It has been over 40 years that automobiles and C++ have co-existed. While the world is well aware of the features of the cars that run on the roads, not many are familiar with the fact that C++ is the reason why today cars are more efficient, safe, smart, and clean. The trend of convergence of these two disciplines has made it almost impossible to have one without the other.

To achieve good interoperability between software components is the necessity for good abstractions, interface contracts, and deterministic functioning. C++ language is positioning itself as a key factor in bringing all the mentioned points together with its flexibility, OOP facilities, and a good typing system. In addition to that, there is a substantial talent pool, an established set of performant containers and algorithms, and a very advanced toolchain (compilers, static code analysis tools, testing frameworks, etc.). All these are supported by language features like RAII, smart pointers, lambdas, templates, concepts, contracts, and many others. Furthermore, even though being a high-level language, it provides low-level system programming capabilities and therefore turns out to be an ideal language for the development of cyber-physical systems.

The C++ language provides a comprehensive feature set for handling lifetime and ownership of memory in a very robust and safe way making it an ideal candidate for applications where there is no scope of overlooking the overhead of passing the data around or making redundant copies of big data structures. There is no garbage collector in C++ like in some other managed languages where the entire system randomly comes to a complete halt on a
non-deterministic basis so that GC can mop up the unused resources.

The final point being dependability is the one being most discussed in autonomous driving. In its formal definition, dependability refers to reliability, availability, safety, security, maintainability, and all the accompanying activities necessary to reach that. Informally, in terms of AD development, it boils down to two major requirements: “keep running whenever needed” and “do not run into things”. While software in other tech areas is developed with positive scenarios in mind, AD development is failure driven – the possibilities of failure are addressed from the beginning, and mechanisms to validate failure handling are assured. That kind of development mindset is a must overall levels of development, involving both high- and low-level software.

To do autonomous driving software one needs to make it safe, to make it safe one is to be able to validate and vouch for all of it. Reflecting on the statements from the language creator Bjarne Stroustrup that in C++ one pays only for what one uses and that the concept of C++ language is to have a simple and direct mapping for hardware means that there is a natural progression into critical and high scale applications like autonomous driving. Such a concept allows a good overview of function chain components and the possibility of validation of every one of them.

Considering the huge scale of autonomous driving software, even though you do the entire code correctly and vouch for all of it, what guarantees you is that in the end when you compile it, the compiler you are using is producing the desired machine instructions for the target architecture. C++ history and maturity make it an ideal candidate for such applications considering the availability of proven and qualified compilers and tools supporting the entire C++ software development ecosystem.