Re: BUG in XSHd3 getaddrinfo

[Vincent Lefevre <vincent-opgr@xxxxxxxxxx>]

On 2007-07-27 12:30:36 +0100, Clive D.W. Feather wrote:
> However, the following does *NOT* set p to a null pointer:
> 
>     intptr_t i = (3 + (int) 17.4 - 400 % 38);
>     int *p = (int *) i;

Well, the C standard does not require to set p to a null pointer
(with some loose interpretation, because the C standard uses the
word "conversion" with different meanings), but an implementation
is allowed to set p to a null pointer (but of course, i mustn't
represent a valid pointer), as integer->pointer conversions are
implementation-defined.

> The generated code for a conversion from integer to pointer is *not*
> required to treat 0 specially; it can be a straightforward bit copy.
                   ^^^ non-constant

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Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/>
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