Subject: Re: DRI [was: Re: more summer of code fun]
To: None <tech-kern@NetBSD.org, tech-x11@NetBSD.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-x11
Date: 06/24/2005 20:22:27
> Well, I know this patent, and it's about the comparison of two
> pointers with the aim of finding out whether they actually point to
> the same memory.  I think we're doing this pretty often.

Probably.

> Think e.g. NULL pointer checks after malloc calls here.

That's not an instance.  NULL does not point to any memory, so it
doesn't make sense for comparison against it to be comparing two
pointers to find out whether they point to the same memory; it's
comparing two pointers to find out whether one of them fails to point
to memory at all (since the other one is known to not point to memory).

Of course, depending on exactly how the patent is worded, that
difference may not matter.

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