extern void abort(void); extern void __assert_fail(const char *, const char *, unsigned int, const char *) __attribute__ ((__nothrow__ , __leaf__)) __attribute__ ((__noreturn__)); void reach_error() { __assert_fail("0", "underapprox_2-1.c", 3, "reach_error"); } void __VERIFIER_assert(int cond) { if (!(cond)) { ERROR: {reach_error();abort();} } return; } int main(void) { unsigned int x = 0; unsigned int y = 1; while (x < 6) { x++; y *= 2; } __VERIFIER_assert(x != 6); }