[FFmpeg-devel] [PATCH]Avoid non-strict pointer aliasing in kega decoder

[Reimar Döffinger]

On Mon, Mar 04, 2013 at 08:49:36AM +0000, Carl Eugen Hoyos wrote:
> Reimar Döffinger <Reimar.Doeffinger <at> gmx.de> writes:
> 
> > >With my current patch, the for loop looks like this:
> > >    for (i = inp_off; i < count + inp_off; i++) {
> > >        memcpy(&out[2 * outcnt++], &inp[2 * i], 2);
> > >    }
> > >
> > >When I change that to memcpy:
> > >    memcpy(&out[2 * outcnt], &inp[2 * inp_off], 2 * count);
> > >    outcnt += count;
> > >
> > >I see ugly artefacts.
> > 
> > Maybe inp and out can overlap? Try memmove.
> 
> They often overlap and memmove would change 
> the functionality.
> 
> Is the last patch ok or are there still changes 
> needed?

I don't mind much, but a 2-byte memcpy isn't great.
Also it would be better to figure out why AV_COPY16 isn't working...
Lastly, I think the copy should be made to use memcpy when
it makes sense, something along the lines of the attached
untested patch.
(needs a few *2 to work on top of your patch).
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