Linux Debug and Globals

Hi... well, after my testing, I've discovered that the Nios II IDE will *not* display global variables due to how debugging Nios II Linux applications work. I'll post some background at the end of this message.

If you need to debug global variables within your application code, I would recommend using nios2-elf-insight. PM me your e-mail address, and I'll send you a document outlining how to debug Nios II Linux applications through insight.

background

When starting a Nios II Linux application debug session, the debugger basically treats the kernel and application as one large Nios II standalone application.

In order to map the symbols within the application to the memory that's occupied by the application, the Nios II IDE performs an "add-symbol-file" command.

Unfortunately, the Nios II IDE/Eclipse doesn't recognize global variables from a symbol table that's pulled in using the "add-symbol-file" command. This explains why you can debug a standalone application and get access to the globals and why you can't in a Nios II Linux application debug session.

This doesn't mean that the global variables aren't available, it just can't be accessed through Nios II IDE at this point in time. To work around this, I would use either the nios2-elf-gdb program directly or I would use nios2-elf-insight which provides a Tcl/Tk graphical front end.

Please PM me for more info.