"Toyota’s developers used MISRA-C and the OSEK operating system, both good choices for a safety-critical real-time system. But then they ignored, sidestepped, or circumvented many of the very safety features they are designed to enforce."

"On a cyclomatic-complexity scale, a rating of 10 is considered workable code, with 15 being the upper limit for some exceptional cases. Toyota’s code had dozens upon dozens of functions that rated higher than 50. Tellingly, the throttle-angle sensor function scored more than 100, making it completely and utterly untestable."

http://www.eejournal.com/archives/articles/20131127-toyota/

Michael Barr was the engineer that was able to sit down with the Toyota engine code during the "unintended acceleration" lawsuit and determine what NASA could not: that the code was a wreck:

http://embeddedgurus.com/barr-code/2013/10/an-update-on-toyo...

Like I said. Bubble gum and duct tape.