Thread-Safety

QPromise is thread-safe and can be copied and accessed across different threads. QPromise relies on explicitly data sharing (opens new window) and thus auto p2 = p1 represents the same promise: when p1 resolves, handlers registered on p1 and p2 are called, the fulfilled value being shared between both instances.

IMPORTANT

While it's safe to access the resolved value from different threads using then, QPromise provides no guarantee about the object being pointed to. Thread-safety and reentrancy rules for that object still apply.