gcc/testsuite/c-c++-common/attr-nonstring-8.c

   1 /* PR middle-end/85602 - -Wsizeof-pointer-memaccess for strncat with size
   2    of source
   3    { dg-do compile }
   4    { dg-options "-O2 -Wno-array-bounds -Wsizeof-pointer-memaccess -Wstringop-truncation -ftrack-macro-expansion=0" } */
   5
   6 #include "../gcc.dg/range.h"
   7
   8 typedef __SIZE_TYPE__ size_t;
   9
  10 #if __cplusplus
  11 extern "C" {
  12 #endif
  13
  14 char* strcpy (char*, const char*);
  15 size_t strlen (const char*);
  16 char* strncat (char*, const char*, __SIZE_TYPE__);
  17 char* strncpy (char*, const char*, __SIZE_TYPE__);
  18
  19 #if __cplusplus
  20 }
  21 #endif
  22
  23 #define NONSTR __attribute__ ((nonstring))
  24
  25 NONSTR char nd3[3];
  26 NONSTR char nd4[4];
  27 NONSTR char nd5[5];
  28
  29 NONSTR char ns3[3];
  30 NONSTR char ns4[4];
  31 NONSTR char ns5[5];
  32
  33 NONSTR char* pns;
  34
  35 void sink (void*, ...);
  36
  37 #define T(call) sink (call)
  38
  39 /* Verify that for a nonstring source array of an unknown length
  40    a warning is issued only when the bound exceeds the array size.  */
  41
  42 void test_strncat_nonstring_cst (char *d)
  43 {
  44   T (strncat (d, ns3, 1));
  45   T (strncat (d, ns3, 2));
  46   T (strncat (d, ns3, 3));
  47   T (strncat (d, ns3, sizeof ns3));
  48   T (strncat (d, ns3, 4));     /* { dg-warning "argument 2 declared attribute .nonstring. is smaller than the specified bound 4" } */
  49
  50   T (strncat (d, ns4, 1));
  51   T (strncat (d, ns4, 2));
  52   T (strncat (d, ns4, 3));
  53   T (strncat (d, ns4, 4));
  54   T (strncat (d, ns4, sizeof ns4));
  55   T (strncat (d, ns4, 5));     /* { dg-warning "argument 2 declared attribute .nonstring. is smaller than the specified bound 5" } */
  56
  57   T (strncat (nd3, ns3, 1));
  58   T (strncat (nd3, ns3, 2));
  59   T (strncat (nd3, ns3, 3));     /* { dg-warning "specified bound 3 equals destination size" } */
  60   T (strncat (nd3, ns3, 4));     /* { dg-warning "argument 2 declared attribute .nonstring. is smaller than the specified bound 4" } */
  61   /* { dg-warning "specified bound 4 exceeds destination size 3" "" { target *-*-* } .-1 } */
  62
  63   T (strncat (d, pns, sizeof pns));   /* { dg-warning "argument to .sizeof. in .strncat. call is the same expression as the source" } */
  64 }
  65
  66
  67 void test_strncat_nonstring_var (char *d, size_t n)
  68 {
  69   /* In the following the bound coulld apply to either the destination
  70      or the source.  The expected use of strncat() is to pass it as
  71      the bound DSIZE - strlen(D) - 1 so the call below is diagnosed.  */
  72   T (strncat (d, ns3, n));            /* { dg-warning "argument 2 declared attribute .nonstring." } */
  73
  74   T (strncat (d, ns3, UR (0, 1)));
  75   T (strncat (d, ns3, UR (1, 2)));
  76   T (strncat (d, ns3, UR (2, 3)));
  77   T (strncat (d, ns3, UR (3, 4)));    /* { dg-warning "argument 2 declared attribute 'nonstring' may be smaller than the specified bound \\\[3, 4]" } */
  78   T (strncat (d, ns3, UR (4, 5)));    /* { dg-warning "argument 2 declared attribute 'nonstring' is smaller than the specified bound \\\[4, 5]" } */
  79
  80   /* Verify that the call below (the intended use of strncat()) is
  81      also diagnosed.  */
  82   T (strncat (d, ns3, 256 - strlen (d) - 1));   /* { dg-warning "argument 2 declared attribute .nonstring." } */
  83
  84   T (strncat (nd3, ns5, UR (0, 1)));
  85   T (strncat (nd3, ns5, UR (1, 2)));
  86   T (strncat (nd3, ns5, UR (2, 3)));
  87   T (strncat (nd3, ns5, UR (3, 4)));
  88   T (strncat (nd3, ns5, UR (4, 5)));  /* { dg-warning "specified bound between 4 and 5 exceeds destination size 3" } */
  89
  90   T (strncat (nd5, ns3, UR (0, 1)));
  91   T (strncat (nd5, ns3, UR (1, 2)));
  92   T (strncat (nd5, ns3, UR (2, 3)));
  93   T (strncat (nd5, ns3, UR (3, 4)));  /* { dg-warning "argument 2 declared attribute 'nonstring' may be smaller than the specified bound \\\[3, 4]" } */
  94 }
  95
  96 /* Verify that for a nonstring source array of a known length (i.e.,
  97    a nonstring array containing a nul-terminated string) a warning
  98    is issued only for certain truncation.
  99
 100    The test cases are split up to work around bug 81343 (or one like
 101    it).  */
 102
 103 void test_strncat_string_1_1 (char *d)
 104 {
 105   strcpy (ns3, "1");
 106   T (strncat (d, ns3, 1));    /* { dg-warning "output truncated before terminating nul copying 1 byte from a string of the same length" } */
 107 }
 108
 109 void test_strncat_string_1_2 (char *d)
 110 {
 111   strcpy (ns3, "1");
 112   T (strncat (d, ns3, 2));
 113 }
 114
 115 void test_strncat_string_1_3 (char *d)
 116 {
 117   strcpy (ns3, "1");
 118   T (strncat (d, ns3, 3));
 119 }
 120
 121 void test_strncat_string_2_1 (char *d)
 122 {
 123   strcpy (ns3, "12");
 124   T (strncat (d, ns3, 1));    /* { dg-warning "output truncated copying 1 byte from a string of length 2" } */
 125 }
 126
 127 void test_strncat_string_2_2 (char *d)
 128 {
 129   strcpy (ns3, "12");
 130   T (strncat (d, ns3, 2));    /* { dg-warning "output truncated before terminating nul copying 2 bytes from a string of the same length" } */
 131 }
 132
 133 void test_strncat_string_2_3 (char *d)
 134 {
 135   strcpy (ns3, "12");
 136   T (strncat (d, ns3, 3));
 137 }
 138
 139
 140 void test_strcncpy_nonstring_cst (char *d)
 141 {
 142   T (strncpy (d, ns3, 1));
 143   T (strncpy (d, ns3, 2));
 144   T (strncpy (d, ns3, 3));
 145   T (strncpy (d, ns3, sizeof ns3));
 146   T (strncpy (d, ns3, 4));      /* { dg-warning "argument 2 declared attribute .nonstring. is smaller than the specified bound 4" } */
 147 }