16f6c0aecf
Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in.
72 lines
1.4 KiB
Plaintext
72 lines
1.4 KiB
Plaintext
== Why is this an issue?
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Primitives can be read and written to atomically. Except for ``++long++`` and ``++double++``, that is. These 64-bit primitives must be marked ``++volatile++`` in multi-threaded environments, or swapped out for their atomic counterparts: ``++AtomicLong++``, and ``++AtomicDouble++`` to guarantee that their updates are always visible to other threads.
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Similarly, to ensure that updates to 32-bit primitives are visible to all threads, they should also be marked ``++volatile++``.
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=== Noncompliant code example
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[source,java]
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----
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long m = 0; // Noncompliant
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public void increment() {
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m++;
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}
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----
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=== Compliant solution
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[source,java]
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----
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volatile long m = 0;
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public void increment() {
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m++;
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}
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----
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or
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[source,java]
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----
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AtomicLong m = new AtomicLong(0);
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public void increment() {
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m.incrementAndGet();
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}
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----
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== Resources
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* https://wiki.sei.cmu.edu/confluence/x/QTdGBQ[CERT, VNA00-J.] - Ensure visibility when accessing shared primitive variables
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* https://wiki.sei.cmu.edu/confluence/x/zzdGBQ[CERT, VNA05-J.] - Ensure atomicity when reading and writing 64-bit values
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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Mark this "xxx" "volatile" or use an "AtomicXxx" instead.
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=== Highlighting
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``++long|double xxx++``
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'''
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== Comments And Links
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(visible only on this page)
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=== relates to: S3687
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endif::env-github,rspecator-view[]
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