gcc/testsuite/gcc.dg/Wstringop-overflow-55.c

   1 /* Verify that offsets in "anti-ranges" are handled correctly.
   2    { dg-do compile }
   3    { dg-options "-O2 -Wall -ftrack-macro-expansion=0 -fno-ipa-icf" } */
   4
   5 typedef __PTRDIFF_TYPE__ ptrdiff_t;
   6 typedef __SIZE_TYPE__    size_t;
   7
   8 void* memset (void*, int, size_t);
   9
  10 void sink (void*, ...);
  11 #define T(x) sink (x)
  12
  13
  14 void int_range_add_sub_ (int i, int j)
  15 {
  16   if (i < 1) i = 1;
  17   if (j > -1) j = -1;
  18
  19   char ca5[5];              // { dg-message "at offset \\\[1, 5]" "note" }
  20   char *p0 = ca5;           // offset
  21   char *p1 = p0 + i;        //  1-5
  22   char *p2 = p1 + i;        //  2-5
  23   char *p3 = p2 + j;        //  0-4
  24   char *p4 = p3 + j;        //  0-3
  25   char *p5 = p4 + j;        //  0-2
  26   char *p6 = p5 + j;        //  0-1
  27   char *p7 = p6 + i;        //  1-2
  28
  29   memset (p7, 0, 5);        // { dg-warning "writing 5 bytes into a region of size 4" }
  30
  31   sink (p0, p1, p2, p3, p4, p5, p6, p7);
  32 }
  33
  34
  35 void ruint_arint_add (unsigned i, int j)
  36 {
  37   i |= 1;   // [1, UINT_MAX]
  38   j |= 1;   // [INT_MIN + 1, -1] U [1, INT_MAX]
  39
  40   char a[5];                // { dg-message "at offset \\\[1, 5]" "note" }
  41   char *p0 = a;             // offset
  42   char *p1 = p0 + i;        //  1-5
  43   T (memset (p1, 0, 4));
  44
  45   char *p2 = p1 + j;        //  0-5
  46   T (memset (p2, 0, 5));
  47
  48   char *p3 = p2 + i;        //  1-5
  49   T (memset (p3, 0, 4));
  50
  51   char *p4 = p3 + j;        //  0-5
  52   T (memset (p4, 0, 5));
  53
  54   char *p5 = p4 + i;        //  1-5
  55   T (memset (p5, 0, 4));
  56
  57   char *p6 = p5 + j;        //  0-5
  58   T (memset (p6, 0, 5));
  59
  60   char *p7 = p6 + i;        //  1-5
  61   T (memset (p7, 0, 5));    // { dg-warning "writing 5 bytes into a region of size 4" "" }
  62 }
  63
  64
  65 void warn_ptrdiff_anti_range_add (ptrdiff_t i)
  66 {
  67   i |= 1;
  68
  69   char ca5[5];              // { dg-message "at offset \\\[1, 5]" "pr?????" }
  70   char *p0 = ca5;           // offset
  71   char *p1 = p0 + i;        //  1-5
  72   char *p2 = p1 + i;        //  2-5
  73   char *p3 = p2 + i;        //  3-5
  74   char *p4 = p3 + i;        //  4-5
  75   char *p5 = p4 + i;        //   5
  76
  77   memset (p5, 0, 5);        // { dg-warning "writing 5 bytes into a region of size" "pr?????" }
  78
  79   sink (p0, p1, p2, p3, p4, p5);
  80 }
  81
  82 void warn_int_anti_range (int i)
  83 {
  84   i |= 1;
  85
  86   char ca5[5];              // { dg-message "at offset \\\[1, 5]" "pr?????" }
  87   char *p0 = ca5;           // offset
  88   char *p1 = p0 + i;        //  1-5
  89   char *p2 = p1 + i;        //  2-5
  90   char *p3 = p2 + i;        //  3-5
  91   char *p4 = p3 + i;        //  4-5
  92   char *p5 = p4 + i;        //   5
  93
  94   memset (p5, 0, 5);        // { dg-warning "writing 5 bytes into a region of size" "pr?????" }
  95
  96   sink (p0, p1, p2, p3, p4, p5);
  97 }