if types.IdenticalIgnoreTags(src.Underlying(), dst.Underlying()) {
		return ir.OCONVNOP, ""
	}

	// 3. src and dst are unnamed pointer types and, ignoring struct tags,
	// their base types have identical underlying types.
	if src.IsPtr() && dst.IsPtr() && src.Sym() == nil && dst.Sym() == nil {
		if types.IdenticalIgnoreTags(src.Elem().Underlying(), dst.Elem().Underlying()) {