Tutorial: Catching Rogue Memory Accesses with Eclipse and GDB Watchpoints

Eclipse is great: it gives me the tools and capabilities to solve the really hard bugs to find. An example of that ‘hard’ category are ‘rogue’ memory accesses: something in the application is accessing an unwanted memory location and corrupts the data. This might be very sporadic, or takes a long while until it happens. With normal ‘stop-mode’ debugging (setting a normal breakpoint) and stepping usually won’t let me find that bug, as it might be coming from a pointer somewhere. Maybe from an interrupt routine. Or maybe an unitialized or corrupted pointer corrupts to my memory. Usually all what I know is the memory adddress of the data, maybe what is written, but not what or who is writing to that location.

In this article I’m using one of the ‘less-known’ debugging techniques available in Eclipse and CDT and how it works: watchpoints!

Watchpoint with Condition

Watchpoint with Condition

In this article I’m using one of the ‘less-known’ debugging techniques available in Eclipse and CDT and how it works: watchpoints!

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Debug the Last Launched Application with Eclipse and other Debug Tricks

My usual workflow is: edit – build – debug and repeat. And this for the same project again and again. So here are a few tips how to make these iterations faster with Eclipse. One thing is to use the F11 shortcut to debug the last launched/debugged application:

Debug Last Launched

Debug Last Launched

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Managing Project and Library Dependencies with Eclipse CDT

For several projects I’m using library projects: I build a library and then use that library in the other project. If I change something in a library, I want to run make both on the referenced libraries and rebuild my application if needed. If you don’t know how to do this, then read on… 🙂

Shared Library Projects

Shared Library Projects

(… actually it means workign around  known Eclipse CDT bug too….)

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Transforming Eclipse Linked Projects into Standalone Projects

Some silicon vendors provide their Eclipse example and SDK projects using linked files and folders. For example a bootloader demo application is provided in the context of an SDK or library. That’s fine until the time I want to transform such an example into a real project or if I want to have it without the hundreds of files for all the other devices I don’t need or use. I cannot take the project and put it into a version control system as the linked files won’t be in my VCS. I cannot move the project to another place as the links are pointing to many places. What I need is a ‘standalone’ project: a project which has all the needed files in it and is self-containing.

Eclipse Project with Linked Files

Eclipse Project with Linked Files and virtual groups

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Automatically Refresh Eclipse Projects before Build

The Eclipse CDT build system automatically scans the files in my project folders and adds them to the list of files to be built. That works great if files are added through Eclipse and its plugins: That way Eclipse is notified and aware, and has the files added. But what if I have added files externally (outside of Eclipse)? how can I make Eclipse aware of it?

File added but not shown

File added but not shown in Eclipse Project View

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Assembly Files in Eclipse CDT Projects

My embedded applications are implemented mostly in C, a few in C/C++. But all of them have one or few assembly files included too: Assembly programming is the needed to do low-level things so it is a natural part of a true embedded application. For example I use often an assembly file for the application startup code.

I have run into a nasty Eclipse CDT issue which deals with assembly files projects. Here is a quizz for you: can you spot the problem in my project below?

Startup Assembly Code

Startup Assembly Code

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