Re: Dereference of undefined pointer value in conftest.c

[Ruben Safir]

On Sun, Dec 06, 2009 at 09:10:47PM +0100, Tomas Carnecky wrote:
> I just ran the clang static analyzer on the xserver configure script and
> it reported a few issues. Most of them were dead assignments/increments,
> but there also was one dereference of an undefined pointer value. I
> don't know which tests the conftest.c belongs to, but I doubt it's to
> test if an application can safely write to unknown memory ;). The test
> contains the following code:
> 
> { /* SCO 3.2v4 cc rejects this. */
>     char *t;
>     char const *s = 0 ? (char *) 0 : (char const *) 0;
>     *t++ = 0; /* <<< t is undefined! */
>     if (s) return 0;
> }
> 
> Tell me if you want more informations or if you are interested in the
> full report from clang.
> 
> tom
> 


This whole piece of code looks screwed up to me.  Why would a trinary
operator try to return anonymous nulls?

Ruben

> 
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