Re: Development environment (BIS)

[Jason Alexander]

On 8 Jan 2000, Marcus G. Daniels wrote:

> 7) My impression is that there are a quite a few people that use
>    Objective C Swarm but don't really know how to use gdb.  I suppose
>    for these people debugging is done by tomography and by scrutinizing
>    model code.  These folks might as well use Java.

Is there a version of gdb which fully supports Objective C?  I believe
versions 4.17 and 4.18 are broken with respect to ObjC.  Version 4.16, the
which I'm using (a hacked-up one downloaded from SFI), doesn't seem to
support various things that I might want to do, like printing ivars
belonging to various objects and calling functions:


Breakpoint 2, -[ModelSwarm buildObjects] (self=0x80a5c60, _cmd=0x805c750)
    at ModelSwarm.m:84
84        game = [Game create: self];
(gdb) n         
85        worldXSize = [parameterManager getWorldXSize];
(gdb) print game
evaluation of this expression requires the program to have a function
"objc_lookup_class".
(gdb) call getWorldXSize
evaluation of this expression requires the program to have a function
"objc_lookup_class".
(gdb) call [parameterManager getWorldXSize]
evaluation of this expression requires the program to have a function
"objc_lookup_class".


If these problems derive from ignorance in using gdb, my apologies.  But I
do seem to remember hearing that even the hacked-up version of gdb from
SFI doesn't provide the full range of gdb commands available for debugging
other languages (like C) for ObjC.

My theory is that (1) gdb's support for ObjC is somewhat iffy, and (2)
were gdb's support for ObjC better, more people would use it (this might
be too optimistic, though). 

If I'm wrong about (1), please let me know.

Thanks,

Jason


                  ==================================
   Swarm-Support is for discussion of the technical details of the day
   to day usage of Swarm.  For list administration needs (esp.
   [un]subscribing), please send a message to <address@hidden>
   with "help" in the body of the message.