For instance they don't appear to use RAII at all, even in places where it's an obvious win (InterruptLock).
The first advantage for me of C++ everywhere IS RAII.
Do they really not cover it or is the search busted ?
As the maintainer of a C++14 proprietary RTOS, it's probably the most convincing argument to the C guys as to why C++ can benefit embedded codebases. Like not being able to forget to re-drop thread priority when you've temporarily increased it.
Or one of my favorite patterns is returning the object representing the temporary higher priority. If the caller doesn't do anything with the return value, the destructor is called and thread priority reverts to what it was. However, it gives you a chance for the caller to hold on to that high priority object, and get more work done essentially atomically.
In an RTOS of all places, that seems awfully expensive. One generally avoids wasted resources in embedded -- the trade-off is it requires more care during development.
I've never seen RAII work well in an embedded system. Not being able to handle exceptions or errors during destruction ruins everything.
> In an RTOS of all places, that seems awfully expensive. One generally avoids wasted resources in embedded -- the trade-off is it requires more care during development.
The compiler has no issues "optimizing out" the constructor in my experience. The asm looks just like the equivalent C in all of the cases I've seen.
> I've never seen RAII work well in an embedded system. Not being able to handle exceptions or errors during destruction ruins everything.
I mean, we disallow exceptions anyway. And we use RAII for objects where there isn't a weird failure case to be handled like my example of thread priority guards.
> I haven't found many practical guides or tutorials of how to use C++ superiority and boost development process compared to conventional approach of using “C” programming language.
... and does not mention RAII in their quest to write such a guide, they have seriously failed at their goal.