static inline union cpu_time_count cpu_time_sub(const clockid_t which_clock,
						union cpu_time_count a,
						union cpu_time_count b)
{
	if (CPUCLOCK_WHICH(which_clock) == CPUCLOCK_SCHED) {
		a.sched -= b.sched;
	}  else {
		a.cpu = cputime_sub(a.cpu, b.cpu);
	}
	return a;
}

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.