gcc/testsuite/gcc.dg/Wstringop-overflow-79.c

   1 /* Verify that a separate note is issued for each offset into the same
   2    object after a -Wstringop-overflow.  Since all arguments are known
   3    the test doesn't need optimization.  Wstringop-overflow-79.c verifies
   4    they're also issued at -O2.
   5    { dg-do compile }
   6    { dg-options "-O0 -Wno-array-bounds" } */
   7
   8 extern char a[8];                 // { dg-message "at offset \\\[3, 6] into destination object 'a'" "note 1" }
   9                                   // { dg-message "at offset \\\[5, 8] into destination object 'a'" "note 2" { target *-*-* } .-1 }
  10
  11 void test_2_notes (int i)
  12 {
  13   char *p = i ? a + 3 : a + 5;
  14   __builtin_memset (p, 0, 7);     // { dg-warning "-Wstringop-overflow" }
  15 }
  16
  17
  18 extern char b[8];                 // { dg-message "at offset \\\[3, 6] into destination object 'b'" "note 1" }
  19                                   // { dg-message "at offset \\\[4, 7] into destination object 'b'" "note 2" { target *-*-* } .-1 }
  20                                   // { dg-message "at offset \\\[5, 8] into destination object 'b'" "note 3" { target *-*-* } .-2 }
  21
  22 void test_3_notes (int i)
  23 {
  24   char *p = i < 0 ? b + 3 : 0 < i ? b + 5 : b + 4;
  25   __builtin_memset (p, 0, 7);     // { dg-warning "-Wstringop-overflow" }
  26 }
  27
  28
  29 extern char c[8];                 // { dg-message "at offset \\\[3, 6] into destination object 'c'" "note 1" }
  30                                   // { dg-message "at offset \\\[4, 7] into destination object 'c'" "note 2" { target *-*-* } .-1 }
  31                                   // { dg-message "at offset \\\[5, 8] into destination object 'c'" "note 3" { target *-*-* } .-2 }
  32                                   // { dg-message "at offset \\\[6, 8] into destination object 'c'" "note 4" { target *-*-* } .-3 }
  33
  34 void test_4_notes (int i)
  35 {
  36   char *p;
  37   if (i < -1)
  38     p = c + 3;
  39   else if (i < 0)
  40     p = c + 4;
  41   else if (0 < i)
  42     p = c + 6;
  43   else
  44     p = c + 5;
  45
  46   __builtin_memset (p, 0, 7);     // { dg-warning "-Wstringop-overflow" }
  47 }
  48
  49
  50 extern char d[8];                 // { dg-message "at offset \\\[3, 6] into destination object 'd'" "note 1" }
  51                                   // { dg-message "at offset \\\[4, 7] into destination object 'd'" "note 2" { target *-*-* } .-1 }
  52                                   // { dg-message "at offset \\\[5, 8] into destination object 'd'" "note 3" { target *-*-* } .-2 }
  53                                   // { dg-message "at offset \\\[6, 8] into destination object 'd'" "note 4" { target *-*-* } .-3 }
  54                                   // { dg-message "at offset \\\[7, 8] into destination object 'd'" "note 5" { target *-*-* } .-4 }
  55
  56 void test_5_notes (int i)
  57 {
  58   char *p;
  59   switch (i)
  60     {
  61     case -9: p = d + 3; break;
  62     case -5: p = d + 4; break;
  63     case  0: p = d + 5; break;
  64     case  3: p = d + 6; break;
  65     case  4: p = d + 7; break;
  66     default: return;
  67     }
  68
  69   __builtin_memset (p, 0, 7);     // { dg-warning "-Wstringop-overflow" }
  70 }