Re: Breakpoint commands in MI mode and "backtrace"

Eli Zaretskii
2017-10-09T07:52:54Z

> Date: Mon, 09 Oct 2017 10:27:15 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> CC: gdb@sourceware.org
>
> > Cc: gdb@sourceware.org
> > From: Simon Marchi <simark@simark.ca>
> > Date: Mon, 9 Oct 2017 00:16:28 -0400
> >
> > Hmm, strange. It is a quite complex function being executed in the hookpost-backtrace.
> > Do you have any idea what line generates the error? It would be nice to have a
> > reproducer without having to build emacs...
>
> It's this line in xgetsysm:
>
> set $ptr = ((struct Lisp_Symbol *) ((char *)lispsym + $ptr))
>
> where $ptr is a pointer to a Lisp_Symbol object:
>
> (gdb) p $ptr
> $2 = (struct Lisp_Symbol *) 0x17c9e38 <dumped_data+267384>
>
> and lispsym is an array:
>
> (gdb) ptype lispsym
> type = struct {
> struct Lisp_Symbol s;
> } [1298]
>
> Let me know if I can provide more information about this.

Btw, with the patch, I get the same error if I invoke GDB in CLI mode.

Thanks.