1  /* PR c/69002 */
       2  /* Test we diagnose accessing elements of atomic structures or unions,
       3     which is undefined behavior (C11 6.5.2.3#5).  */
       4  /* { dg-do compile } */
       5  /* { dg-options "-std=c11 -pedantic-errors" } */
       6  
       7  struct S { int x; };
       8  union U { int x; };
       9  
      10  int
      11  fn1 (_Atomic struct S p)
      12  {
      13    int e = 0 && p.x;
      14    return p.x + e; /* { dg-warning "accessing a member .x. of an atomic structure" } */
      15  }
      16  
      17  int
      18  fn2 (_Atomic struct S *p)
      19  {
      20    int e = 1 || p->x;
      21    return p->x + e; /* { dg-warning "accessing a member .x. of an atomic structure" } */
      22  }
      23  
      24  void
      25  fn3 (_Atomic struct S p, int x)
      26  {
      27    p.x = x; /* { dg-warning "accessing a member .x. of an atomic structure" } */
      28  }
      29  
      30  void
      31  fn4 (_Atomic struct S *p, int x)
      32  {
      33    p->x = x; /* { dg-warning "accessing a member .x. of an atomic structure" } */
      34  }
      35  
      36  int
      37  fn5 (_Atomic struct S p)
      38  {
      39    /* This is OK: Members can be safely accessed using a non-atomic
      40       object which is assigned to or from the atomic object.  */
      41    struct S s = p;
      42    return s.x;
      43  }
      44  
      45  int
      46  fn6 (_Atomic struct S *p)
      47  {
      48    struct S s = *p;
      49    return s.x;
      50  }
      51  
      52  int
      53  fn7 (_Atomic union U p)
      54  {
      55    int e = 0 && p.x;
      56    return p.x + e; /* { dg-warning "accessing a member .x. of an atomic union" } */
      57  }
      58  
      59  int
      60  fn8 (_Atomic union U *p)
      61  {
      62    int e = 1 || p->x;
      63    return p->x + e; /* { dg-warning "accessing a member .x. of an atomic union" } */
      64  }
      65  
      66  void
      67  fn9 (_Atomic union U p, int x)
      68  {
      69    p.x = x; /* { dg-warning "accessing a member .x. of an atomic union" } */
      70  }
      71  
      72  void
      73  fn10 (_Atomic union U *p, int x)
      74  {
      75    p->x = x; /* { dg-warning "accessing a member .x. of an atomic union" } */
      76  }
      77  
      78  int
      79  fn11 (_Atomic union U p)
      80  {
      81    /* This is OK: Members can be safely accessed using a non-atomic
      82       object which is assigned to or from the atomic object.  */
      83    union U s = p;
      84    return s.x;
      85  }
      86  
      87  int
      88  fn12 (_Atomic union U *p)
      89  {
      90    union U s = *p;
      91    return s.x;
      92  }