Re: GDB 15/16 crashing in add_thread_silent()

Simon Marchi via Gdb <[email protected]> Tue, 18 Nov 2025 15:24:50 -0500
Newsgroups gmane.comp.gdb.devel
Message-ID <[email protected]>
On 11/18/25 2:30 PM, Paul Smith via Gdb wrote:
> On Tue, 2025-11-18 at 11:33 -0700, Tom Tromey wrote:
>>>>>>> "Paul" == Paul Smith via Gdb <[email protected]> writes:
>>
>> [...]
>> Paul> So, there appears to be some difference in binutils where it can't
>> Paul> parse this core file properly...?
>>
>> Yes, interesting find.
>> Unfortunately the next step is probably to bisect binutils to find
>> the offending patch.  Or I guess debug and try to find what's going
>> wrong.
> 
> Yeah.  Unfortunately I will need to gird myself for that and I have a
> lot of other things happening.  Bisecting will be a big job since we're
> jumping from binutils 2.30 (known to work) to binutils 2.43 (known to
> not work).
> 
> It's probably worthwhile making some effort at debugging, to try to
> narrow down the locations in the code to consider during bisecting.  It
> looks like somehow we cannot determine the PID / TID properly in this
> core file in newer binutils, while the older binutils can still dig it
> out.  Unfortunately I've never looked at any of this code before but
> hopefully it will be tractable.
> 
> Maybe this weekend I can spend a bit of time on this.

The beauty of bisecting is that the number of steps grows logarthmically
with the number of commits, so it's not that long :).  If you are
allowed to share the core file, I wouldn't mind giving it a try.
Bisecting stuff is one of my favorite pastimes.

Simo