Gabriel Dos Reis wrote:
you can (equality) compare a pointer to NULL -- which does not even
happen to designate an object.
Well accurately, you can compare pointers, its not illegal, but the
result of
comparing pointers to separately allocated objects is undefined.
[...]
| One way to think about the semantic model is to consider pointers
| in C to consist of a base/offset pair, where the base points to the
| start of the object (some debugging checkout C compilers even
| use such a format). Then operations on pointers need ONLY
| reference the offset.
that model is too simplistic -- hint: null pointers.
null is a special case indeed, which can be reprsented using a
distinguished offset
-- Gaby
