Is there any reason to use C instead of C++ for embedded development?

Question

Question

I have two compilers on my hardware C++ and C89

I\'m thinking about using C++ with classes but without polymorphism (to avoid vtables). The main r

Answer 1

No. Any of the C++ language features that could cause problems (runtime polymorphism, RTTI, etc.) can be avoided while doing embedded development. There is a community of embedded C++ developers (I remember reading columns by embedded developers using C++ in the old C/C++ Users' Journal), and I can't imagine they'd be very vocal if the choice was that bad.

Answer 2

Some say that C compilers can generate much more efficient code because they don't have to support the advanced C++ features and can therefore be more aggressive in their optimizations.

Of course, in this case you may want to put the two specific compilers to the test.

Answer 3

C wins on portability - because it is less ambiguous in language spec; therefore offering much better portability and flexibility across different compilers etc (less headaches).

If you aren't going to leverage C++ features to meet a need then go with C.

Answer 4

I have heard that some people prefer C for embedded work due to the fact that is simpler and therefore easier to predict the actual code that will be generated.

I personally would think writing C-style C++ (using templates for type-safety) would give you a lot of advantages though and I can't see any real reason not to.

Answer 5

There are a number of different controller manufacturers around the globe and when you take a look into their designs and the instruction sets that need to be used to configure you may end up in a lot of troubles. The main disadvantage of assembly language is that machine/architecture dependent. It’s really huge ask for a developer to by heart all the instructions set out there to accomplish coding for different controllers. That is why C became more popular in embedded development because C is high-level enough to abstract the algorithms and data structures from hardware-dependent details, making the source code portable across a wide variety of target hardware, architecture independent language and very easy to convert and maintain the code. But we do see some high-level languages (object-oriented) like C, C++, Python, Java etc. are evolving enough to make them under the radar of embedded system development.

Answer 6

I recommend C++ with limitations and notes.

1. Time to market and maintainability. C++ development is easier and faster. So if you are in the designing phase, chose a controller great enough to use C++. (Note, that some high volume market requires as low cost as possible, where you cannot make this choice.)

2. Speed. C can be faster than C++, but be sure this the speed gain is not big. So you can go with C++. Develop your algorithms, test them, and make them faster only if required(!). Use profilers, to point the bottlenecks and rewrite them in extern "C" way, to achieve C speed. (If it still slow implement that part in ASM)

3. Binary size. The C++ codes are bigger, but here is a great answer that tells the details. The size of the compiled binary of a given C code will be the same whether it was compiled using the C or the C++ compiler. "The executable size is hardly related to the language, but to the libraries you include in your project." Go with C++ but avoid advanced functionalities, like streams, string, new, virtual functions, etc. Review all library function before letting them in the final code, because of size limitation (based on this answer)