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C++, Ada, ...

Started by pozz April 17, 2021
What do you think about different languages than usual C for embedded 
systems?

I mean C++, Ada but also Python. Always more powerful embedded 
processors are coming, so I expect new and modern languages will enter 
in the embedded world.

Hardware are cheaper and more powerful than ever, but software stays 
expensive. New and modern languages could reduce the software cost, 
because they are simpler than C and much more similar to desktop/server 
programming paradigm.

We embedded sw developers were lucky: electronics and technologies 
change rapidly, but sw for embedded has changed slower than 
desktop/mobile sw. Think of mobile app developers: maybe they already 
changed IDEs, tools and languages ten times in a few years.
C language for embedded is today very similar than 10 years ago.

However I think this situation for embedded developers will change in 
the very next years. And we will be forced to learn modern technologies, 
such as new languages and tools.
Is it ok for me to study and learn new things... but it will be more 
difficult to acquire new skills for real jobs.

What do you think?
On 17/04/2021 17:48, pozz wrote:
> What do you think about different languages than usual C for embedded > systems? > > I mean C++, Ada but also Python. Always more powerful embedded > processors are coming, so I expect new and modern languages will enter > in the embedded world. > > Hardware are cheaper and more powerful than ever, but software stays > expensive. New and modern languages could reduce the software cost, > because they are simpler than C and much more similar to desktop/server > programming paradigm. > > We embedded sw developers were lucky: electronics and technologies > change rapidly, but sw for embedded has changed slower than > desktop/mobile sw. Think of mobile app developers: maybe they already > changed IDEs, tools and languages ten times in a few years. > C language for embedded is today very similar than 10 years ago. > > However I think this situation for embedded developers will change in > the very next years. And we will be forced to learn modern technologies, > such as new languages and tools. > Is it ok for me to study and learn new things... but it will be more > difficult to acquire new skills for real jobs. > > What do you think?
You should probably add Rust to your list - I think its popularity will increase. Python is great when you have the resources. It's the language I use most on PC's and servers, and it is very common on embedded Linux systems (like Pi's, and industrial equivalents). Micropython is sometimes found on smaller systems, such as ESP32 devices. Ada involves a fair amount of change to how you work, compared to C development. (Disclaimer - I have only done a very small amount of Ada coding, and no serious projects. But I have considered it as an option.) I really don't see it becoming much more common, and outside of niche areas (defence, aerospace) it is very rare. Programming in Ada often takes a lot more effort even for simple things, leading quickly to code that is so wordy that it is unclear what is going on. And most of the advantages of Ada (such as better typing) can be achieved in C++ with less effort, and at the same time C++ can give additional safety on resources that is harder to get on Ada. (But Ada has some nice features introspective that C++ programmers currently only dream about.) C++ is not uncommon in embedded systems, and I expect to see more of it. I use it as my main embedded language now. C++ gives more scope for getting things wrong in weird ways, and more scope for accidentally making your binary massively larger than you expect, but with care it makes it a lot easier to write clear code and safe code, where common C mistakes either can't happen or you get compile-time failures. It used to be the case that C++ compilers were expensive and poor quality, that the resulting code was very slow on common microcontrollers, and that the language didn't have much extra to offer small-systems embedded developers. That, I think, has changed in all aspects. I use gcc 10 with C++17 on Cortex-M devices, and features like templates, strong enumerations, std::array, and controlled automatic conversions make it easier to write good code.
On 17/04/21 17:45, David Brown wrote:
> And most of > the advantages of Ada (such as better typing) can be achieved in C++ > with less effort, and at the same time C++ can give additional safety on > resources that is harder to get on Ada.
Interesting. Could you give a quick outline of that?
On 18/4/21 2:45 am, David Brown wrote:
> On 17/04/2021 17:48, pozz wrote: >> What do you think about different languages than usual C for embedded >> systems? >> >> I mean C++, Ada but also Python. Always more powerful embedded >> processors are coming, so I expect new and modern languages will enter >> in the embedded world. >> >> Hardware are cheaper and more powerful than ever, but software stays >> expensive. New and modern languages could reduce the software cost, >> because they are simpler than C and much more similar to desktop/server >> programming paradigm. >> >> We embedded sw developers were lucky: electronics and technologies >> change rapidly, but sw for embedded has changed slower than >> desktop/mobile sw. Think of mobile app developers: maybe they already >> changed IDEs, tools and languages ten times in a few years. >> C language for embedded is today very similar than 10 years ago. >> >> However I think this situation for embedded developers will change in >> the very next years. And we will be forced to learn modern technologies, >> such as new languages and tools. >> Is it ok for me to study and learn new things... but it will be more >> difficult to acquire new skills for real jobs. >> >> What do you think? > > You should probably add Rust to your list - I think its popularity will > increase.
+1. I've used C++ for over 30 years, but Rust is going to rule. It's not really any harder, but vastly safer, especially for parallel coding. CH
On 4/17/2021 11:48 AM, pozz wrote:
> What do you think about different languages than usual C for embedded > systems? > > I mean C++, Ada but also Python. Always more powerful embedded > processors are coming, so I expect new and modern languages will enter > in the embedded world.
Another +1 for C++. We started using C++ for embedded ~25 years ago, and the tool quality (and language) is vastly better now. Main problem using C++ is lack of available qualified staff - too many still only trained in C. C++, even more than C, *requires* painful amount of knowledge of how things work under the hood to use safely, not a good quality for any tool in any realm. But for *qualified* developers, C++ certainly gives faster development, produces better (ie faster/smaller) code, and generally improves life (compared to C).
On 4/17/2021 6:07 PM, Dave Nadler wrote:

