Re: offsetof() macro


There are those who advocate using 0 rather than the NULL macro as a
null pointer constant.  They are, of course, wrong, since they
disagree with me.

(If I were designing the language from scratch, there would be a
keyword, either "nil" or "null", that would be the *only* null pointer
constant.  Using 0 in a pointer context would be a constraint error.

What do you mean by "using 0 in a pointer context"? In another post you have said "An integer constant 0 is a valid null pointer constant. If you assign a null pointer constant to a pointer object, that object's value at execution time will be a null pointer."+"The macro NULL expands to a null pointer constant." And now you say that using 0 is a constraint error. I think I haven't understood yet :-(

And on every compiler I've tried, int *pt=0; works without errors or warnigs. And also the standard says that a constant expression evaluating to 0 or such an expression cast to void*, assigned to a pointer of wathever type makes it a null pointer.

Sorry if I'm wasting your time, but I'm a bit confused...

--
Devaraja (Xdevaraja87^gmail^c0mX)
Linux Registerd User #338167
http://counter.li.org
.

Relevant Pages

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    (comp.lang.c)
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