Alexander Terekhov wrote:
Peter Dimov wrote:
Alexander Terekhov wrote:
Peter Dimov wrote:
Alexander Terekhov wrote:
No, it's not; C++ behavior _is defined in terms of_ volatile (and I/O calls), not the other way around.
As if rule. And C++ says nothing about mutiple threads.
Nope. "As if" is defined in terms of observable behavior, and "observable behavior" is defined in terms of volatile and I/O.
int main() { volatile int a = 1; return --a; }
prove that it can't be transformed to
int main() { }
The observable behavior is
write volatile @a 1
nop
read volatile @a x
nop
write volatile @a x-1
nop
exit(x-1)
push 0 call _exit
in the first case, and
Happy now (debugger notwithstanding)?
No. A conforming compiler is not allowed to do that.
C'mon, volatile is brain-dead.
Nobody's arguing otherwise. ;-) But a nop it isn't.