Crash of GDB with gdbserver btrace enabled [Re: [patch v9 00/23] branch tracing support for Atom]

[Metzger, Markus T]

> -----Original Message-----
> From: Metzger, Markus T
> Sent: Thursday, March 07, 2013 10:41 AM


> Another approach would be to change pop_target to unpush the top target
> instead of just closing it.  This would prevent btrace from finding a target to
> disable tracing and all I would need to do is remove the tcomplain call in
> target_disable_btrace.
> 
> This would be quite elegant but I have no clue about the side effects this
> might have.

void
pop_target (void)
{
  target_close (target_stack, 0);	/* Let it clean up.  */
  if (unpush_target (target_stack) == 1)
    return;

  fprintf_unfiltered (gdb_stderr,
		      "pop_target couldn't find target %s\n",
		      current_target.to_shortname);
  internal_error (__FILE__, __LINE__,
		  _("failed internal consistency check"));
}

Isn't pop_target closing the topmost target twice?

When I remove the first call to target_close and do not turn errors into
warnings in record_btrace_close, the crash is gone.  I have no clue about
the side effects of this, though.


Regards,
Markus.
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