source: CIVL/examples/translation/pthread/cprover/01_inc_true.c@ 63d4ef2

//http://www.ibm.com/developerworks/java/library/j-jtp04186/index.html
//A counter using locks

#include <pthread.h>

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

volatile unsigned value, m = 0;

void __VERIFIER_assume(int expression) { if (!expression) { LOOP: goto LOOP; }; return; }

void __VERIFIER_atomic_acquire()
{
        assume(m==0);
        m = 1;
}

void __VERIFIER_atomic_release()
{
        assume(m==1);
        m = 0;
}

void * thr1(void* arg) {
        unsigned v = 0;

        __VERIFIER_atomic_acquire();
        if(value == 0u-1) {
                __VERIFIER_atomic_release();

                return 0;
        }else{

                v = value;
                value = v + 1;
                __VERIFIER_atomic_release();

                assert(value > v);

                return 0;
        }
}

int main(){
  pthread_t t;

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