int __unbuffered_cnt=0; int __unbuffered_p0_r1=0; int __unbuffered_p0_r3=0; int __unbuffered_p1_r1=0; int __unbuffered_p1_r3=0; int __unbuffered_p2_r1=0; int __unbuffered_p2_r3=0; int x=0; int y=0; int z=0; void * P0(void * arg) { __unbuffered_p0_r1 = 2; z = __unbuffered_p0_r1; __unbuffered_p0_r3 = 1; x = __unbuffered_p0_r3; // Instrumentation for CPROVER __unbuffered_cnt++; } void * P1(void * arg) { __unbuffered_p1_r1 = 2; x = __unbuffered_p1_r1; __unbuffered_p1_r3 = y; // Instrumentation for CPROVER __unbuffered_cnt++; } void * P2(void * arg) { __unbuffered_p2_r1 = 1; y = __unbuffered_p2_r1; __unbuffered_p2_r3 = 1; z = __unbuffered_p2_r3; // Instrumentation for CPROVER __unbuffered_cnt++; } int main() { __CPROVER_ASYNC_0: P0(0); __CPROVER_ASYNC_1: P1(0); __CPROVER_ASYNC_2: P2(0); __CPROVER_assume(__unbuffered_cnt==3); __CPROVER_assert(!(x==2 && z==2 && __unbuffered_p1_r3==0), "Program proven to be relaxed for PPC, model checker says YES."); return 0; }