The linked PDF doesn't seem to mention anything related specifically to C++. It says that it is possible for bit flips to affect software. They then suggest that Toyota should have used the following practices:

• “Near-perfect” software

• Design out single points of failure

• Justify real time scheduling with analysis

• Watchdog timers that have real “bite”

• Good software architecture

• Good safety culture

This seems like mostly good concrete advice, although I think we can all agree that simply creating "near-perfect software" is a goal, not a solution. If you read up on Toyota's unintended breaking legal issues, it appears that it was most likely driver error, as Toyota did not issue a firmware change to the affected vehicles, and no software problems were ever identified.