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pointers_to_members 

C++ Specific

Specifies whether a pointer to a class member can be declared before its associated class definition and is used to control the pointer size and the code required to interpret the pointer.

#pragma pointers_to_members( pointer-declaration, [most-general-representation] )

Remarks

You can place a pointers_to_members pragma in your source file as an alternative to using the /vmx compiler options or the inheritance keywords.

The pointer-declaration argument specifies whether you have declared a pointer to a member before or after the associated function definition. The pointer-declaration argument is one of the following two symbols:

Argument Comments

full_generality

Generates safe, sometimes nonoptimal code. You use full_generality if any pointer to a member is declared before the associated class definition. This argument always uses the pointer representation specified by the most-general-representation argument. Equivalent to /vmg.

best_case

Generates safe, optimal code using best-case representation for all pointers to members. Requires defining the class before declaring a pointer to a member of the class. The default is best_case.

The most-general-representation argument specifies the smallest pointer representation that the compiler can safely use to reference any pointer to a member of a class in a translation unit. The argument can be one of the following:

Argument Comments

single_inheritance

The most general representation is single-inheritance, pointer to a member function. Causes an error if the inheritance model of a class definition for which a pointer to a member is declared is ever either multiple or virtual.

multiple_inheritance

The most general representation is multiple-inheritance, pointer to a member function. Causes an error if the inheritance model of a class definition for which a pointer to a member is declared is virtual.

virtual_inheritance

The most general representation is virtual-inheritance, pointer to a member function. Never causes an error. This is the default argument when #pragma pointers_to_members(full_generality) is used.

Example

//   Specify single-inheritance only
#pragma pointers_to_members( full_generality, single_inheritance )

END C++ Specific

See Also

Reference

Pragma Directives