Re: -Wuninitialized issues

[Chris Lattner <sabre at nondot dot org>]

Bernhard R. Link wrote:
> * Chris Lattner <sabre@nondot.org> [051102 19:28]:
> > Jeff Law wrote:
> > >> I prefer consistency in warnings, regardless of optimization level.
> > >I disagree and I think we have a significant contingency of
> > >users that would disagree

> > Jeff, I completely agree with you for some class of users (users being
> > developers who use GCC but don't hack on GCC itself).
> >
> > OTOH, there is also a very large class of users (like myself) who have
> > to write code that works well across several different compilers.

> Why do you have to do something about a warning that is a clear false
> positive?
..
> I'd much prefer a warning about a "may be used uninitialized"
> on less clever compiler over the change to lose a "is used unitialized"
> warning some future more clever compiler may find

You clearly fall into the "class of users" I mentioned above, that like 
*potentially* more precise warnings at any cost.

To me, I would rather have that obvious false-positive case warned about. 
It will certainly be warned about on other (non-GCC) compilers, so the 
variable will have to be explicitly initialized in my code whether GCC 
warns about it or not.

If you compile your code with *one specific version* of GCC and use no 
other compilers, I agree that accurate data-flow-based warnings are quite 
useful (particularly if/when all of the cases where data-flow-based 
warnings generating *more* false positives are fixed).

All I'm saying is that I do not fall into that catagory, so I don't find 
them useful.  I also posit that I'm not the only one writing portable 
code, and using GCC as a compiler to do so.  Given this, I'm just saying 
that having some way to get "front-end" style warnings would be useful. :)

-Chris

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