1  #include <omp.h>
       2  #include <stdlib.h>
       3  
       4  struct S
       5  {
       6    int a, b, c, d;
       7  };
       8  typedef struct S S;
       9  
      10  int main (void)
      11  {
      12    int d = omp_get_default_device ();
      13    int id = omp_get_initial_device ();
      14  
      15    if (d < 0 || d >= omp_get_num_devices ())
      16      d = id;
      17  
      18    S s;
      19    #pragma omp target enter data map (alloc: s.a, s.b, s.c, s.d)
      20    #pragma omp target enter data map (alloc: s.c)
      21    #pragma omp target enter data map (alloc: s.b, s.d)
      22    #pragma omp target enter data map (alloc: s.a, s.c, s.b)
      23  
      24    #pragma omp target exit data map (release: s.a)
      25    #pragma omp target exit data map (release: s.d)
      26    #pragma omp target exit data map (release: s.c)
      27    #pragma omp target exit data map (release: s.b)
      28  
      29    /* OpenMP 5.0 structure element mapping rules describe that elements of same
      30       structure variable should allocate/deallocate in a uniform fashion, so
      31       all elements of 's' should be removed together by above 'exit data's.  */
      32    if (d != id)
      33      {
      34        if (omp_target_is_present (&s, d))
      35  	abort ();
      36        if (omp_target_is_present (&s.a, d))
      37  	abort ();
      38        if (omp_target_is_present (&s.b, d))
      39  	abort ();
      40        if (omp_target_is_present (&s.c, d))
      41  	abort ();
      42        if (omp_target_is_present (&s.d, d))
      43  	abort ();
      44      }
      45  
      46    return 0;
      47  }