Pending breakpoints

Pending breakpoints

[Russell Shaw]

Hi,
I'm debugging a project with dlopen-ed modules.

In gdb, setting a breakpoint for an as-yet unloaded symbol
makes gdb say:

   (gdb) b func_realize
   Function "func_realize" not defined.
   Make breakpoint pending on future shared library load? (y or [n]) y
   Breakpoint 1 (func_realize) pending.


However, the dialog doesn't happen in DDD, making it useless.

I'm using it on debian:

   GNU DDD 3.3.11 (i486-pc-linux-gnu)
   GNU gdb 6.4.90-debian

Re: Pending breakpoints

[Daniel Jacobowitz]

On Sat, Oct 21, 2006 at 01:28:23PM +1000, Russell Shaw wrote:
> Hi,
> I'm debugging a project with dlopen-ed modules.
> 
> In gdb, setting a breakpoint for an as-yet unloaded symbol
> makes gdb say:
> 
>   (gdb) b func_realize
>   Function "func_realize" not defined.
>   Make breakpoint pending on future shared library load? (y or [n]) y
>   Breakpoint 1 (func_realize) pending.
> 
> 
> However, the dialog doesn't happen in DDD, making it useless.

That's a problem with ddd, then; ask them.  Meanwhile, set break
pending on may help, but who knows how badly that will confuse ddd.

-- 
Daniel Jacobowitz
CodeSourcery

Re: Pending breakpoints

[Russell Shaw]

Daniel Jacobowitz wrote:
> On Sat, Oct 21, 2006 at 01:28:23PM +1000, Russell Shaw wrote:
> 
>>Hi,
>>I'm debugging a project with dlopen-ed modules.
>>
>>In gdb, setting a breakpoint for an as-yet unloaded symbol
>>makes gdb say:
>>
>>  (gdb) b func_realize
>>  Function "func_realize" not defined.
>>  Make breakpoint pending on future shared library load? (y or [n]) y
>>  Breakpoint 1 (func_realize) pending.
>>
>>However, the dialog doesn't happen in DDD, making it useless.
> 
> That's a problem with ddd, then; ask them.  Meanwhile, set break
> pending on may help, but who knows how badly that will confuse ddd.

Hi,
That worked ok. Now there's a bug in gdb (when run stand-alone).

The dlopened module is loaded, the breakpoint symbol is resolved,
but the program continues running instead of stopping at the
breakpoint. I'll look into gdb source myself.

Pending breakpoints

[Russell Shaw]

Hi,
In breakpoint.c:break_command_1():line-5214, "pending = 1" is set
when do_captured_parse_breakpoint() does not find a breakpoint.

Does this only ever happen with unloaded shared libraries, or can
other things like overlays cause it too?

Re: Pending breakpoints

[Jim Blandy]

Russell Shaw <rjshaw@netspace.net.au> writes:
> In breakpoint.c:break_command_1():line-5214, "pending = 1" is set
> when do_captured_parse_breakpoint() does not find a breakpoint.
>
> Does this only ever happen with unloaded shared libraries, or can
> other things like overlays cause it too?

Breakpoints in overlays are never made pending.  So I think that's
just for shared libraries.