For the latest documentation on Visual Studio 2017 RC, see Visual Studio 2017 RC Documentation.

warning C28024: The function pointer being assigned to is annotated with the function class <class>, which is not contained in the function class(es) <classlist>.

This warning is reported when both functions were annotated with a function class, but the classes do not match.

this warning is issued when a function pointer has a _Function_class_ annotation that specifies that only functions of a particular functional class should be assigned to it. In an assignment or implied assignment in a function call, the source and target must be of the same function class, but the function classes do not match.