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  1. JDK
  2. JDK-8270882

[lworld] Loose ends in reference default primitive class implementation.

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    Details

    • Type: Bug
    • Status: Open
    • Priority: P4
    • Resolution: Unresolved
    • Affects Version/s: repo-valhalla
    • Fix Version/s: repo-valhalla
    • Component/s: tools
    • Labels:
    • Subcomponent:
    • CPU:
      generic
    • OS:
      generic

      Description

      This is a follow up to https://bugs.openjdk.java.net/browse/JDK-8244231 (https://github.com/openjdk/valhalla/pull/482) for issues
      deliberately deferred from there:

      (1) Types.isSubtype visitor has this code pattern in com.sun.tools.javac.code.Types.TypeRelation#visitClassType

                 @Override
                  public Boolean visitClassType(ClassType t, Type s) {
                      Type sup = asSuper(t, s.tsym);
                      if (sup == null) return false;
                      // If t is an intersection, sup might not be a class type
                      if (!sup.hasTag(CLASS)) return isSubtypeNoCapture(sup, s);
                      return sup.tsym == s.tsym
                          && (t.tsym != s.tsym ||
                              (t.isReferenceProjection() == s.isReferenceProjection() && t.isValueProjection() == s.isValueProjection()))
                           // Check type variable containment
                          && (!s.isParameterized() || containsTypeRecursive(s, sup))
                          && isSubtypeNoCapture(sup.getEnclosingType(),
                                                s.getEnclosingType());
                  }

      The check
      (t.isReferenceProjection() == s.isReferenceProjection() && t.isValueProjection() == s.isValueProjection()))
      should be better coded as
      t.getFlavor() == s.getFlavor()
      but at the moment this is problematic in some cases and needs to be further investigated.

      (2) Same issue with isSameTypeVisitor:

      return t.tsym == s.tsym
                          && t.isReferenceProjection() == s.isReferenceProjection()
                          && t.isValueProjection() == s.isValueProjection()
                          && visit(getEnclosingType(t), getEnclosingType(s))
                          && containsTypeEquivalent(t.getTypeArguments(), s.getTypeArguments());

      should just check for the flavor being the same.

      (3) In the definition of com.sun.tools.javac.code.Types#erasure a TODO has been left in with the comment:
      // Todo: Handle Type variable case.

      (4) There is a TODO task left in LambdaToMethod that needs follow up

      // Todo: Investigate to see if a defect should be reported against runtime lambda machinery

      (5) There is an half hearted attempt to find a place for ACC_REF_DEFAULT in com.sun.tools.classfile.AccessFlags.
      I don't think it belongs there really since it is not a part of the class flags. But I have stuck this in here for now - In javap code to reference ACC_REF_DEFAULT symbolically this is useful (since the compiler's definition from Flags.java is not visible there in javap)

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              Assignee:
              sadayapalam Srikanth Adayapalam
              Reporter:
              sadayapalam Srikanth Adayapalam
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                Dates

                Created:
                Updated: