AdaCore Blog

47 entries tagged with #GitHub

by Fabien Chouteau, Emma Adby, Yannick Moy is here

We are very proud to announce the availability of our new Ada and SPARK learning platform, which will replace AdaCoreU(niversity) e-learning platform. Learn all about it in this blog post.

#Teaching    #Ada    #SPARK   

by Yannick Moy

Security Agency Uses SPARK for Secure USB Key

​ANSSI, the French national security agency, has published the results of their work since 2014 on designing and implementing an open-hardware & open-source USB key that provides defense-in-depth against vulnerabilities on the USB hardware, architecture, protocol and software stack. In this project called WooKey, Ada and SPARK are key components for the security of the platform. This is a very compelling demontration of both the usability and the power of safe languages and formal verification to develop secure systems.

#SPARK    #Security    #Formal Methods   

by Johannes Kanig

Taking on a Challenge in SPARK

Last week, the programmer Hillel posted a challenge (the link points to a partial postmortem of the provided solutions) on Twitter for someone to prove a correct implementation of three small programming problems: Leftpad, Unique, and Fulcrum.

#Formal Verification    #Formal Methods    #SPARK   

by Thomas Quinot

PolyORB now lives on Github

PolyORB, AdaCore's versatile distribution middleware, now lives on Github. Its new home is

by Rob Tice

SPARKZumo Part 2: Integrating the Arduino Build Environment Into GPS

This is part #2 of the SPARKZumo series of blog posts. This post covers the build system that was used to build the SPARKZumo project and how to automate the process in GPS.

#GPS    #Python    #Libadalang    #Arduino    #CCG   

by Rob Tice

SPARKZumo Part 1: Ada and SPARK on Any Platform

So you want to use SPARK for your next microcontroller project? Great choice! All you need is an Ada 2012 ready compiler and the SPARK tools. But what happens when an Ada 2012 compiler isn’t available for your architecture?

#CCG    #SPARK    #Arduino    #RISC V    #embedded   

by Fabien Chouteau

Ada on the micro:bit

Updated July 2018

#embedded    #Ada    #nRF51    #ARM   

by Yannick Moy

Tokeneer Fully Verified with SPARK 2014

Tokeneer is a software for controlling physical access to a secure enclave by means of a fingerprint sensor. This software was created by Altran (Praxis at the time) in 2003 using the previous generation of SPARK language and tools, as part of a project commissioned by the NSA to investigate the rigorous development of critical software using formal methods. The project artefacts, including the source code, were released as open source in 2008. Tokeneer was widely recognized as a milestone in industrial formal verification. We recently transitioned this software to SPARK 2014, and it allowed us to go beyond what was possible with the previous SPARK technology. We have also shown how security vulnerabilities introduced in the code can be detected by formal verification.

#SPARK    #Formal Methods   

by Johannes Kanig

Bitcoin blockchain in Ada: Lady Ada meets Satoshi Nakamoto

Bitcoin is getting a lot of press recently, but let's be honest, that's mostly because a single bitcoin worth 800 USD in January 2017 was worth almost 20,000 USD in December 2017. However, bitcoin and its underlying blockchain are beautiful technologies that are worth a closer look. Let’s take that look with our Ada hat on!

#Bitcoin    #Blockchain    #Ada   

by Felix Krause

The Road to a Thick OpenGL Binding for Ada: Part 1

This blog post is part one of a tutorial based on the OpenGLAda project and will cover some the background of the OpenGL API and the basic steps involved in importing platform-dependent C functions.

#OpenGL    #Binding   

by Lionel Matias

Leveraging Ada Run-Time Checks with Fuzz Testing in AFL

Fuzzing is a very popular bug finding method. The concept, very simple, is to continuously inject random (garbage) data as input of a software component, and wait for it to crash. If, like me, you find writing robustness test tedious and not very efficient in finding bugs, you might want to try fuzzing your Ada code. Here's a recipe to fuzz-test your Ada code, using American Fuzzy Lop and all the runtime checks your favorite Ada compiler can provide. Let's see (quickly) how AFL works, then jump right into fuzzing 3 open-source Ada libraries: ZipAda, AdaYaml, and GNATCOLL.JSON.

#Testing    #Ada    #VerificationTools   

by Pierre-Marie de Rodat, Raphaël Amiard

Cross-referencing Ada with Libadalang

Libadalang has come a long way since the last time we blogged about it. In the past 6 months, we have been working tirelessly on name resolution, a pretty complicated topic in Ada, and it is finally ready enough that we feel ready to blog about it, and encourage people to try it out.

#Libadalang    #Ada   

by J. German Rivera

Make with Ada 2017- A "Swiss Army Knife" Watch

Summary  The Hexiwear is an IoT wearable development board that has two NXP Kinetis microcontrollers. One is a K64F (Cortex-M4 core) for running the main embedded application software. The other one is a KW40 (Cortex M0+ core) for running a wireless connectivity stack (e.g., Bluetooth BLE or Thread). The Hexiwear board also has a rich set of peripherals, including OLED display, accelerometer, magnetometer, gryroscope, pressure sensor, temperature sensor and heart-rate sensor. This blog article describes the development of a "Swiss Army Knife" watch on the Hexiwear platform. It is a bare-metal embedded application developed 100% in Ada 2012, from the lowest level device drivers all the way up to the application-specific code, for the Hexiwear's K64F microcontroller. I developed Ada drivers for Hexiwear-specific peripherals from scratch, as they were not supported by AdaCore's Ada drivers library. Also, since I wanted to use the GNAT GPL 2017 Ada compiler but the GNAT GPL distribution did not include a port of the Ada Runtime for the Hexiwear board, I also had to port the GNAT GPL 2017 Ada runtime to the Hexiwear. All this application-independent code can be leveraged by anyone interested in developing Ada applications for the Hexiwear wearable device.

by Jonas Attertun

Make with Ada 2017: Brushless DC Motor Controller

This project involves the design of a software platform that provides a good basis when developing motor controllers for brushless DC motors (BLDC/PMSM). It consist of a basic but clean and readable implementation of a sensored field oriented control algorithm. Included is a logging feature that will simplify development and allows users to visualize what is happening. The project shows that Ada successfully can be used for a bare-metal project that requires fast execution.

#Makers    #MakewithAda    #STM32    #embedded   

by Yannick Moy

Prove in the Cloud

We have put together a byte (8 bits) of examples of SPARK code on a server in the cloud. The benefit with this webpage is that anyone can now experiment live with SPARK without installing first the toolset. Something particularly interesting for academics is that all the code for this widget is open source. So you can setup your own proof server for hands-on sessions, with your own exercises, in a matter of minutes.


by Pierre-Marie de Rodat

Highlighting Ada with Libadalang

While we are working very hard on semantic analysis in Libadalang, it is already possible to leverage its lexical and syntactic analyzers. A useful example for this is a syntax highlighter.

#Libadalang    #Ada   

by Pierre-Marie de Rodat

Pretty-Printing Ada Containers with GDB Scripts

When things don’t work as expected, developers usually do one of two things: either add debug prints to their programs, or run their programs under a debugger. Today we’ll focus on the latter activity.


by Yannick Moy

Applied Formal Logic: Searching in Strings

A friend pointed me to recent posts by Tommy M. McGuire, in which he describes how Frama-C can be used to functionally prove a brute force version of string search, and to find a previously unknown bug in a faster version of string search called quick search. Frama-C and SPARK share similar history, techniques and goals. So it was tempting to redo the same proofs on equivalent code in SPARK, and completing them with a functional proof of the fixed version of quick search. This is what I'll present in this post.

#Dev Projects    #Formal Verification    #SPARK   

by Rob Tice

The Adaroombot Project

The Adaroombot project consists of an iRobot CreateⓇ 2 and Ada running on a Raspberry Pi with a Linux OS. This is a great Intro-to-Ada project as it focuses on a control algorithm and a simple serial communications protocol. The iRobot CreateⓇ 2 platform was originally design for STEM education and has great documentation and support - making it very easy to create a control application using Ada. This blog looks at the creation of the project and some cool features of Ada that were learned along the way.

#Raspberry Pi    #ARM    #Linux    #Ada    #Roomba   

by Fabien Chouteau

Ada on the first RISC-V microcontroller

Updated July 2018

#Embedded Development    #Ada    #RISC-V   

by Yannick Moy

Research Corner - FLOSS Glider Software in SPARK

Two years ago, we redeveloped the code of a small quadcopter called Crazyflie in SPARK, as a proof-of-concept to show it was possible to prove absence of run-time errors (no buffer overflows, not division by zero, etc.) on such code. The researchers Martin Becker and Emanuel Regnath have raised the bar by developing the code for the autopilot of a small glider in SPARK in three months only. Their paper and slides are available, and they have released their code as FLOSS for others to use/modify/enhance!

#Formal Verification    #Dev Projects    #SPARK   

by Fabien Chouteau

DIY Coffee Alarm Clock

A few weeks ago one of my colleagues shared this kickstarter project : The Barisieur. It’s an alarm clock coffee maker, promising to wake you up with a freshly brewed cup of coffee every morning. I jokingly said “just give me an espresso machine and I can do the same”. Soon after, the coffee machine is in my office. Now it is time to deliver :)

#Embedded Development    #STM32    #Makers    #Ada    #ARM   

by Yannick Moy, Nicolas Roche

A Usable Copy-Paste Detector in A Few Lines of Python

After we created lightweight checkers based on the recent Libadalang technology developed at AdaCore, a colleague gave us the challenge of creating a copy-paste detector based on Libadalang. It turned out to be both easier than anticipated, and much more efficient and effective than we could have hoped for. In the end, we hope to use this new detector to refactor the codebase of some of our tools, and we expect to integrate it in our IDEs.

#Libadalang    #Static Analysis    #refactoring   

by Yannick Moy

VerifyThis Challenge in SPARK

This year again, the VerifyThis competition took place as part of ETAPS conferences. This is the occasion for builders and users of formal program verification platforms to use their favorite tools on common challenges. The first challenge this year was a good fit for SPARK, as it revolves around proving properties of an imperative sorting procedure. In this post, I am using this challenge to show how one can reach different levels of software assurance with SPARK.

#Formal Verification    #SPARK   

by Anthony Leonardo Gracio

GPS for bare-metal developers

In my previous blog article, I exposed some techniques that helped me rewrite the Crazyflie’s firmware from C into Ada and SPARK 2014, in order to improve its safety.

#GPS    #Embedded Development    #Makers   

by Yannick Moy

GNATprove Tips and Tricks: Proving the Ghost Common Divisor (GCD)

Euclid's algorithm for computing the greatest common divisor of two numbers is one of the first ones we learn in school, and also one of the first algorithms that humans devised. So it's quite appealing to try to prove it with an automatic proving toolset like SPARK. It turns out that proving it automatically is not so easy, just like understanding why it works is not so easy. In this post, I am using ghost code to prove correct implementations of the GCD, starting from a naive linear search algorithm and ending with Euclid's algorithm.

#Formal Verification    #SPARK   

by Pierre-Marie de Rodat

GNATcoverage moves to GitHub

Following the current trend, the GNATcoverage project moves to GitHub! Our new address is:

#GitHub    #GNATcoverage   

by Claire Dross

Research Corner - Auto-active Verification in SPARK

GNATprove performs auto-active verification, that is, verification is done automatically, but usually requires annotations by the user to succeed. In SPARK, annotations are most often given in the form of contracts (pre and postconditions). But some language features, in particular ghost code, allow proof guidance to be much more involved. In a paper we are presenting at NASA Formal Methods symposium 2017, we describe how an imperative red black tree implementation in SPARK was verified using intensive auto-active verification.

#Formal Verification    #SPARK   

by Pat Rogers

Getting started with the Ada Drivers Library device drivers

The Ada Drivers Library (ADL) is a collection of Ada device drivers and examples for ARM-based embedded targets. The library is maintained by AdaCore, with development originally (and predominantly) by AdaCore personnel but also by the Ada community at large.  It is available on GitHub and is licensed for both proprietary and non-proprietary use.

#Ada    #Devices    #drivers    #STM32    #embedded   

by Raphaël Amiard, Yannick Moy, Pierre-Marie de Rodat

Going After the Low Hanging Bug

At AdaCore, we have a strong expertise in deep static analysis tools (CodePeer and SPARK), and we have been relying on the compiler GNAT and our coding standard checker GNATcheck to deal with more syntactic or weakly-semantic checks. The recent Libadalang technology, developed at AdaCore, provided us with an ideal basis to develop specialized light-weight static analyzers. As an experiment, we implemented two simple checkers using the Python binding of Libadalang. The results on our own codebase were eye-opening: we found a dozen bugs in the codebases of the tools we develop at AdaCore (including the compiler and static analyzers).

#Static Analysis   

by Raphaël Amiard, Pierre-Marie de Rodat

Introducing Libadalang

AdaCore is working on a host of tools that works on Ada code. The compiler, GNAT, is the most famous and prominent one, but it is far from being the only one. At AdaCore, we already have several other tools to process Ada code: the ASIS library, GNAT2XML, the GPS IDE. A realization of the past years, however, has been that we were lacking a unified solution to process code that is potentially evolving, potentially incorrect Ada code. Hence Libadalang.

#Ada    #tooling   

by Fabien Chouteau

Make with Ada: DIY instant camera

There are moments in life where you find yourself with an AdaFruit thermal printer in one hand, and an OpenMV camera in the other.

#Makers    #Ada    #STM32    #ARM    #Embedded Development   

by AdaCore Admin

Make With Ada Winners Announced!

Judging for the first annual Make with Ada competition has come to an end and we can now reveal the results.

by Quentin Ochem

Unity & Ada

Using Ada technologies to develop video games doesn’t sound like an an obvious choice - although it seems like there could be an argument to be made. The reverse, however, opens some more straightforward perspectives.

#GitHub    #Ada    #GNAT    

by Emmanuel Briot

GNAT Programming Studio (GPS) on GitHub

The GPS source repository has been published on GitHub. This post briefly describes how you can access it, and hopefully contribute.

#GPS    #GitHub   

by AdaCore Admin

Introducing the Make With Ada competition!

If you’ve been looking for a way to start your next embedded project in Ada or SPARK. Then, look no further than the Make with Ada competition!

#MakewithAda    #embedded    #SPARK     #Ada   

by Fabien Chouteau

Make with Ada: ARM Cortex-M CNC controller

I started this project more than a year ago. It was supposed to be the first Make with Ada project but it became the most challenging from both, the hardware and software side.

#Makers    #Ada    #STM32    #ARM    #Embedded Development   

by Fabien Chouteau

Make with Ada: Candy dispenser, with a twist...

A few months ago, my colleague Rebecca installed a candy dispenser in our kitchen here at AdaCore. I don’t remember how exactly, but I was challenged to make it more… fun.

by Jérôme Lambourg

Porting the Ada Runtime to a new ARM board

A step by step tutorial to adapt the ARM runtime to new MCUs/boards.

#Bareboard    #ARM    #GNAT     #STM32    #Ravenscar   

by Fabien Chouteau

Make with Ada: Formal proof on my wrist

When the Pebble Time kickstarter went through the roof, I looked at the specification and noticed the watch was running on an STM32F4, an ARM cortex-M4 CPU which is supported by GNAT. So I backed the campaign, first to be part of the cool kids and also to try some Ada hacking on the device.

#SPARK2014     #Smartwatch    #Makers   

by Emma Adby

Modernizing Adacore's Open-Source Involvement

Through the adoption of GitHub we have taken our first step on the way to having a more collaborative and dynamic interaction with, both our users and open source technologies.

#GitHub    #OSS    #Ada   

by Yannick Moy

New Book About SPARK 2014

I am very pleased to announce that a book is now available for those who want to learn formal verification with SPARK 2014. This book was written by Prof. John McCormick from University of Northern Iowa and Prof. Peter Chapin from Vermont Technical College. We've been interacting a lot with them since they started in 2013, and the result of these interactions is quite satisfying!

#SPARK    #Formal Methods    #Teaching   

by Raphaël Amiard

Make with Ada : From bits to music

I started out as an electronic musician, so one of my original motivations when I learnt programming was so that I could eventually *program* the sounds I wanted rather than just use already existing software to do it.

#Makers    #Ada    #Embedded Development   

by Fabien Chouteau

Make with Ada: "The Eagle has landed"

July 20, 1969, 8:18 p.m. UTC, while a bunch of guys were about to turn blue on Earth, commander Neil A. Armstrong confirms the landing of his Lunar Module (LM), code name Eagle, on the moon. Will you be able to manually land Eagle on the Sea of Tranquillity?

#Makers    #NASA    #GtkAda    #Ada 2012   

by Fabien Chouteau

Make with Ada: All that is useless is essential

A few weeks ago I discovered the wonderful world of solenoid engines. The idea is simple: take a piston engine and replace explosion with electromagnetic field. In this article I will experiment a solenoid engine using a hacked hard drive and a software controller on a STM32F4 .

#Makers    #Ada    #Embedded Development    #Devices    #STM32   

by Anthony Leonardo Gracio

How to prevent drone crashes using SPARK

The Crazyflie is a very small quadcopter sold as an open source development platform: both electronic schematics and source code are directly available on their GitHub and its architecture is very flexible. Even if the Crazyflie flies out of the box, it has not been developed with safety in mind: in case of crash, its size, its weight and its plastic propellers won’t hurt anyone! But what if the propellers were made of carbon fiber, and shaped like razor blades to increase the drone’s performance? In theses circumstances, a bug in the flight control system could lead to dramatic events. In this post, I present the work I did to rewrite the stabilization system of the Crazyflie in SPARK 2014, and to prove that it is free of runtime errors. SPARK also helped me to discover little bugs in the original firmware, one of which directly related with overflows. Besides the Crazyflie, this work could be an inspiration for others to do the same work on larger and more safety-critical drones.

#UAVs    #crazyflie    #SPARK    #Drones   

by Yannick Moy

Using SPARK to Prove AoRTE in Robot Navigation Software

Correctness of robot software is a challenge. Just proving the absence of run-time errors (AoRTE) in robot software is a challenge big enough that even NASA has not solved it. Researchers have used SPARK to do precisely that for 3 well-known robot navigation algorithms. Their results will be presented at the major robotics conference IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2014) this coming September.

#Formal Verification    #SPARK    #Robotics