#include <stdio.h>

/* <sys/linker_set.h> */
#include <mach-o/getsect.h>

#define __LS_VA_STRINGIFY(_x...)    #_x
#define __LS_VA_STRCONCAT(_x,_y)    __LS_VA_STRINGIFY(_x,_y)
#define __LINKER_MAKE_SET(_set, _sym)                   \
    /*__unused*/ /*static*/ void const * /*const*/ __set_##_set##_sym_##_sym        \
    __attribute__ ((section(__LS_VA_STRCONCAT(__DATA,_set)))) = (void *)&_sym
/* */

/* <sys/linker_set.h>: getsectdatafromheader() -> getsectdata() */
static __inline void **
__linker_set_object_begin_fixed(const char *_set)
{
    void *_set_begin;
    unsigned long _size;

    _set_begin = getsectdata("__DATA", _set, &_size);
    return( (void **) _set_begin );
}
static __inline void **
__linker_set_object_limit_fixed(const char *_set)
{
    void *_set_begin;
    unsigned long _size;

    _set_begin = getsectdata("__DATA", _set, &_size);

    return ((void **) ((uintptr_t) _set_begin + _size));
}
/* */

char section[] = "my";

int x = 5;
int y = 10;
int z = 22;

__LINKER_MAKE_SET(my,x);
__LINKER_MAKE_SET(my,y);
__LINKER_MAKE_SET(my,z);

void
main()
{
    printf("Number of entries in section: %d\n",
        __linker_set_object_limit_fixed(section) - __linker_set_object_begin_fixed(section));
    printf("Data of first entry: %d\n", *((int *) *__linker_set_object_begin_fixed(section)) );
}