Atmel CAVR-4 Manual De Usuario

CAVR-4

Part 1. Using the compiler

To set the equivalent option in IAR Embedded Workbench, select 
Project>Options>C/C++ Compiler>Language.

When writing C++ source code for the IAR C/C++ Compiler, there are some benefits 
and some possible quirks that you need to be aware of when mixing C++ features—such 
as classes, and class members—with IAR language extensions, such as IAR-specific 
attributes.

A class type 

class

 and 

struct

 in C++ can have static and non-static data members, 

and static and non-static function members. The non-static function members can be 
further divided into virtual function members, non-virtual function members, 
constructors, and destructors. For the static data members, static function members, and 
non-static non-virtual function members the same rules apply as for statically linked 
symbols outside of a class. In other words, they can have any applicable IAR-specific 
type, memory, and object attribute.

The non-static virtual function members can have any applicable IAR-specific type, 
memory, and object attribute as long as a pointer to the member function is implicitly 
castable to the default function pointer type. The constructors, destructors, and 
non-static data members cannot have any IAR attributes.

For further information about attributes, see Type and object attributes, page 144.

class A {

  public:

   static _ _near int i @ 600;  //Located in near at address 600

   static _ _nearfunc void f(); //Located in nearfunc memory

   _ _nearfunc void g();        //Located in nearfunc memory

   virtual _ _nearfunc void h();//Located in nearfunc memory

};

The 

this

 pointer used for referring to a class object will by default have the data 

memory attribute for the default data pointer type. This means that such a class object 
can only be defined to reside in memory from which pointers can be implicitly casted to 
a default data pointer.