On Thu, Aug 21, 2008 at 11:56 AM, Scott Ribe <[EMAIL PROTECTED]> wrote: >>> Could you tell me which part of the standard states that NULL is 0. > > >> NULL *can* be 0, it isn't *necessarily* 0 > > > It follows from the rules re conversions that it must be either 0, or 0 cast > to a pointer type.
Or an "implementation defined null pointer constant". That is, this is perfectly legal: #define NULL __builtin_special_null_keyword_that_is_specific_to_my_compiler as long as, when __builtin_special_null_keyword_that_is_specific_to_my_compiler is converted to a pointer type, it becomes a null pointer. GCC uses such an implementation defined constant to allow additional warnings when NULL is used in a non-pointer context (i.e. int i = 0;). > No value other than 0 is guaranteed to cast to the > machine's actual null address (whatever bit pattern that might actually be). > > 6.3.2.3 which you quoted, does not provide for any value other than 0. -- Clark S. Cox III [EMAIL PROTECTED] _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to [EMAIL PROTECTED]
