gcc/testsuite/c-c++-common/ubsan/ptr-overflow-sanitization-1.c

   1 /* { dg-options "-O -fsanitize=pointer-overflow -fdump-tree-optimized" } */
   2 /* { dg-skip-if "" { *-*-* } "-flto" } */
   3
   4 #define SMAX   __PTRDIFF_MAX__
   5
   6 void foo(void)
   7 {
   8   char *p;
   9   char *p2;
  10   char b[1];
  11   char c[1];
  12
  13   p = b + SMAX; /* pointer overflow check is needed */
  14   p = b;
  15   p++;
  16   p2 = p + 1000;
  17   p2 = p + 999;
  18
  19   p = b + SMAX;
  20   p2 = p + 1; /* pointer overflow check is needed */
  21
  22   p = b;
  23   p--; /* pointer overflow check is needed */
  24   p2 = p + 1;
  25   p2 = p + 2;
  26
  27   p = b - SMAX; /* pointer overflow check is needed */
  28   p2 = p + (SMAX - 2); /* b - 2: no need to check this  */
  29   p2 = p + (SMAX - 1); /* b - 1: no need to check this */
  30   p2 = p + SMAX; /* b: no need to check this */
  31   p2++; /* b + 1 */
  32
  33   p = c;
  34   p++; /* c + 1 */
  35   p = c - SMAX; /* pointer overflow check is needed */
  36   p2 = p + SMAX; /* c: pointer overflow check is needed */
  37   p2++; /* c + 1 */
  38 }
  39
  40 void bar(char *ptr)
  41 {
  42   char *p = ptr - 1000; /* pointer overflow check is needed */
  43   p = ptr + 1000; /* pointer overflow check is needed */
  44   p -= 2000; /* pointer overflow check is needed */
  45 }
  46
  47 void baz(char *ptr)
  48 {
  49   char **p = &ptr;
  50   char **p2 = p + 20; /* pointer overflow check is needed */
  51   p2--;
  52 }
  53
  54 void positive_and_positive (char *ptr)
  55 {
  56   char **p = &ptr;
  57   char **p2 = p + 100; /* pointer overflow check is needed */
  58   p2 = p + 10;
  59   p += 50;
  60 }
  61
  62 void negative_to_positive (char *ptr)
  63 {
  64   char **p = &ptr;
  65   char **p2 = p + 20; /* pointer overflow check is needed */
  66   p2 = p - 10; /* pointer overflow check is needed */
  67   p2 += 15;
  68 }
  69
  70 void negative_to_negative (char *ptr)
  71 {
  72   char **p = &ptr;
  73   char **p2 = p - 20; /* pointer overflow check is needed */
  74   p2 = p - 20;
  75   p2 += 5;
  76 }
  77
  78 /* { dg-final { scan-tree-dump-times "__ubsan_handle_pointer_overflow" 14 "optimized" } } */