source: CIVL/examples/pthread/cprover/02_inc_cas_true.c@ 1aaefd4

//http://www.ibm.com/developerworks/java/library/j-jtp04186/index.html
//Listing 2. A nonblocking counter using CAS

#include <pthread.h>

#define assert(e) { if(!(e)) { ERROR: goto ERROR; (void)0; } }

void __VERIFIER_atomic_CAS(
  volatile unsigned *v,
  unsigned e,
  unsigned u,
  unsigned *r)
{
        if(*v == e)
        {
                *v = u, *r = 1;
        }
        else
        {
                *r = 0;
        }
}

volatile unsigned value;

void* thr1(void* arg) {
        unsigned v,vn,casret;

        do {
                v = value;

                if(v == 0u-1) {
                        return 0;
                }

                vn = v + 1;

                __VERIFIER_atomic_CAS(&value,v,vn,&casret);
        }
        while (casret==0);
        assert(value > v);

        return 0;
}

int main(){
  pthread_t t;

        while(1) { pthread_create(&t, 0, thr1, 0); }
}