gcc/testsuite/gcc.dg/Warray-bounds-29.c

   1 /* PR tree-optimization/83776: missing -Warray-bounds indexing past the end
   2    of a string literal
   3    Test to exercise warnings for computations of otherwise in-bounds indices
   4    into strings that temporarily exceed the bounds of the string.
   5    { dg-do compile }
   6    { dg-options "-O2 -Warray-bounds=2 -ftrack-macro-expansion=0" } */
   7
   8 #include "range.h"
   9
  10 #define MAX DIFF_MAX
  11 #define MIN DIFF_MIN
  12
  13 typedef __WCHAR_TYPE__ wchar_t;
  14
  15 void sink (int, ...);
  16
  17 #define T(expr)   sink (0, expr)
  18
  19 void test_narrow (void)
  20 {
  21   int i = SR (1, 2);
  22
  23   const char *p0 = "12";
  24   const char *p1 = p0 + i;    /* points at '2' or beyond */
  25   const char *p2 = p1 + i;    /* points at '\0' or beyond */
  26   const char *p3 = p2 + i;    /* points just past the end */
  27   const char *p4 = p3 + i;    /* invalid */
  28
  29   T (p0[-1]);                 /* { dg-warning "array subscript \(-1|\[0-9\]+) is outside array bounds of .char\\\[3]." } */
  30   T (p0[0]);
  31   T (p0[1]);
  32   T (p0[2]);
  33   T (p0[3]);                  /* { dg-warning "array subscript 3 is outside array bounds of .char\\\[3]." } */
  34
  35   T (&p0[-1]);                /* { dg-warning "array subscript \(-1|\[0-9\]+) is \(above|below|outside\) array bounds of .char\\\[3]." } */
  36   T (&p0[0]);
  37   T (&p0[1]);
  38   T (&p0[2]);
  39   T (&p0[3]);
  40   T (&p0[4]);                 /* { dg-warning "array subscript 4 is \(above|outside\) array bounds of .char\\\[3]." } */
  41
  42   T (p1[-3]);                 /* { dg-warning "array subscript \\\[-2, -1] is outside array bounds of .char\\\[3]." } */
  43   T (p1[-2]);
  44   T (p1[-1]);
  45   T (p1[ 0]);
  46   T (p1[ 1]);
  47   T (p1[ 2]);                 /* { dg-warning "array subscript 3 is outside array bounds of .char\\\[3]." } */
  48   T (p1[ 3]);                 /* { dg-warning "array subscript \\\[4, 5] is outside array bounds of .char\\\[3]." } */
  49
  50   T (&p1[-3]);                /* { dg-warning "array subscript \\\[-2, -1] is outside array bounds of .char\\\[3]." "bug" { xfail *-*-* } } */
  51   T (&p1[-2]);
  52   T (&p1[-1]);
  53   T (&p1[ 0]);
  54   T (&p1[ 1]);
  55   T (&p1[ 2]);
  56   T (&p1[ 3]);                /* { dg-warning "array subscript \\\[4, 6] is outside array bounds of .char\\\[3]." "bug" { xfail *-*-* } } */
  57
  58   T (p2[-4]);                 /* { dg-warning "subscript \\\[-2, -1\\\] is outside array bounds of .char\\\[3]." } */
  59   T (p2[-3]);
  60   T (p2[-2]);
  61   T (p2[-1]);
  62   T (p2[ 0]);
  63
  64   /* Even though the lower bound of p3's offsets is in bounds, in order
  65      to subtract 4 from p3 and get a dereferenceable pointer its value
  66      would have to be out-of-bounds.  */
  67   T (p3[-4]);                 /* { dg-warning "array subscript -1 is outside array bounds of .char\\\[3]." } */
  68   T (p3[-3]);
  69   T (p3[-2]);
  70   T (p3[-1]);
  71   T (p3[ 0]);                 /* { dg-warning "array subscript 3 is outside array bounds of .char\\\[3]." } */
  72
  73   T (p4[-4]);                 /* { dg-warning "intermediate array offset 4 is outside array bounds of .char\\\[3]." } */
