[SDL] Problem with reusing array of surfaces.

[David Olofson]

On Friday 09 May 2003 16.43, David Olofson wrote:
> On Friday 09 May 2003 16.05, Sweeney, Steven (FNB) wrote:
> [...]
>
> > 3. Calling,
> >
> > if (image[0] == NULL)
> >
> > and image[0] was never set to NULL to begin with will / might
> > cause seg faults.
>
> Have you actually seen this happen on anything like a PC or
> workstation CPU? It takes a rather weird architecture to segfault
> by just checking the value of a pointer... The problem is that the
> NULL test thinks any garbage is a valid pointer.

Of course, that's probably exactly what you meant... :-)


> Either way, I'd write (NULL == image[0]) instead, just in case '=='
> accidentally becomes '='. I think you can also assume that NULL ==
> 0 on any architecture currently in use, so you can just do
> if(image[0]) ...; to avoid that problem entirely.

...and "if(NULL == image[0])" would become "if(!image[0])", obviously.


I should probably not try to do anything important until my fever gets 
a bit better. Can't think straight. (Well, I mean, it's harder than 
usual. ;-)


//David Olofson - Programmer, Composer, Open Source Advocate

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