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warning 28309: <parameter_name>: Annotation operands must be integer/enum/pointer types. Void operands and C++ overloaded operators are not supported. Floats are approximated as integers. Types: <typelist>.

You’ve tried to use a void or a function in an annotation expression, and Code Analysis can't handle it. This error typically occurs when an operator== that's implemented as a function is used, but other cases may also occur. Examine the types in <typelist> for clues about what’s wrong.