#include <stdio.h>

#define SEARCH_PATH /home/user/ordner/bla/

#define STR(X) #X
#define STR2(X) STR(X)
#define CONCAT(X,Y) X##Y
#define EXPAND(x) x

#define MAKE_PATH(x) STR2(EXPAND(SEARCH_PATH)x)
#define MAKRO(x) MAKE_PATH(x)

#include MAKRO(fileA.hpp)

int main(void) {
	printf("%s", MAKRO(fileA.hpp));
	return 0;
}