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#include <iostream>
using namespace std;
 
    #define DECLARE_SELF(Type) \
        typedef Type TySelf; /**< @brief type of this class */ \
        /** checks the consistency of TySelf type (calling it has no effect) */ \
        void self_check() \
        { \
            static_assert(std::is_same<decltype(*((TySelf*)(0))), \
                decltype(*this)>::value, "TySelf is not what it should be"); \
        } \
        enum { static_self_check_token = __LINE__ }; \
        static_assert(int(static_self_check_token) == \
            int(TySelf::static_self_check_token), \
            "TySelf is not what it should be")
 
    struct ABC {
        DECLARE_SELF(ABC);
    };
 
    struct XYZ {
        DECLARE_SELF(ABC); // fails
    	//DECLARE_SELF(XYZ); // runs
    };
 
    template <class MyArg>
    struct XYZt {
        DECLARE_SELF(ABC); // fails, if XYZt is instantiated
        //DECLARE_SELF(XYZt); // runs
    };
 
 
int main() {
	XYZt<int> instantiate_me;
 
	return 0;
}

prog.cpp:14:9: error: static assertion failed: TySelf is not what it should be
         static_assert(int(static_self_check_token) == \
         ^
prog.cpp:23:9: note: in expansion of macro ‘DECLARE_SELF’
         DECLARE_SELF(ABC); // fails
         ^
prog.cpp: In member function ‘void XYZ::self_check()’:
prog.cpp:10:13: error: static assertion failed: TySelf is not what it should be
             static_assert(std::is_same<decltype(*((TySelf*)(0))), \
             ^
prog.cpp:23:9: note: in expansion of macro ‘DECLARE_SELF’
         DECLARE_SELF(ABC); // fails
         ^
prog.cpp: In instantiation of ‘struct XYZt<int>’:
prog.cpp:35:12:   required from here
prog.cpp:14:9: error: static assertion failed: TySelf is not what it should be
         static_assert(int(static_self_check_token) == \
         ^
prog.cpp:29:9: note: in expansion of macro ‘DECLARE_SELF’
         DECLARE_SELF(ABC); // fails, if XYZt is instantiated
         ^
prog.cpp: In function ‘int main()’:
prog.cpp:35:12: warning: unused variable ‘instantiate_me’ [-Wunused-variable]
  XYZt<int> instantiate_me;
            ^

Standard output is empty