GCancellable behavior and return timing for async operations

Vala leverages the GLib event loop to manage asynchronous operations through async and await keywords. To handle operation termination, GCancellable objects are passed to these functions to signal that a process should stop.

Because Vala transforms await into GTask callbacks in the underlying C code, the actual point at which control returns to the caller after a cancellation signal is sent depends on the implementation's frequency of checking the cancellable state.

There is uncertainty regarding the guarantee of execution flow when a GCancellable is triggered during a long-running asynchronous task.

• What is the guaranteed behavior for the return of an await expression immediately after GCancellable.cancel() is invoked?
• Does the Vala runtime provide a mechanism to force an immediate return to the awaiter, or is it strictly dependent on the underlying GLib implementation's polling of the cancellation state?