https://issues.dlang.org/show_bug.cgi?id=20814

          Issue ID: 20814
           Summary: Fail to compile with scope - what is reason for
                    restriction?
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: apz28@hotmail.com

Fail with message "Error: no size because of forward references"

    struct S
    {
        alias D = void delegate(scope ref S value);

        int v;
        D dg;
    }

Remove 'scope' and it is fine

    struct S
    {
        alias D = void delegate(ref S value);

        int v;
        D dg;
    }

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