gcc/testsuite/gcc.dg/Wstringop-overflow-43.c

   1 /* PR 96903 - bogus warning on memcpy at negative offset from array end
   2    { dg-do compile }
   3    { dg-options "-O2 -Wall -Wno-array-bounds -ftrack-macro-expansion=0" } */
   4
   5 #include "range.h"
   6
   7 #define INT_MAX    __INT_MAX__
   8 #define INT_MIN    -(INT_MAX - 1)
   9 #define UINT_MAX   (2U * INT_MAX + 1)
  10
  11 typedef __SIZE_TYPE__ size_t;
  12
  13 void* memset (void *, int, size_t);
  14
  15 void sink (void*, ...);
  16
  17 extern char a11[11];
  18 struct S { char a11[11], b; };
  19 extern struct S sa11;
  20
  21 #define T2(dst, off1, off2, n) do {             \
  22     char *_p0 = dst;                            \
  23     char *_p1 = _p0 + (off1);                   \
  24     char *_p2 = _p1 + (off2);                   \
  25     memset (_p2, 0, n);                         \
  26     sink (dst, _p0, _p1, _p2);                  \
  27   } while (0);
  28
  29 #define T1(dst, off, n) T2 (dst, off, 0, n)
  30
  31
  32 void nowarn_memset_array_cst (void)
  33 {
  34   char *p = &a11[11];
  35
  36   T1 (p, -11, 11);
  37   T1 (p, -10, 10);
  38   T1 (p,  -9,  9);
  39   T1 (p,  -8,  8);
  40   T1 (p,  -3,  3);
  41   T1 (p,  -2,  2);
  42   T1 (p,  -1,  1);
  43   T1 (p,   0,  0);
  44
  45   T2 (p, -6, -5, 11);
  46   T2 (p, -6, -4, 10);
  47   T2 (p, -6, -3,  9);
  48   T2 (p, -6, -2,  8);
  49   T2 (p, -6, -1,  7);
  50   T2 (p, -5, -6, 11);
  51   T2 (p, -5, -5, 10);
  52 }
  53
  54 void nowarn_memset_array_rng_int (void)
  55 {
  56   char *p = &a11[11];
  57
  58   int i11 = SR (11, INT_MAX);
  59   int i10 = SR (10, INT_MAX);
  60   int i9  = SR ( 9, INT_MAX);
  61   int i3  = SR ( 3, INT_MAX);
  62   int i2  = SR ( 2, INT_MAX);
  63   int i1  = SR ( 1, INT_MAX);
  64   int i0  = SR ( 0, INT_MAX);
  65
  66   int m11 = SR (INT_MIN, -11);
  67   int m10 = SR (INT_MIN, -10);
  68   int m9  = SR (INT_MIN,  -9);
  69   int m3  = SR (INT_MIN,  -3);
  70   int m2  = SR (INT_MIN,  -2);
  71   int m1  = SR (INT_MIN,  -1);
  72   int m0  = SR (INT_MIN,  -0);
  73
  74   T1 (p, m11, i11);
  75   T1 (p, m10, i10);
  76   T1 (p,  m9,  i9);
  77   T1 (p,  m3,  i3);
  78   T1 (p,  m2,  i2);
  79   T1 (p,  m1,  i1);
  80   T1 (p,  m0,  i0);
  81
  82   T1 (p, m11, i11);
  83   T1 (p, m10, i10);
  84   T1 (p,  m9,  i9);
  85   T1 (p,  m3,  i3);
  86   T1 (p,  m2,  i2);
  87   T1 (p,  m1,  i1);
  88   T1 (p,  m0,  i0);
  89 }
  90
  91
  92 void nowarn_memset_array_rng (void)
  93 {
  94   char *p = &a11[11];
  95
  96   T2 (p, SR (-11, -10), SR ( -2,  -1), UR (11, 12));
  97   T2 (p, SR (-10,  -9), SR ( -1,   0), UR (11, 13));
  98   T2 (p, SR ( -9,  -8), SR ( -2,  -1), UR (11, 14));
  99   T2 (p, SR ( -8,  -7), SR ( -3,  -2), UR (11, 15));
 100   T2 (p, SR ( -7,  -6), SR ( -4,  -3), UR (11, 16));
 101   T2 (p, SR ( -6,  -5), SR ( -5,  -4), UR (11, 17));
 102   T2 (p, SR ( -5,  -4), SR ( -6,  -5), UR (11, 18));
 103   T2 (p, SR ( -4,  -3), SR ( -7,  -6), UR (11, 19));
 104   T2 (p, SR ( -3,  -2), SR ( -8,  -7), UR (11, INT_MAX));
 105   T2 (p, SR ( -2,  -1), SR ( -9,  -8), UR (11, UINT_MAX));
 106   T2 (p, SR ( -1,   0), SR (-10,  -9), UR (11, DIFF_MAX));
 107   T2 (p, SR (  0,   1), SR (-11, -10), UR (11, SIZE_MAX));
 108
 109   T2 (p, SR (DIFF_MIN, -10), SR (DIFF_MIN, -1), UR (10, 12));
 110
 111   T2 (p, SR (-11, -10), SR ( -3,  -1), UR (10, 12))
