https://issues.dlang.org/show_bug.cgi?id=12799

          Issue ID: 12799
           Summary: Forward reference to nested enum with struct.sizeof
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: minor
          Priority: P1
         Component: DMD
          Assignee: nobody@puremagic.com
          Reporter: dfj1esp02@sneakemail.com

struct A
{
  enum C=A.sizeof;
  enum D=C; //Error: forward reference of variable C
  int a;
}

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