gcc/testsuite/c-c++-common/attr-nonstring-6.c

   1 /* PR 85623 - strncmp() warns about attribute 'nonstring' incorrectly
   2    in -Wstringop-overflow
   3   { dg-do compile }
   4   { dg-options "-O2 -Wstringop-overflow -ftrack-macro-expansion=0" } */
   5
   6 #include "../gcc.dg/range.h"
   7
   8 #if __cplusplus
   9 extern "C" {
  10 #endif
  11
  12 extern int strcmp (const char*, const char*);
  13 extern int strncmp (const char*, const char*, size_t);
  14 extern int strncasecmp (const char*, const char*, size_t);
  15
  16 extern size_t strspn (const char*, const char*);
  17 extern size_t strcspn (const char*, const char*);
  18
  19 #if __cplusplus
  20 }
  21 #endif
  22
  23 #define S26 "0123456789abcdefghijklmnopqrstuvwxyz"
  24 #define S(n) (S26 + sizeof S26 - 1 - (n))
  25
  26 char __attribute__ ((nonstring)) a3[3];
  27 char __attribute__ ((nonstring)) a5[5];
  28
  29 void sink (int);
  30
  31 #define T(call)   sink (call)
  32
  33 void test_strcmp_cst (void)
  34 {
  35   /* Verify that no warning is issued for strcmp() calls with a non-string
  36      array argument when the other argument is a string whose length is
  37      less than the size of the array.  Because the function stops reading
  38      at the first nul character there is no chance that it will read past
  39      the end of the array.  */
  40   T (strcmp (S (0), a3));
  41   T (strcmp (S (1), a3));
  42   T (strcmp (S (2), a3));
  43   /* The following reads a3[3].  */
  44   T (strcmp (S (3), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  45   /* The following also reads past the end of a3.  */
  46   T (strcmp (S (9), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  47
  48   T (strcmp (a3, S (0)));
  49   T (strcmp (a3, S (1)));
  50   T (strcmp (a3, S (2)));
  51   T (strcmp (a3, S (3)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  52   T (strcmp (a3, S (9)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  53 }
  54
  55
  56 void test_strcmp_range (const char *s)
  57 {
  58   s = signed_value () < 0 ? S (0) : S (1);
  59   T (strcmp (a3, s));
  60
  61   s = signed_value () < 0 ? S (0) : S (2);
  62   T (strcmp (a3, s));
  63
  64   s = signed_value () < 0 ? S (0) : S (3);
  65   T (strcmp (a3, s));       /* { dg-warning "\\\[-Wstringop-overflow" } */
  66
  67   s = signed_value () < 0 ? S (1) : S (2);
  68   T (strcmp (a3, s));
  69
  70   s = signed_value () < 0 ? S (1) : S (3);
  71   T (strcmp (a3, s));       /* { dg-warning "\\\[-Wstringop-overflow" } */
  72
  73   s = signed_value () < 0 ? S (3) : S (4);
  74   T (strcmp (a3, s));       /* { dg-warning "\\\[-Wstringop-overflow" } */
  75 }
  76
  77
  78 void test_strncmp_cst (void)
  79 {
  80   T (strncmp (S (0), a3, 1));
  81   T (strncmp (S (1), a3, 2));
  82   T (strncmp (S (2), a3, 3));
  83   T (strncmp (S (3), a3, 3));
  84   T (strncmp (S (3), a3, 4));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  85
  86   T (strncmp (S (9), a3, 3));
  87   T (strncmp (S (9), a3, 4));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  88   T (strncmp (S (9), a3, 5));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  89
  90   T (strncmp (a3, S (0), 1));
  91   T (strncmp (a3, S (1), 2));
  92   T (strncmp (a3, S (2), 3));
  93   T (strncmp (a3, S (3), 3));
  94   T (strncmp (a3, S (3), 4));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  95
  96   T (strncmp (a3, S (9), 3));
  97   T (strncmp (a3, S (9), 4));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  98   T (strncmp (a3, S (9), 5));   /* { dg-warning "\\\[-Wstringop-overflow" } */
  99 }
 100
 101 void test_strncmp_range (const char *s)
 102 {
 103   T (strncmp (a3, S (2), UR (0, 3)));
 104   T (strncmp (a3, S (2), UR (1, 4)));
