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  1. JDK
  2. JDK-8221120

CopyOnWriteArrayList.set should always have volatile write semantics

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        A user noticed that CopyOnWriteArrayList.set no longer does a volatile write when the new element is already present in its slot.

        https://concurrency.markmail.org/thread/sdx7ehxrjqzrqmiy

        Although such usage is questionable, and one can argue there is no guarantee of happens-before when the element is not in need of an update, and in practice no one will ever notice since the JVM is unlikely to optimize away the synchronized block in the method's implementation, nevertheless we should revert to an unconditional volatile write as seen in jdk8.

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            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8226667 CopyOnWriteArrayList.set should always have volatile write semantics

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved

            Backport - A issue that is required to port a Bug or Feature into another product release. This issue type is generally associated with the main Bug/Feature to represent each individual release of the port. JDK-8235319 CopyOnWriteArrayList.set should always have volatile write semantics

            • P4 - Minor loss of function, or other problem where easy workaround is present.
            • Resolved
            relates to

            Enhancement - null JDK-8200258 Improve CopyOnWriteArrayList subList code

            • P3 - Major loss of function.
            • Resolved

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                martin Martin Buchholz
                martin Martin Buchholz
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