 112   T2 (p, SR (-11, -10), SR ( -3,  -1), UR (10, 12))
 113 }
 114
 115
 116 void warn_memset_array_rng (void)
 117 {
 118   char *p = &a11[11];
 119   size_t n11_12 = UR (11, 12);
 120   size_t n10_12 = UR (10, 12);
 121
 122   T2 (p, SR (-11, -10), SR ( -3,  -2), n11_12);    // { dg-warning "writing between 11 and 12 bytes into a region of size 0" }
 123   T2 (p, SR (-11, -10), SR ( -3,  -2), n10_12);    // { dg-warning "writing between 10 and 12 bytes into a region of size 0" }
 124 }
 125
 126
 127 void nowarn_memset_anti_range (void)
 128 {
 129   size_t n11 = UR (11, SIZE_MAX);
 130
 131   char *p = &a11[11];
 132
 133   T1 (p, (int)SAR (INT_MIN,      -12), n11);
 134   T1 (p, (int)SAR (    -13,      -13), n11);
 135   T1 (p, (int)SAR (    -13,      -12), n11);
 136   T1 (p, (int)SAR (    -10,        1), n11);
 137   T1 (p, (int)SAR (    -10,       11), n11);
 138   T1 (p, (int)SAR (    -10,  INT_MAX), n11);
 139   T1 (p, (int)SAR (     -1,       -1), n11);
 140   T1 (p, (int)SAR (     -1,        0), n11);
 141   T1 (p, (int)SAR (     -1,       11), n11);
 142   T1 (p, (int)SAR (     -1,  INT_MAX), n11);
 143
 144   T1 (p, SAR (DIFF_MIN,       -12), n11);
 145   T1 (p, SAR (     -13,       -13), n11);
 146   T1 (p, SAR (     -13,       -12), n11);
 147   T1 (p, SAR (     -10,         1), n11);   // { dg-bogus "-Wstringop-overflow" }
 148   T1 (p, SAR (     -10,        11), n11);   // { dg-bogus "-Wstringop-overflow" }
 149   T1 (p, SAR (     -10,  DIFF_MAX), n11);
 150   T1 (p, SAR (     -1,         -1), n11);   // { dg-bogus "-Wstringop-overflow" }
 151   T1 (p, SAR (     -1,          0), n11);   // { dg-bogus "-Wstringop-overflow" }
 152   T1 (p, SAR (     -1,         11), n11);   // { dg-bogus "-Wstringop-overflow" }
 153   T1 (p, SAR (     -1,   DIFF_MAX), n11);
 154 }
 155
 156 void warn_memset_reversed_range (void)
 157 {
 158   size_t n11 = UR (11, SIZE_MAX);
 159
 160   char *p = &a11[11];
 161
 162   /* Since the offset is excessive, either starting before &a11[0]
 163      ot just past &a[11], the region size in the warning should
 164      probably be zero, but accept other sizes too.
 165
 166      The problem isn't detected anymore because the offset is in
 167      the anti-range ~[INT_MIN, -11] which isn't handled.  */
 168   T1 (p, SAR (INT_MIN, -11), n11);      // { dg-warning "writing 11 or more bytes into a region of size \\d+" "" { xfail *-*-* } }
 169
 170   /* The following are represented as ordinary ranges with reversed bounds
 171      and those are handled. */
 172   T1 (p, SAR (INT_MIN,  11), n11);      // { dg-warning "writing 11 or more bytes into a region of size 0" }
 173   T1 (p, SAR (INT_MIN,   1), n11);      // { dg-warning "writing 11 or more bytes into a region of size 0" }
 174   T1 (p, SAR (INT_MIN,   0), n11);      // { dg-warning "writing 11 or more bytes into a region of size 0" }
 175   /* Also represented as a true anti-range.  */
 176   T1 (p, SAR (    -12, -11), n11);      // { dg-warning "writing 11 or more bytes into a region of size \\d+" "" { xfail *-*-* } }
 177   T1 (p, SAR (    -12,  -1), n11);      // { dg-warning "writing 11 or more bytes into a region of size 0" }
 178   T1 (p, SAR (    -11,   0), n11);      // { dg-warning "writing 11 or more bytes into a region of size 0" }
 179   T1 (p, SAR (    -11,  11), n11);      // { dg-warning "writing 11 or more bytes into a region of size 0" }
 180 }