1  /* PR tree-optimization/80669 - Bad -Wstringop-overflow warnings for stpncpy
       2     { dg-do compile }
       3     { dg-options "-O2 -Wall -Wno-array-bounds -Wno-restrict -Wno-stringop-truncation" } */
       4  
       5  #define SIZE_MAX __SIZE_MAX__
       6  
       7  typedef __SIZE_TYPE__ size_t;
       8  
       9  void sink (char*);
      10  
      11  #define stpncpy (d, s, n)  sink (__builtin_stpncpy (d, s, n))
      12  
      13  size_t value (void);
      14  
      15  static size_t range (size_t min, size_t max)
      16  {
      17    size_t val = value ();
      18    return val < min || max < val ? min : val;
      19  }
      20  
      21  /* Verify that no -Wstringop-overflow warning is issued for stpncpy
      22     with constant size.  (Some tests cause -Wstringop-truncation and
      23     that's expected).  */
      24  void test_cst (char *d)
      25  {
      26    __builtin_stpncpy (d, "123", 0);
      27    __builtin_stpncpy (d, "123", 1);
      28    __builtin_stpncpy (d, "123", 2);
      29    __builtin_stpncpy (d, "123", 3);
      30    __builtin_stpncpy (d, "123", 4);
      31    __builtin_stpncpy (d, "123", 5);
      32    __builtin_stpncpy (d, "123", 999);
      33  
      34    size_t n = SIZE_MAX / 2;
      35  
      36    __builtin_stpncpy (d, "123", n);
      37  
      38    __builtin_stpncpy (d, "123", n + 1);    /* { dg-warning "specified bound \[0-9\]+ exceeds maximum object size \[0-9\]+" } */
      39  }
      40  
      41  
      42  /* Verify that no -Wstringop-overflow warning is issued for stpncpy
      43     with size in some range.  */
      44  void test_rng (char *d)
      45  {
      46  #define R(min, max) range (min, max)
      47  
      48    __builtin_stpncpy (d, "123", R (0, 1));
      49    __builtin_stpncpy (d, "123", R (0, 2));
      50    __builtin_stpncpy (d, "123", R (0, 3));
      51    __builtin_stpncpy (d, "123", R (0, 4));
      52    __builtin_stpncpy (d, "123", R (0, 5));
      53  
      54    __builtin_stpncpy (d, "123", R (1, 2));
      55    __builtin_stpncpy (d, "123", R (1, 3));
      56    __builtin_stpncpy (d, "123", R (1, 4));
      57    __builtin_stpncpy (d, "123", R (1, 5));
      58  
      59    __builtin_stpncpy (d, "123", R (2, 3));
      60    __builtin_stpncpy (d, "123", R (2, 4));
      61    __builtin_stpncpy (d, "123", R (2, 5));
      62  
      63    __builtin_stpncpy (d, "123", R (3, 4));
      64    __builtin_stpncpy (d, "123", R (3, 5));
      65  
      66    __builtin_stpncpy (d, "123", R (4, 5));
      67  
      68    __builtin_stpncpy (d, "123", R (5, 6));
      69  
      70    __builtin_stpncpy (d, "123", R (12345, 23456));
      71  
      72    size_t n = SIZE_MAX / 2;
      73  
      74    __builtin_stpncpy (d, "123", R (n - 1, n + 1));
      75  
      76    __builtin_stpncpy (d, "123", R (n + 1, n + 2));   /* { dg-warning "specified bound between \[0-9\]+ and \[0-9\]+ exceeds maximum object size \[0-9\]+" } */
      77  }