gcc/testsuite/gcc.dg/Wvla-larger-than-2.c

   1 /* { dg-do compile } */
   2 /* { dg-require-effective-target stdint_types } */
   3 /* { dg-require-effective-target alloca } */
   4 /* { dg-options "-O2 -Wvla-larger-than=40" } */
   5
   6 #include <stdint.h>
   7
   8 void f0 (void *);
   9 void
  10 f1 (__SIZE_TYPE__ a)
  11 {
  12   if (a <= 10)
  13     {
  14       // 10 * 4 bytes = 40: OK!
  15       uint32_t x[a];
  16       f0 (x);
  17     }
  18 }
  19
  20 void
  21 f2 (__SIZE_TYPE__ a)
  22 {
  23   if (a <= 11)
  24     {
  25       // 11 * 4 bytes = 44: Not OK.
  26       uint32_t x[a]; // { dg-warning "array may be too large" }
  27       // { dg-message "note:.*argument may be as large as 44" "note" { target *-*-* } .-1 }
  28       f0 (x);
  29     }
  30 }
  31
  32 void
  33 f3 (__SIZE_TYPE__ a, __SIZE_TYPE__ b)
  34 {
  35   if (a <= 5 && b <= 3)
  36     {
  37       // 5 * 3 * 4 bytes = 60: Not OK.
  38       uint32_t x[a][b]; // { dg-warning "array may be too large" }
  39       f0 (x);
  40     }
  41 }
  42
  43 void
  44 f4 (__SIZE_TYPE__ a, __SIZE_TYPE__ b)
  45 {
  46   if (a <= 5 && b <= 2)
  47     {
  48       // 5 * 2 * 4 bytes = 40 bytes: OK!
  49       uint32_t x[a][b];
  50       f0 (x);
  51     }
  52 }
  53
  54 void
  55 f5 (__SIZE_TYPE__ len)
  56 {
  57   // Test that a direct call to __builtin_alloca_with_align is not
  58   // confused with a VLA.
  59   void *p = __builtin_alloca_with_align (len, 8);
  60   f0 (p);
  61 }
  62
  63 void
  64 f6 (unsigned stuff)
  65 {
  66   int n = 7000;
  67   do {
  68     char a[n]; // { dg-warning "variable-length array is too large" }
  69     f0 (a);
  70   } while (stuff--);
  71 }