Neil Conway <[EMAIL PROTECTED]> writes:
> Ah, good catch! Upon further investigation, you're completely correct:
> technically, you need to cast the NULL literal to a pointer type in a
> function call if (a) there is no prototype for the function, or (b)
> the function is a varargs function (which execl() is).

> I'd imagine it would only make a difference on a machine where the
> null pointer is represented by a non-zero bit pattern (i.e. it
> shouldn't make a difference on any modern machine),

Actually, I think it would be likely to be important on any machine
where sizeof(pointer) != sizeof(int), which is reasonably common
in 64-bit-pointer land.  C99 saith

       An integer constant expression with  the  value  0,  or
       such  an  expression  cast  to type void *, is called a null
       pointer constant.

So one plausible definition of NULL is just "#define NULL 0", and
without the explicit cast it would probably be taken as an integer
argument, which would be the wrong size.

> but we should do this correctly, of course.


> I won't bother posting an updated patch, but I'll include your fix in
> the patch when I apply it. Thanks again.

Sounds good.

                        regards, tom lane

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