void abort() { }; extern int __VERIFIER_nondet_int(); /*@ requires ((\old(cond) != 0)) && (cond != 0); ensures ((\old(cond) != 0)) && (1); @*/ void __VERIFIER_assert(int cond) { if (!(cond)) { ERROR: {/*@ assert(0); */;abort();} } return; } int main() { unsigned int x = 0; /*@ loop invariant (((x % 4) == 0)); @*/ while (__VERIFIER_nondet_int()) { x += 4; } __VERIFIER_assert(!(x % 4)); return 0; }