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Re: Cannot insert breakpoint -1.


Anmol P. Paralkar wrote:
On Fri, 24 Jul 2009, Daniel Jacobowitz wrote:

On Fri, Jul 24, 2009 at 05:00:45PM -0500, Anmol P. Paralkar wrote:
Yes, I see:

(gdb) maintenance info breakpoints Num     Type           Disp Enb
Address    What
-1      shlib events   keep y   0x00110000 <_start>

How do I delete it/prevent it from being set? Is this a configure
time setting?

It may help to use a powerpc-elf debugger instead.

I tried powerpc-elf GDB, and it'll work (I see that I cannot set a breakpoint in the application - but that seems to be a problem with the application itself).

--

  I do have one question about powerpc-linux-gnu GDB; I see that the breakpoint
  is inserted inspite of:

(gdb) show stop-on-solib-events
Stopping for shared library events is 0.

--

From breakpoint.h:

     /* Some dynamic linkers (HP, maybe Solaris) can arrange for special
        code in the inferior to run when significant events occur in the
        dynamic linker (for example a library is loaded or unloaded).

        By placing a breakpoint in this magic code GDB will get control
        when these significant events occur.  GDB can then re-examine
        the dynamic linker's data structures to discover any newly loaded
        dynamic libraries.  */
     bp_shlib_event,

--

  I would assume that if stop-on-solib-events is 0, then it ought not to set
  the -1 breakpoint. Please could you help understanding this part.

Anmol,


"stop-on-solib-events" means 'stop' as in "show the user a gdb prompt".

If it's unset, we still insert the breakpoints so that we can
handle the shared library events (read symbol files), we just
don't go to the interactive prompt.

I think it's really unusual for someone to want to actually
go to the prompt when a shared lib event occurs, but normally
we want symbols to be loaded.  Don't know if there's any way
to actually disable that...

Michael


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