Re: GNAT exception traceback

[dewar@merv.cs.nyu.edu (Robert Dewar)]

Wes says

<<Definitely.  I can accept the notion that the overhead might be too
high, but I have trouble with the notion (as an outsider)
that it is a tremendous amount of development due to implementation-
dependence.  If gdb can do it on all its supported platforms, could
not some subset of gdb code be jammed into the RTS somewhere?>>

Feel free to jam away :-)

Seriously, this is a very big project, for all sorts of reasons. Wes, if
you do dig into it, you will quickly discover why. Basically the devil is
in the details as usual, but in this case, the details are very considerable.

Here is a little one: you need to have access to the debugging information
from within the program if you use this approach, and indeed you will need
large amounts of space to read in this debugging information (we hope that
the traceback you are trying give is not for Storage_Error). But getting
your hands on this information is not easy. But that's just for starters.


Whenever you have trouble with someone saying that X is a lot of work, and
you know nothing much about X, then probably the first step in verifying
the reasonableness of your trouble is to learn about X. So my invitation 
is as follows: dig away in the GDB code, and if you see a way of doing
this as simply as you feel should be possible, by all means suggest it!

Robert