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As far as I understand all vehicles you mentioned are not subject to DO-178 regulation. If they were then C++ code would have been much less likely be used. It is because C++ code is much more difficult to prove correct either using 100% test case coverege (DO-178B) or thru formal methods (DO-178C). Please correct me if I am wrong, I am doing a research on a similar topic.

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The F-35 (JSF) is DO-178B. The RTOS itself (INTEGRITY) is mostly C and C++.

http://www.militaryaerospace.com/articles/2013/10/software-c...

Well the article says that F-35 runs operating system compliant with DO-178B, right. But it does not say that control logic software (applied software) was a subject to DO-178B certifcation. Anyone can buy a license for DO-178B RTOS, it is not very expensive actually. But to certify your own control avionics algorithms is a whole different story. Agree?

I agree development of the avionics is different from the RTOS. But what makes you say that the avionics algorithms aren't DO-178B? That is something the customer (gov't) would specify to the contractor. I didn't ever work on the JSF avionics code to know the development process. Did you? A lack of press releases about it does not mean it is not DO-178B compliant.

Reading the JSF coding standard, it sounds like all libraries must be DO-178B: "All libraries used must be DO-178B level A certifiable or written in house and developed using the same software development processes required for all other safety-critical software. This includes both the run-time library functions as well as the C/C++ standard library functions. [10,11] Note that we expect certifiable versions of the C++ standard libraries to be available at some point in the future. These certifiable libraries would be allowed under this rule. "

Good point. As far as I know there are no DO-178B complient C++ libraries available yet (STL, for example). If you know any please point out. My reasoning is as follows: While civil avionics must comply with regulatory safety standards, military avionics is not. So economically speaking there is a little sense for them to do such costly certification just to ensure quality.

i can go on all day about this, but this comment has summarised it nicely, you have to understand that to be compliant with DO-178b/c you need to do an un-godly amount of v&v and other things that literally cost millions $ per quarter in a span of a single project, c is much easier to prove right and can easily achieve a good test coverage, c++ on the otherhand is considered a "high level language" and is used for instrument panels and such things, down the stack however you will see people using much more conservative languages.

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