Re: using literal zero for NULL

On Tue, 21 Mar 2006, mikecorn wrote:

> I just tried rebuilding my GTK apps for a 64 bit Linux system (Fedora core
> 5), and had an ugly surprise: random segmentation faults. I traced at least
> one of them to my lazy habit of using a literal zero in place of NULL for an
> optional function argument or end-of-arg-list indicator. I speculate that
> the compiler is supplying a 32 bit zero where a 64 bit zero is needed.
> Correct? If so, it seems this is a compiler bug, since the type conversion
> should be automatic. Can someone confirm this?

There's no way for the compiler to know that the sentinel is
supposed to be a pointer.  It's simply implemented as a varargs
function.  Maybe we should emphasize the importance of using NULL
in our documentation.


"Commandment Three says Do Not Kill, Amendment Two says Blood Will Spill"
	-- Dan Bern, "New American Language"

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