* data read before the pointer read by speculating the value of the pointer.
* Correct ordering is ensured because the pointer is read as a volatile access.
* This acts as a global side-effect operation, which forbids reordering of
* data read before the pointer read by speculating the value of the pointer.
* Correct ordering is ensured because the pointer is read as a volatile access.
* This acts as a global side-effect operation, which forbids reordering of