tools/build/feature/test-sync-compare-and-swap.c

   1 #include <stdint.h>
   2
   3 volatile uint64_t x;
   4
   5 int main(int argc, char *argv[])
   6 {
   7         uint64_t old, new = argc;
   8
   9         argv = argv;
  10         do {
  11                 old = __sync_val_compare_and_swap(&x, 0, 0);
  12         } while (!__sync_bool_compare_and_swap(&x, old, new));
  13         return old == new;
  14 }