Re: memset all bits to zero will let float/double to zero?

From: Richard Bos (rlb_at_hoekstra-uitgeverij.nl)
Date: 06/28/04 

Date: Mon, 28 Jun 2004 06:11:55 GMT

"Malcolm" <malcolm@55bank.freeserve.co.uk> wrote:

> "Keith Thompson" <kst-u@mib.org> wrote in message
> >
> > For most implementations, null pointers are represented as all-
> > bits-zero, even though using a different representation would
> > only break invalid code. Perhaps that's just inertia.
> >
> I think the main reason is psychological. foo(0) passes a NULL pointer to
> foo(), so an implementor is going to use all bits zero as the representation
> unless there is a really pressing reason to do otherwise.

Huh? Non sequitur, methinks.

> Then there's the
> problem of code that uses memset() or calloc() to intialise pointer data.

The problem is in that code, not in the non-zero representation of a
null pointer where this is useful.

Richard

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