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

   1 /* PR middle-end/82063 - issues with arguments enabled by -Wall
   2    Verify that alloca() calls in loops are not diagnosed by default.
   3    { dg-do compile }
   4    { dg-require-effective-target alloca }
   5    { dg-options "-O2 -ftrack-macro-expansion=0" } */
   6
   7 extern void* alloca (__SIZE_TYPE__);
   8
   9 void sink (void*);
  10
  11 #define T(x) sink (x)
  12
  13 void test_alloca (unsigned n)
  14 {
  15   /* Verify that alloca(0) is not diagnosed in a loop either.  */
  16   for (unsigned i = 0; i < n; ++i)
  17     T (alloca (0));
  18
  19   /* Verify no warnings for the loops below.  */
  20   for (unsigned i = 0; i < n; ++i)
  21     T (alloca (1));
  22
  23   for (unsigned i = 1; i < n; ++i)
  24     T (alloca (n));
  25 }