> Another +1 for C++. We started using C++ for embedded ~25 years ago, and the > tool quality (and language) is vastly better now. Main problem using C++ is > lack of available qualified staff - too many still only trained in C. C++, even > more than C, *requires* painful amount of knowledge of how things work under > the hood to use safely, not a good quality for any tool in any realm. But for > *qualified* developers, C++ certainly gives faster development, produces better > (ie faster/smaller) code, and generally improves life (compared to C).
This is exactly why I *don't* use C++ (or any "new fangled" languages) for product development. I'm often the "Rev 1" author of a product. Then, move on (to another product, another client, another application domain). I'm contractually obligated to fix bugs in my code (indefinitely and at no charge) -- it's one of my selling points ("Yes, I'm *that* confident in the code I've created for you!") The last thing I need is some coder-wannabe tweeking my code with some "harmless" change... then, defiantly claiming (to his management) that the newly broken code is a consequence of my initial design (he's just UNCOVERED a bug). So, I get called back to *teach* the dweeb why what he's done won't work. And, in the process, inevitably have to show him how to do what he wants to do. Yeah, I can bill the client -- which is countered with "but you said you'd support your code, for free?" (yeah, but that wasn't MY code!). Regardless, I'm not keen on spending my time as a tutor! Or, swallow it as cost of doing business. It's considerably easier to find multiple C coders (and hope one of them will catch the guy's mistake) than a qualified C++, Erlang, Python, etc. coder -- esp when you're dealing with small firms. So, my strategy becomes: "Have you rebuilt MY sources using the tools that *I* used? Does the product exhibit this bug? If not, it's not my problem!" [I can do this even with some other language. But, the dweeb will inevitably claim -- to the owner/management -- that his changes are benign. They, of course, won't want to think they hired an inept employee, so...]
On 2021-04-17 19:45, David Brown wrote:
> On 17/04/2021 17:48, pozz wrote: >> What do you think about different languages than usual C for embedded >> systems? >> >> I mean C++, Ada but also Python. Always more powerful embedded >> processors are coming, so I expect new and modern languages will enter >> in the embedded world. >> >> ... >> Is it ok for me to study and learn new things... but it will be more >> difficult to acquire new skills for real jobs. >> >> What do you think? > > ... > Ada involves a fair amount of change to how you work, compared to C > development. (Disclaimer - I have only done a very small amount of Ada > coding, and no serious projects. But I have considered it as an > option.) I really don't see it becoming much more common, and outside > of niche areas (defence, aerospace) it is very rare. Programming in Ada > often takes a lot more effort even for simple things, leading quickly to > code that is so wordy that it is unclear what is going on.
That depends, I guess, on what one considers "simple", and also, of course, on how familiar one is with the languages. Perhaps it is time to link once again to the experience of C versus Ada in an introductory embedded-programming class using a model rail-road example, where the students using Ada fared much better than those using C: http://archive.adaic.com/projects/atwork/trains.html I am (as you guessed) an Ada fan, and find it a pleasure to write, even if it takes more keystrokes than the equivalent in C. For embedded systems in particular, I find portability to be a great advantage of Ada. With few exceptions, the embedded program can be exercised on the development host, and if the target supports the standard Ada tasking system (or a subset of it), this applies even to multi-threaded programs (without the need to emulate some embedded RTK/OS on the host).
