extrano84 already found some errors but also 0 will fail and if x is int (instead of unsigned int) all negative numbers will also fail (but so will the original s-macke obfuscation as well).
Of course you should do the right thing, but if you want to break the private of C++ it is much easier to "#define private public" before including the header file.
The article is not correct on salaries being public:
What is public are your tax reports and those are done a year later. To my knowledge you cannot see all details either, only totals that the tax is based on.
Thus I think your statement is wrong or at least it is not related to the public databases mentioned in the article.
A modern car has >100 ECUs, blink is distributed to a few ECUs, think: front body, rear body, left door, right door plus instrument cluster and maybe a trailer control ECU. It does not look premium if they do not blink in phase so you send CAN command for blinking. (A separate cable introduce cost, weight and faults due to corrosion that are tricky to diagnose, in total you want to avoid that.)
If something disturb CAN or an ECU reboots you would get the described behavior. But it is not obvious (at least not to me) that it must be a software error - could easily be hardware designed with too small margins.
(I have not worked with this issue at Volvo and do not know the actual cause of the problem.)