gcc/testsuite/gcc.c-torture/execute/alloca-1.c

   1 /* Verify that alloca storage is sufficiently aligned.  */
   2 /* ??? May fail if BIGGEST_ALIGNMENT > STACK_BOUNDARY.  Which, I guess
   3    can only happen on !STRICT_ALIGNMENT targets.  */
   4
   5 typedef __SIZE_TYPE__ size_t;
   6
   7 struct dummy { int x __attribute__((aligned)); };
   8 #define BIGGEST_ALIGNMENT __alignof__(struct dummy)
   9
  10 _Bool foo(void)
  11 {
  12   char *p = __builtin_alloca(32);
  13   return ((size_t)p & (BIGGEST_ALIGNMENT - 1)) == 0;
  14 }
  15
  16 int main()
  17 {
  18   if (!foo())
  19     abort ();
  20   return 0;
  21 }