I stand corrected. However, in the thread you link you it's pointed out that ZCash has no auditing built in, so it's not possible to actually see how many coins

I stand corrected. However, in the thread you link you it's pointed out that ZCash has no auditing built in, so it's not possible to actually see how many coins are in circulation. So saying ZCash hasn't suffered from a bug of this nature would be presumptuous, although it may be perfectly correct.