Re: compiler warning with VS 2017

On 05/05/17 06:50, Tom Lane wrote:
> Haribabu Kommi <kommi(dot)haribabu(at)gmail(dot)com> writes:
>> I am getting a compiler warning when I build the latest HEAD PostgreSQL with
>> visual studio 2017.
>> The code at the line is,
>> tuple->values[i] = (char *) (Size)0xdeadbeef; /* make bad usage more obvious */
>
> Yeah, you're not the first to complain about this. To my mind that
> coding is not pretty, not cute, and not portable: there's not even
> a good reason to believe that dereferencing the pointer would result
> in a crash. Perhaps the author can explain to us why this is better
> than just assigning NULL.
>
> Actually, looking around a bit there, it's not even clear why
> we should be booby-trapping the value of an unchanged column in
> the first place. So I'd say that not only is the code dubious
> but the comment is inadequate too.

Hmm, as far as I can recollect this is just leftover debugging code that
was intended to help ensure that we are checking the "changed"
everywhere we are supposed to (since I changed handling of these
structured quite a bit during development). Should be changed to NULL,
that's what we usually do in this type of situation.

--
Petr Jelinek http://www.2ndQuadrant.com/
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