VARIANTDUP

Message        The anonymous struct or union member "<member name>"
               duplicates the name of a member in the enclosing
               struct or union.

Description    As members of an anonymous structure or union are
               promoted to membership of the enclosing struct/union
               type, the names of each element of the anonymous
               struct/union must not match an element name in the
               enclosing struct/union.  This message can also be
               output when the variant_struct or variant_union
               syntax is used instead of the anonymous struct/union.

User Action    Choose a new name for either the offending anonymous
               struct/union member or the matching member of the
               enclosing type.