Kamal Prasad <kamalpr@yahoo.com> writes:

> I am using ddb in macppc-netbsd to look at
> panics,deadlocks etc.. I cannot/may not be able to
> -access this via gdb.
> assuming I have a stack from trace /t ... in ddb:-

> 1. How do I evaluate parameters to a function call
> inside a stack frame?

This is hard. Like most other RISC architectures, powerpc uses
registers to pass the first several (six for ppc) arguments. For
functions other than the most recent, the register values may be
stored on the stack, but only if their values were live at the moment
of the function call. You need something that can parse the full
debugging information built into a -g kernel to figure this out, and
even then you are likely to not have all the values saved any more.

> 2. the local variables inside a stack frame

Also requires parsing debug information beyond the basic symbol
table. I usually find it easist to have another computer with a
debugger or objdump, disassemble the functions in question, and
interpolate the storage locations of variables from the action of the
machine code.

        - Nathan