3 ms·
An empty loop that has no computation but loops forever has an observable side-effect.
by scott_s 13y ago
An empty loop that has no computation but loops forever has an observable side-effect.
- nhaehnle 13y agoGo read page 14 of this: http://isocpp.org/files/papers/N3690.pdf http://isocpp.org/files/papers/N3690.pdf ;-) Essentially, C++ does not consider looping forever to be a side effect. You have to do something like writing to a volatile variable to ensure that the compiler does what you want.
- gizmo686 13y agoThe relevent part of page 14: "The implementation may assume that any thread will eventually do one of the following: — terminate, — make a call to a library I/O function, — access or modify a volatile object, or — perform a synchronization operation or an atomic operation. [ Note: This is intended to allow compiler transformations such as removal of empty loops, even when termination cannot be proven. — end note ]"