Re: Can't debug x86_64 C++ programs.

[Keith Seitz <keiths at redhat dot com>]

John Fine wrote:

> So I wasted lots of time trying to use
> fprintf_unfiltered (gdb_stdlog,
>
> Then I realized most of those were just trying to pop up in a window 
> when Insight crashed, so I would never get to see them.

Yeah, the *_unfilitered and *_filtered all head through uiout, which are 
redirected to insight and tcl/tk. As you discovered, you need to use 
"normal" printfs.

> I think architecture_changed_event OUGHT to call 
> setup_architecture_data, but I can't tell from the source code what it 
> actually does or who calls setup_architecture_data.

Here's what going on. When you load your x86_64 executable, gdb notices 
that this is different from the current i386 architecture, so it changes 
the current architecture to i386:x86_64. When this is changed, an 
observer notification is fired off from 
deprecated_current_gdbarch_select_hack (deprecated? I guess gdb doesn't 
want anyone to know that the architecture has changed??).

Insight registers gdbtk_architecture_changed as the observer callback. 
This then calls the Tcl procedure gdbtk_tcl_architecture_changed, which 
dispatches this event to the windows. The register window is currently 
the only window that does anything with this event.

It calls the proc gdb_reg_arch_changed, which is aliased to the C 
function setup_architecture_data. [Phew!] So, alas, 
setup_architecture_data *is* being called.

This will require further investigation.

Keith