Re: extending Gdb to display app specific data

[Michael Meissner <meissner at cygnus dot com>]

On Fri, Nov 10, 2000 at 04:08:57PM -0800, Brian Stell wrote:
> We all agree that gdb by itself cannot display every data
> type that will come along.
> 
> What I'm looking for is a way for an expert user to tell
> gdb how to display a given type. This way within a
> community of developers the expert users can setup
> display routines for the complex data types in that
> environment and everyone else can view the data
> in gdb.
> 
> For example, in the Mozilla development world there are a
> large number of developers and a variety of string formats
> (PRUnichar=UTF16, nsString=C++ object, etc.) and more
> are expected in the future (e.g.: a compressed format).
> 
> It is easy to say RTFM but it would be more effective
> to say "copy this file to your home dir".

Do like GCC does and include functions in your code that take your type as an
argument, and print the type in question to stdout (or stderr).  For example
within gcc, there is debug_rtx, which takes a rtx pointer, and prints out the
value in tree format, and similarly debug_tree which does it for tree nodes.
To further enhance the debugging experience, the .gdbinit command includes
several shortcuts (like pr/pt) that pass the last value to the above
functions.

-- 
Michael Meissner, Red Hat, Inc.
PMB 198, 174 Littleton Road #3, Westford, Massachusetts 01886, USA
Work:	  meissner@redhat.com		phone: +1 978-486-9304
Non-work: meissner@spectacle-pond.org	fax:   +1 978-692-4482