> And most of the advantages of Ada (such as better typing) can be > achieved in C++ with less effort,
According to the link above, the main Ada advantage was the ability to define one's own problem-oriented scalar types, such as integers with specific value ranges. AIUI, this is not easily done in C++.
> and at the same time C++ can give additional safety on > resources that is harder to get on Ada. (But Ada has some nice features > introspective that C++ programmers currently only dream about.)
Can you be more specific on those points, please?
> It used to be the case that C++ compilers were expensive and poor > quality, that the resulting code was very slow on common > microcontrollers, and that the language didn't have much extra to offer > small-systems embedded developers. That, I think, has changed in all > aspects. I use gcc 10 with C++17 on Cortex-M devices, and features like > templates, strong enumerations, std::array, and controlled automatic > conversions make it easier to write good code.
AdaCore provides the gcc-based GNAT Ada compiler for several embedded targets, free to use for open-source projects: libre.adacore.com. Commercial projects can use Ada on other targets by means of the (different) AdaCore compiler that generates C code as an intermediate representation.
On 18/04/21 02:07, Dave Nadler wrote:
> Main problem using C++ is lack of available qualified staff - too many still > only trained in C. C++, even more than C, *requires* painful amount of knowledge > of how things work under the hood to use safely, not a good quality for any tool > in any realm.
Yes indeed. Especially when coupled with inexperience leading someone to believe they understand C or C++. Your other (valid) caveats and points snipped for brevity.
On 17/04/2021 20:55, Tom Gardner wrote:
> On 17/04/21 17:45, David Brown wrote: >> And most of >> the advantages of Ada (such as better typing) can be achieved in C++ >> with less effort, and at the same time C++ can give additional safety on >> resources that is harder to get on Ada.  > > Interesting. Could you give a quick outline of that? >
Which part? My understanding of Ada classes is that, like Pascal classes, you need to explicitly construct and destruct objects. This gives far greater scope for programmers to get things wrong than when they are handled automatically by the language. On the other hand, some of Ada's type mechanisms make it a lot easier to make new types with similar properties while remaining distinct (such as subranges of integer types). You can do that in C++, but someone needs to make the effort to make the appropriate class templates. Thus these are more often used in Ada coding than in C++ coding. On the third hand (three hands are always useful for programming), the wordy nature of type conversions in Ada mean programmers would be tempted to take shortcuts and skip these extra types.
Un bel giorno pozz digitò:

> What do you think about different languages than usual C for embedded > systems? > > I mean C++, Ada but also Python. Always more powerful embedded > processors are coming, so I expect new and modern languages will enter > in the embedded world.
I wouldn't include C++ in the list of "modern languages". One might as well use C. As for the "more modern" languages (Python, C#, Java etc) I've used most of them and maybe it's the old man in me speaking, but I haven't felt any inherent important advantages in using them. Their success is mostly due to better support by popular development tools. These days, smarter people praise functional programming languages (Haskell, Clojure, etc...). They promise tangible advantages compared to imperative languages, especially for maintainability and reliability. But I think that even if they will gain popularity, years would pass before you will see real applications in the embedded world. Python is a "hybrid", it can be also used as a functional programming language, and it will probably gain popularity in embedded systems. -- Fletto i muscoli e sono nel vuoto.