Required Instance Methodswift 6.0.3_Concurrency

    checkIsolated

    Last resort “fallback” isolation check, called when the concurrency runtime is comparing executors e.g. during assumeIsolated() and is unable to prove serial equivalence between the expected (this object), and the current executor.

    iOS
    18.0+
    macOS
    15.0+
    tvOS
    18.0+
    visionOS
    2.0+
    watchOS
    11.0+
    func checkIsolated()
    Mangled symbol
    sScf13checkIsolatedyyF What are these?
    FNV24 hash
    5C5MY

    During executor comparison, the Swift concurrency runtime attempts to compare current and expected executors in a few ways (including “complex” equality between executors (see isSameExclusiveExecutionContext(other:)), and if all those checks fail, this method is invoked on the expected executor.

    This method MUST crash if it is unable to prove that the current execution context belongs to this executor. At this point usual executor comparison would have already failed, though the executor may have some external tracking of threads it owns, and may be able to prove isolation nevertheless.

    A default implementation is provided that unconditionally crashes the program, and prevents calling code from proceeding with potentially not thread-safe execution.