Subject: Re: bug#76559: 31.0.50; [-O3 + PGTK] Crash when 'copying as kill'/'killing word'

From: Iurie Marian <[email-masked]>
Date: Wed, 26 Feb 2025 14:43:20 +0100

> What does this produce:
>  (gdb) p *event

(gdb) p *event
$1 = {kind = SELECTION_REQUEST_EVENT, ie = {kind =
SELECTION_REQUEST_EVENT, part = scroll_bar_nowhere, code = 0,
modifiers = 1439199584, x = 0x555555f95a80, y = 0x45, timestamp = 77,
frame_or_window = 0x5e, arg = 0x0, device = 0x30}, sie = {kind =
SELECTION_REQUEST_EVENT, dpyinfo = 0x55c87160, requestor =
0x555555f95a80, selection = 0x45, target = 0x4d, property = 0x5e, time
= 0}}

On Wed, 26 Feb 2025 at 14:10, Eli Zaretskii <[email-masked]> wrote:
>
> > Cc: Michael Albinus <[email-masked]>
> > From: Iurie Marian <[email-masked]>
> > Date: Tue, 25 Feb 2025 18:32:39 +0100
> >
> > Dear Maintainers,
> >
> > Emacs is crashing while copying-as-kill/killing-word, only when compiled
> > with -O3 optimizations. I am using PGTK (see the configure command
> > below). I did a git bisect, and it seems that the commit below is
> > triggering the bug. To reproduce it just compile with -O3 and PGTK, then
> > simply hit M-<backspace>.
> >
> > At the bottom you will also see the the stack trace, maybe it's useful.
>
> Is this still in GDB, and you can answer some questions about it?  Or,
> if not, then reproduce the crash and answer the questions then?
>
> > (gdb) info locals
> > event = 0x555555957a40 <kbd_buffer+384>
> > copy = {kind = SELECTION_REQUEST_EVENT, dpyinfo = 0x55cf0b00,
> > requestor = 0x555555f97a80, selection = 0x45, target = 0x4d, property
> > = 0x5e, time = 0}
> > moved_events = <optimized out>
> >
> > (gdb) x/s 0x55cf0b00
> > 0x55cf0b00:     <error: Cannot access memory at address 0x55cf0b00>
>
> What does this produce:
>
>  (gdb) p *event
>