19-callback_racing.c

// PARAM:  --set lib.activated[+] sv-comp
extern int __VERIFIER_nondet_int();

#include<pthread.h>
#include "racemacros.h"

void foo(int (*callback)(void)) {
  for (int i = 0; i < 10; i++) {
    if (__VERIFIER_nondet_int())
      callback();
  }
}


int glob;
pthread_mutex_t mutex1 = PTHREAD_MUTEX_INITIALIZER;
pthread_mutex_t mutex2 = PTHREAD_MUTEX_INITIALIZER;


int bar() {
  pthread_mutex_lock(&mutex1);
  access(glob);
  pthread_mutex_unlock(&mutex1);
  return 0;
}

void *t_fun(void *arg) {
  pthread_mutex_lock(&mutex2);
  assert_racefree(glob); // UNKNOWN
  pthread_mutex_unlock(&mutex2);
  return NULL;
}

int main() {
  create_threads(t);
  foo(bar);
  join_threads(t);
  return 0;
}