gcc/testsuite/gcc.dg/builtin-stpncpy.c

   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 size \[0-9\]+ 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 size between \[0-9\]+ and \[0-9\]+ exceeds maximum object size \[0-9\]+" } */
  77 }