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  1. JDK
  2. JDK-8012464

NMT: classes should not derive from _ValueObj, use VALUE_OBJ_CLASS_SPEC instead

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        David Holmes pointed out that some of NMT classes derive from _ValueObj, but should use VALUE_OBJ_CLASS_SPEC instead.


        // Portability note: Certain compilers (e.g. gcc) will
        // always make classes bigger if it has a superclass, even
        // if the superclass does not have any virtual methods or
        // instance fields. The HotSpot implementation relies on this
        // not to happen. So never make a ValueObj class a direct subclass
        // of this object, but use the VALUE_OBJ_CLASS_SPEC class instead, e.g.,
        // like this:
        //
        // class A VALUE_OBJ_CLASS_SPEC {
        // ...
        // }
        //
        // With gcc and possible other compilers the VALUE_OBJ_CLASS_SPEC can
        // be defined as a an empty string "".
        //

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                • Assignee:
                  zgu Zhengyu Gu
                  Reporter:
                  zgu Zhengyu Gu
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