5 ms·

Which programming language is commonly used there? Ada, C, C++, JOVIAL, Asm?

by castell 11y ago

lamby 11y ago
With that kind of coding-to-testing-and-documentation ratio, does it even matter?
- tjbiddle 11y ago
  Then to add to it, what are tests written in?
- UnoriginalGuy 11y ago
  Yes. Some languages are better at scoping than others. Functional languages are easier to test because they have more confined scope.
- TheLoneWolfling 11y ago
  Yes, definitely. For a quick example, there are many languages where you cannot accidentally run off the end/start of an array, barring a compiler error. With a language like C / C++, it's possible. Not probable, given that sort of testing. But possible nonetheless. Some languages are also easier to test than others, partially because of this, partially because of other issues. For instance, in some languages you can guarantee at the language level (again, barring compiler errors) that something won't be modified. (Like const, but actually working.)
- gsnedders 11y ago
  Yes. The more the type-system encodes the more the type-checker (in the compiler) proves for you. No matter how much testing you have, nothing will ever come close to proving properties.
shepardrtc 11y ago
Nowadays, its C/C++. In the past it was Ada (at least in the US). Ada was created specifically for this sort of thing (and was actually a requirement for certain projects), but it never gained popularity so companies would just petition the government to use C/C++ instead. Its a shame, too. Ada is fantastic if you want to avoid bugs. I wish more people would give it a chance. On the other hand, I also wonder why people don't think of using Erlang for something like this. The VM is designed for a ridiculous amount of uptime, it has a supervisor tree that can monitor and restart failed processes, and it can interface with C/C++. A rock-solid VM should be running and monitoring life-safety systems.
- tormeh 11y ago
  Using C/C++ on these projects is idiotic. If Airbus used C/C++ then they deserve all the financial loss in the world. They have blood on their hands.
  - lambdaelite 11y ago
    Keep in mind they don't use C/C++. They use C/C++ with a coding standard (like MISRA), static analysis tools, validated compilers, development processes incorporating change control, documentation, verification and validation, etc. What alternative are you suggesting?
    - progman 11y ago
      I know that Ada compilers are 100% verified correct but is there really any validated C++ compiler? Which one? AFAIK (partial) assurance in C/C++ can only be handled by additional testing tools, Frama-C for instance. I agree that C/C++ should not be used for security applications. Ada is a much better choice because it was designed for security.
      - lambdaelite 11y ago
        Not sure if I'm understanding your question correctly, but Wind River claims their Diab compiler is validated by TÜV NORD and is has been used for stuff up to SIL4. In fact, they (http://windriver.com/products/product-overviews/PO_Diab_Compiler_1211.pdf http://windriver.com/products/product-overviews/PO_Diab_Comp...) say: Diab Compiler has been a reliable code generation tool for avionics products certified for DO-178B, products for the nuclear market certified to IEC 60880, railway applications certified to EN 50128, and industrial products certified to IEC 61508, and is now qualified for use in automotive applications certified to ISO 26262. Ada does have some built-in advantages, but I think my point still stands: the language is a small part of the entire SDLC, and I don't think it's the most important part.
        castell 11y ago
deleted 11y ago
[deleted]
jcadam 11y ago
Really, you'd want to use Ada for something like this (The language has survived specifically because it's managed to carve out a niche for itself in aerospace). I once worked on satellite systems using Ada95 and Ada2005 (Ada is definitely not dead). The language is a pain to use but is impressive in that it catches more crap at compile-time than anything else I've seen.
- progman 11y ago
  > Ada is definitely not dead True. More information: http://www.ada2012.org http://www.ada2012.org

Which programming language is commonly used there? Ada, C, C++, JOVIAL, Asm?

by castell 11y ago

Which programming language is commonly used there? Ada, C, C++, JOVIAL, Asm?

lamby 11y ago

With that kind of coding-to-testing-and-documentation ratio, does it even matter?

tjbiddle 11y ago
Then to add to it, what are tests written in?
UnoriginalGuy 11y ago
Yes. Some languages are better at scoping than others. Functional languages are easier to test because they have more confined scope.
TheLoneWolfling 11y ago
Yes, definitely. For a quick example, there are many languages where you cannot accidentally run off the end/start of an array, barring a compiler error. With a language like C / C++, it's possible. Not probable, given that sort of testing. But possible nonetheless. Some languages are also easier to test than others, partially because of this, partially because of other issues. For instance, in some languages you can guarantee at the language level (again, barring compiler errors) that something won't be modified. (Like const, but actually working.)
gsnedders 11y ago
Yes. The more the type-system encodes the more the type-checker (in the compiler) proves for you. No matter how much testing you have, nothing will ever come close to proving properties.

shepardrtc 11y ago

Nowadays, its C/C++. In the past it was Ada (at least in the US). Ada was created specifically for this sort of thing (and was actually a requirement for certain projects), but it never gained popularity so companies would just petition the government to use C/C++ instead. Its a shame, too. Ada is fantastic if you want to avoid bugs. I wish more people would give it a chance. On the other hand, I also wonder why people don't think of using Erlang for something like this. The VM is designed for a ridiculous amount of uptime, it has a supervisor tree that can monitor and restart failed processes, and it can interface with C/C++. A rock-solid VM should be running and monitoring life-safety systems.

tormeh 11y ago
Using C/C++ on these projects is idiotic. If Airbus used C/C++ then they deserve all the financial loss in the world. They have blood on their hands.
- lambdaelite 11y ago
  Keep in mind they don't use C/C++. They use C/C++ with a coding standard (like MISRA), static analysis tools, validated compilers, development processes incorporating change control, documentation, verification and validation, etc. What alternative are you suggesting?
  - progman 11y ago
    I know that Ada compilers are 100% verified correct but is there really any validated C++ compiler? Which one? AFAIK (partial) assurance in C/C++ can only be handled by additional testing tools, Frama-C for instance. I agree that C/C++ should not be used for security applications. Ada is a much better choice because it was designed for security.
    - lambdaelite 11y ago
      Not sure if I'm understanding your question correctly, but Wind River claims their Diab compiler is validated by TÜV NORD and is has been used for stuff up to SIL4. In fact, they (http://windriver.com/products/product-overviews/PO_Diab_Compiler_1211.pdf http://windriver.com/products/product-overviews/PO_Diab_Comp...) say: Diab Compiler has been a reliable code generation tool for avionics products certified for DO-178B, products for the nuclear market certified to IEC 60880, railway applications certified to EN 50128, and industrial products certified to IEC 61508, and is now qualified for use in automotive applications certified to ISO 26262. Ada does have some built-in advantages, but I think my point still stands: the language is a small part of the entire SDLC, and I don't think it's the most important part.
      - castell 11y ago

deleted 11y ago

[deleted]

jcadam 11y ago

Really, you'd want to use Ada for something like this (The language has survived specifically because it's managed to carve out a niche for itself in aerospace). I once worked on satellite systems using Ada95 and Ada2005 (Ada is definitely not dead). The language is a pain to use but is impressive in that it catches more crap at compile-time than anything else I've seen.

progman 11y ago
> Ada is definitely not dead True. More information: http://www.ada2012.org http://www.ada2012.org