Tag Archives: C++11

TDD with Compiler Explorer

Director at Feabhas Limited
Co-Founder and Director of Feabhas since 1995.
Niall has been designing and programming embedded systems for over 30 years. He has worked in different sectors, including aerospace, telecomms, government and banking.
His current interest lie in IoT Security and Agile for Embedded Systems.

Compiler Explorer (CE) has been around for several years now. When it first appeared on the scene, it immediately became an invaluable tool. Its ability to show generated assembler from given source code across many different compilers and ISAs (Instruction Set Architectures) is “mind-blowing”. We use it extensively when teaching as it allows you to clarify the effect your code can have on both performance and memory usage. 

However, rather than limiting itself to only showing generated assembler, recent developments include the […]

Posted in Agile, C/C++ Programming, Testing | Tagged , , , , , , , | Leave a comment

Contract killing (in Modern C++)

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

If you work in high-integrity or safety-critical software then you have a duty-of-care to:

Ensure your code does what it should
Ensure your code doesn’t do what it’s not supposed to.

Moreover, you’re typically required to both demonstrate and document how you’ve achieved this duty-of-care. Typical mechanisms for demonstrating compliance include unit testing and static analysis; documentation usually includes function specifications and test results. The amount of testing, static analysis and documentation you (have to) do depends on the integrity level of your […]

Posted in C/C++ Programming | Tagged , , , , , , , , , , , , , , | 3 Comments

Brace initialization of user-defined types

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

Uniform initialization syntax is one of my favourite features of Modern C++.  I think it’s important, in good quality code, to clearly distinguish between initialization and assignment.

When it comes to user-defined types – structures and classes – brace initialization can throw up a few unexpected issues, and some counter-intuitive results (and errors!).

In this article, I want to have a look at some of the issues with brace initialization of user-defined types – specifically, brace elision and initializer_lists.

Read on for more…

Like (3)

Posted in C/C++ Programming, General | Tagged , , , , , , , | 1 Comment

Your handy cut-out-and-keep guide to std::forward and std::move

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

I love a good ‘quadrant’ diagram.  It brings me immense joy if I can encapsulate some wisdom, guideline or rule-of-thumb in a simple four-quadrant picture.

This time it’s the when-and-where of std::move and std::forward.  In my experience, when programmers are first introduced to move semantics, their biggest struggle is to know when (or when not) to apply std::move or std::forward.  Usually, it’s a case of “keep apply std::move until it compiles”.  I’ve been there myself.

To that end I’ve put together a […]

Posted in C/C++ Programming | Tagged , , , , , , , | 2 Comments

“May Not Meet Developer Expectations” #77

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

Question:  Does the following compile?

int func()
{
  int (func);
  return

Posted in C/C++ Programming | Tagged , , , , , | 3 Comments

Exceptional fun!

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

In this article I want to look at some applications for one of C++’s more obscure mechanisms, the function

Posted in C/C++ Programming | Tagged , , , , , , | 3 Comments

Making things do stuff – Part 9

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

As a final instalment in this series on hardware manipulation I thought I’d revisit read-only and write-only register types.

Using tag dispatch is not the only way to solve the read- or write-only Register problem.  For completeness let’s explore two other alternatives – SFINAE and constexpr if.

For these examples I’m going to use a simplified version of our Register class.  I’m ignoring the bit proxy class and using a reduced API.  Once understood, the techniques below can be applied to these […]

Posted in C/C++ Programming, Design Issues | Tagged , , , , , , , , , , | 1 Comment

Making things do stuff – Part 7

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

In our previous article we explored using templates to build a generic ‘register’ type to allow programmers to access hardware without all the nasty syntax of integer-to-pointer casting, etc.

At the moment, this class gives us little extra functionality beyond cleaning up the syntax (although, in its favour, it also doesn’t incur any additional run-time cost/performance).

In this article we’re going to extend our design to consider special hardware register types – notably read-only and write-only registers – and see how we can […]

Posted in C/C++ Programming | Tagged , , , , , , | 2 Comments

Making things do stuff – Part 6

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

As code designers we tend to eschew specific ‘stove-pipe’ code in favour of reusable code elements.  Up until now we’ve been coding some very specific examples so it’s probably worth looking at some more generic solutions.

In this article we’ll look at building generic register manipulation classes (or, as one commenter referred to them, ‘register proxy’ classes).  Here, we’re really exploring code design rather than coding ‘mechanics’.  I’m using this to explore some factors like the balance between efficiency, performance and […]

Posted in C/C++ Programming | Tagged , , , , , , , | 3 Comments

Death and (virtual) destruction*

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.
Glennan Carnie

This time, we’ll have a more detailed look at one of those everybody-knows-that elements of C++ – virtual destructors.

More specifically, I want to reinforce under what circumstances you should make your destructor virtual; and when you don’t need to (despite what your compiler might say)

(*there’s no

Posted in C/C++ Programming, Design Issues | Tagged , , , , , , , , | 9 Comments