getting source line numbers from printed exit backtrace

getting source line numbers from printed exit backtrace

[Madhu]

When emacs (compiled with -g3 -O2) crashes, it prints out stuff
```
Backtrace:
/14/build/emacs/build-gtk/src/emacs[0x574a3b]
/14/build/emacs/build-gtk/src/emacs[0x426475]
/14/build/emacs/build-gtk/src/emacs[0x426967]
/14/build/emacs/build-gtk/src/emacs[0x572fa8]
/14/build/emacs/build-gtk/src/emacs[0x573019]
/lib64/libc.so.6(+0x3d240)[0x7f78855c2240]
/usr/lib64/libgtk-3.so.0(gtk_widget_get_window+0x19)[0x7f7887b125b9]
```

Can I get the source information corresponding to these printed
frames?

I've seen messages on the mailing list where people were asked to post
this sort of crash information on released microsoft windows builds
(without debug info), and an emacs dev could figure out the
information with access to the full debug libraries, but I've
forgotten how it is done.

--- Madhu

Re: getting source line numbers from printed exit backtrace

[Eli Zaretskii]

> Date: Fri, 26 May 2023 14:23:40 +0530 (IST)
> From: Madhu <enometh@meer.net>
> 
> When emacs (compiled with -g3 -O2) crashes, it prints out stuff
> ```
> Backtrace:
> /14/build/emacs/build-gtk/src/emacs[0x574a3b]
> /14/build/emacs/build-gtk/src/emacs[0x426475]
> /14/build/emacs/build-gtk/src/emacs[0x426967]
> /14/build/emacs/build-gtk/src/emacs[0x572fa8]
> /14/build/emacs/build-gtk/src/emacs[0x573019]
> /lib64/libc.so.6(+0x3d240)[0x7f78855c2240]
> /usr/lib64/libgtk-3.so.0(gtk_widget_get_window+0x19)[0x7f7887b125b9]
> ```
> 
> Can I get the source information corresponding to these printed
> frames?

Yes, see the node "Crashing" in the Emacs manual.

Re: getting source line numbers from printed exit backtrace

[Basile Starynkevitch]

On 5/26/23 11:11, Eli Zaretskii wrote:
>> Date: Fri, 26 May 2023 14:23:40 +0530 (IST)
>> From: Madhu <enometh@meer.net>
>>
>> When emacs (compiled with -g3 -O2) crashes, it prints out stuff
>> ```
>> Backtrace:
>> /14/build/emacs/build-gtk/src/emacs[0x574a3b]
>> /14/build/emacs/build-gtk/src/emacs[0x426475]
>> /14/build/emacs/build-gtk/src/emacs[0x426967]
>> /14/build/emacs/build-gtk/src/emacs[0x572fa8]
>> /14/build/emacs/build-gtk/src/emacs[0x573019]
>> /lib64/libc.so.6(+0x3d240)[0x7f78855c2240]
>> /usr/lib64/libgtk-3.so.0(gtk_widget_get_window+0x19)[0x7f7887b125b9]
>> ```
>>
>> Can I get the source information corresponding to these printed
>> frames?
> Yes, see the node "Crashing" in the Emacs manual.



BTW, on Linux systems, GNU emacs could use Ian Lance Taylor's 
libbacktrace library for that purpose. (readability of backtrace)

That library is included in recent GNU GCC compiler, and is downloadable 
from https://github.com/ianlancetaylor/libbacktrace

(and that library is also used in the RefPerSys open source inference 
engine on https://github.com/RefPerSys/RefPerSys described on 
http://refpersys.org/ for which contributors are welcome).


Regards.


-- 
Basile Starynkevitch                  <basile@starynkevitch.net>
(only mine opinions / les opinions sont miennes uniquement)
92340 Bourg-la-Reine, France
web page: starynkevitch.net/Basile/