 105   T (strncmp (a3, S (2), UR (2, 5)));
 106   T (strncmp (a3, S (2), UR (3, 6)));
 107   T (strncmp (a3, S (2), UR (4, 7)));
 108
 109   T (strncmp (a3, S (5), UR (0, 3)));
 110   T (strncmp (a3, S (5), UR (1, 4)));
 111   T (strncmp (a3, S (5), UR (2, 5)));
 112   T (strncmp (a3, S (5), UR (3, 6)));
 113   T (strncmp (a3, S (5), UR (4, 7)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 114   T (strncmp (a3, S (5), UR (7, 9)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 115
 116   s = signed_value () < 0 ? S (0) : S (1);
 117   T (strncmp (a3, s, UR (1, 3)));
 118   T (strncmp (a3, s, UR (2, 5)));
 119
 120   s = signed_value () < 0 ? S (2) : S (5);
 121   T (strncmp (a3, s, UR (1, 3)));
 122
 123   s = signed_value () < 0 ? S (2) : S (5);
 124   T (strncmp (a3, s, UR (1, 4)));
 125   T (strncmp (a3, s, UR (2, 5)));
 126   T (strncmp (a3, s, UR (3, 6)));
 127   T (strncmp (a3, s, UR (4, 7)));       /* { dg-warning "\\\[-Wstringop-overflow" } */
 128 }
 129
 130 void test_strncasecmp (void)
 131 {
 132   T (strncasecmp (S (0), a3, 1));
 133   T (strncasecmp (S (1), a3, 2));
 134   T (strncasecmp (S (2), a3, 3));
 135   T (strncasecmp (S (3), a3, 3));
 136   T (strncasecmp (S (3), a3, 4));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 137
 138   T (strncasecmp (S (9), a3, 3));
 139   T (strncasecmp (S (9), a3, 4));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 140   T (strncasecmp (S (9), a3, 5));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 141
 142   T (strncasecmp (a3, S (0), 1));
 143   T (strncasecmp (a3, S (1), 2));
 144   T (strncasecmp (a3, S (2), 3));
 145   T (strncasecmp (a3, S (3), 3));
 146   T (strncasecmp (a3, S (3), 4));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 147
 148   T (strncasecmp (a3, S (9), 3));
 149   T (strncasecmp (a3, S (9), 4));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 150   T (strncasecmp (a3, S (9), 5));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 151 }
 152
 153 void test_strspn (void)
 154 {
 155   /* strspn must traverse all characters in the second argument except
 156      when the first string is empty. */
 157   T (strspn (S (0), a3));
 158   T (strspn (S (1), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 159   T (strspn (S (2), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 160   T (strspn (S (3), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 161   T (strspn (S (9), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 162
 163   /* Similarly, strspn must traverse all characters in the first argument
 164      except when the second string is empty. */
 165   T (strspn (a3, S (0)));
 166   T (strspn (a3, S (1)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 167   T (strspn (a3, S (2)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 168   T (strspn (a3, S (3)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 169   T (strspn (a3, S (9)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 170 }
 171
 172 void test_strcspn (void)
 173 {
 174   T (strcspn (S (0), a3));
 175   T (strcspn (S (1), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 176   T (strcspn (S (2), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 177   T (strcspn (S (3), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 178   T (strcspn (S (9), a3));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 179
 180   T (strcspn (a3, S (0)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 181   T (strcspn (a3, S (1)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 182   T (strcspn (a3, S (2)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 183   T (strcspn (a3, S (3)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 184   T (strcspn (a3, S (9)));   /* { dg-warning "\\\[-Wstringop-overflow" } */
 185 }