Karen Shaeffer <[EMAIL PROTECTED]> writes: > I see your point. My sticking point is that the process is actually > running on a physical machine. And the addresses, although virtual, > do translate to a unique physical memory location. And, the value > stored in that location cannot be 0 and 5 at the same time. And my > comments were addressing that the undefined behavior of this illegal > assignment should not violate the physical constraints of what is > actually stored in that physical address. I would be OK with -1 > being stored in there, or zero, or whatever, or the process crashing, > but what I see is not congruent with my thinking about the limits > of the compiled binary at run-time. Obviously I need to rethink those > assumptions.
Undefined behaviour is undefined behaviour. You can not predict what the compiler do. > the value > stored in that location cannot be 0 and 5 at the same time. No, but in the presence of undefined behaviour the compiler is perfectly free to assume that that is in fact the case. This isn't intentional, of course; it just falls out of other optimizations. Ian
