  While I can't guarantee we'll fix them, they do provide a 
good base of tests for path sensitive analysis.


I'd also suggest that when an initialization is added merely to avoid 
the warning that a comment be added to the code so that folks know it's 
merely to avoid the warning.


Jeff