gcc/testsuite/gcc.dg/Wstringop-overflow-15.c

   1 /* PR middle-end/91458 - inconsistent warning for writing past the end
   2    of an array member
   3    Verify that the -Wstringop-overflow detection doesn't cause an ICE
   4    for either kind of VLAs (member and non-member).
   5    Diagnosing the accesses is the subject of pr82608.
   6    { dg-do compile }
   7    { dg-options "-O2 -Wall -Wno-array-bounds" }
   8    { dg-require-effective-target alloca } */
   9
  10 void sink (void*);
  11
  12 void vla_unbounded (int n)
  13 {
  14   char a[n];
  15
  16   a[0] = 0;
  17   a[1] = 1;
  18   a[n] = n;         // { dg-warning "\\\[-Wstringop-overflow" "pr82608" { xfail *-*-* } }
  19
  20   sink (&a);
  21 }
  22
  23 void vla_bounded (int n)
  24 {
  25   if (n > 32)
  26     n = 32;
  27
  28   char a[n];
  29
  30   a[0] = 0;
  31   a[1] = 1;
  32   a[31] = 31;
  33
  34   sink (&a);
  35
  36   a[n] = n;         // { dg-warning "\\\[-Wstringop-overflow" "pr82608" { xfail *-*-* } }
  37   a[32] = 32;       // { dg-warning "\\\[-Wstringop-overflow" "pr82608" }
  38   a[69] = 69;       // { dg-warning "\\\[-Wstringop-overflow" "pr82608" }
  39
  40   sink (&a);
  41 }
  42
  43
  44 void member_vla_unbounded (int n)
  45 {
  46   struct S { char i, a[n]; } s;
  47
  48   s.a[0] = 0;
  49   s.a[1] = 1;
  50   s.a[n] = n;       // { dg-warning "\\\[-Wstringop-overflow" "pr82608" { xfail *-*-* } }
  51
  52   sink (&s);
  53 }
  54
  55 void member_vla_bounded (int n)
  56 {
  57   if (n > 32)
  58     n = 32;
  59
  60   struct S { char i, a[n]; } s;
  61
  62   s.a[0] = 0;
  63   s.a[1] = 1;
  64   s.a[31] = 31;
  65
  66   sink (&s);
  67
  68   s.a[n] = n;       // { dg-warning "\\\[-Wstringop-overflow" "pr82608" { xfail *-*-* } }
  69   s.a[32] = 32;     // { dg-warning "\\\[-Wstringop-overflow" "pr82608" }
  70   s.a[69] = 69;     // { dg-warning "\\\[-Wstringop-overflow" "pr82608" }
  71
  72   sink (&s);
  73 }