extern void abort(void); void assume_abort_if_not(int cond) { if(!cond) {abort();} } extern int __VERIFIER_nondet_int(void); extern void abort(void); #include void reach_error() { assert(0); } #include #define assume(e) assume_abort_if_not(e) #define assert_nl(e) { if(!(e)) { goto ERROR; } } #undef assert #define assert(e) { if(!(e)) { ERROR: {reach_error();abort();}(void)0; } } int m = 0; void __VERIFIER_atomic_acquire() { assume(m==0); m = 1; } void __VERIFIER_atomic_release() { assume(m==1); m = 0; } void* thr1(void* arg) { int x; int y; x = __VERIFIER_nondet_int(); y = __VERIFIER_nondet_int(); int z; __VERIFIER_atomic_acquire(); if(x == y) { z = 0; } else { z = 1; } if(z == 0) { assert_nl(x == y); } else { assert(x != y); } __VERIFIER_atomic_release(); return 0; } int main() { pthread_t t; while(1) { pthread_create(&t, 0, thr1, 0); } }