  74   T (p4[-3]);                 /* { dg-warning "intermediate array offset 4 is outside array bounds of .char\\\[3]." } */
  75   T (p4[-2]);                 /* { dg-warning "intermediate array offset 4 is outside array bounds of .char\\\[3]." } */
  76
  77   /* The final subscripts below are invalid.  */
  78   T (p4[-1]);                 /* { dg-warning "array subscript 3 is outside array bounds of .char\\\[3]." } */
  79   T (p4[ 0]);                 /* { dg-warning "array subscript \\\[4, 5] is outside array bounds of .char\\\[3]." } */
  80 }
  81
  82
  83 void test_narrow_vflow (void)
  84 {
  85   int i = SR (DIFF_MAX - 2, DIFF_MAX);
  86   int j = SR (1, DIFF_MAX);
  87
  88   const char *p0 = "123";
  89   const char *p1 = p0 + i;    /* points at '2' or beyond */
  90   const char *p2 = p1 + i;    /* points at '\0' or beyond */
  91   const char *p3 = p2 + i;    /* points just past the end */
  92   const char *p4 = p3 + i;    /* invalid */
  93 }
  94
  95
  96 void test_wide (void)
  97 {
  98   int i = SR (1, 2);
  99
 100   const wchar_t *p0 = L"123";
 101   const wchar_t *p1 = p0 + i;    /* points at L'2' or beyond */
 102   const wchar_t *p2 = p1 + i;    /* points at L'3' or beyond */
 103   const wchar_t *p3 = p2 + i;    /* points at L'\0' or beyond */
 104   const wchar_t *p4 = p3 + i;    /* points just past the end */
 105   const wchar_t *p5 = p4 + i;    /* invalid */
 106
 107   T (p0[0]);
 108   T (p0[1]);
 109   T (p0[2]);
 110   T (p0[3]);
 111   T (p0[4]);                  /* { dg-warning "array subscript 4 is outside array bounds of .\[a-z \]+\\\[4]." } */
 112
 113   T (p1[-1]);
 114   T (p1[ 0]);
 115   T (p1[ 1]);
 116   T (p1[ 2]);
 117   T (p1[ 3]);                  /* { dg-warning "array subscript 4 is outside array bounds of .\[a-z \]+\\\[4]." } */
 118
 119   T (&p1[-1]);
 120   T (&p1[ 0]);
 121   T (&p1[ 1]);
 122   T (&p1[ 2]);
 123   T (&p1[ 3]);
 124   T (&p1[ 4]);                 /* { dg-warning "array subscript \\\[5, 6] is outside array bounds of .\[a-z \]+\\\[4]." "bug" { xfail *-*-* } } */
 125
 126   T (p2[-5]);                 /* { dg-warning "array subscript \\\[-3, -1] is outside array bounds of .\[a-z \]+\\\[4]." } */
 127   T (p2[-4]);
 128   T (p2[-3]);
 129   T (p2[-2]);
 130   T (p2[-1]);
 131   T (p2[ 0]);
 132
 133   /* Even though the lower bound of p3's offsets is in bounds, in order
 134      to subtract 5 from p3 and get a dereferenceable pointer its value
 135      would have to be out-of-bounds.  */
 136   T (p3[-5]);                 /* { dg-warning "array subscript \\\[-2, -1\\\] is outside array bounds of .\[a-z \]+\\\[4]." } */
 137   T (p3[-4]);
 138   T (p3[-3]);
 139   T (p3[-2]);
 140   T (p3[-1]);
 141   T (p3[ 0]);
 142   T (p3[ 1]);                 /* { dg-warning "array subscript 4 is outside array bounds of .\[a-z \]+\\\[4]." } */
 143
 144   T (p4[-5]);                 /* { dg-warning "array subscript -1 is outside array bounds of .\[a-z \]+\\\[4]." } */
 145   T (p4[-4]);
 146   T (p4[-3]);
 147   T (p4[-2]);
 148   T (p4[-1]);
 149   T (p4[ 0]);                 /* { dg-warning "array subscript 4 is outside array bounds of .\[a-z \]+\\\[4]." } */
 150 }