How to debug linux crashes
 

I've compiled the linux *so file of podbot_mm, gave it to KaszpiR and he says - "yes - this version crashes not so often (it's more stable) like the version in package R2B46d, but still it crashes. He gave me the info from logs of his server. How to find the problem if linux HLDS reports such below crashes?
The filse has been created as it was described in this topic.
CRASH: Wed Jan 4 01:08:02 CET 2006
Start Line: ./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +maxplayers 20 +exec server.cfg +map de_dust -pidfile hlds.15735.pid
Using host libthread_db library "/lib/tls/libthread_db.so.1".
Core was generated by `./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +'.
Program terminated with signal 11, Segmentation fault.
#0 0x00289dd9 in ?? ()
#0 0x00289dd9 in ?? ()
End of crash report
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CRASH: Wed Jan 4 07:56:39 CET 2006
Start Line: ./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +maxplayers 20 +exec server.cfg +map de_dust -pidfile hlds.15735.pid
Using host libthread_db library "/lib/tls/libthread_db.so.1".
Core was generated by `./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +'.
Program terminated with signal 11, Segmentation fault.
#0 0x02812dd9 in ?? ()
#0 0x02812dd9 in ?? ()
End of crash report

Re: How to debug linux crashes
 

aditionally crashers were reported on cs_backalley (twice so far) and cs_havana

in previous versions i rember the most crahshable map was de_chateau

tests on

Distro Name Fedora Core release 3 (Heidelberg)
Kernel Version 2.6.9-1.667

Ram: 256Mb

Processors 1 Model Intel(R) Pentium(R) 4 CPU 1.80GHz
CPU Speed 1.79 GHz
Cache Size 256 KB
System Bogomips 3538.94
IDE interface: Intel Corp. 82801BA IDE U100
00:1f.3 SMBus: Intel Corp. 82801BA/BAM SMBus
00:1f.5 Multimedia audio controller: Intel Corp. 82801BA/BAM AC'97 Audio
01:00.0 VGA compatible controller: nVidia Corporation NV5 [RIVA TNT2/TNT2 Pro]
02:08.0 Ethernet controller: Intel Corp. 82801BA/BAM/CA/CAM Ethernet Controller

IDE Devices hda: ST340016A (Capacity: 37.29 GB)
hdb: IBM-DTLA-305020 (Capacity: 19.00 GB)
hdc: LTN486S

Re: How to debug linux crashes
 

compile with the paramater -g3 and use gdb to debug it.
it will tell you the exact place of the crash.

Re: How to debug linux crashes
 

n00b's question - I don't know what is "gdb" - is this some tool for debugging? Is there a topic how to use it (or some manual for n00bs)? Does it mean that gdb (if it's a tool) needs to be fired-up on that server to show the crash place?

Re: How to debug linux crashes
 

gdb = GNU Debugger

I don't have a step by step tutorial but here is its current official web site:
http://www.gnu.org/software/gdb/
Hope you can find some useful information there.
Or try the help file of gdb:
$ info gdb

There are also some GUI-based debuggers such as RedHat Insight or KDbg (portion of KDE) which may be easier.

Re: How to debug linux crashes
 

i got a gdb as default debugger on hlds (and it is a default debugger if running hlds with -debug parameter)

Re: How to debug linux crashes
 

After the game crashed (in gdb) just type 'backtrace' to see what the latest called functions where. Also if the game didn't ran in gdb but produced a .core file, you can open it with gdb using the -c parameter, then also just type backtrace.

Re: How to debug linux crashes
 

hmm maybe i should modify hlds_runa nd add there the backtrace commadn, so it would export it to file?

just got the crash on modded .so form KWo (compiled with -g3) on cs_havana, 16bots
did as you said

(well the same gives gdb run, no wonder ;P)



and as you may expect in .log file

Re: How to debug linux crashes
 

OK - that -g3 flag I've put in wrong place abnd it ddn't affect at all the compilation. Now KaszpiR has the correct so (correctly compiled with -g3) and we will wait for the next crash report. I hope it will be now more helpful :)

Re: How to debug linux crashes
 

debug.log on KaszpiR's PC still says nothing...
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CRASH: Thu Jan 5 23:11:16 CET 2006
Start Line: ./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +maxplayers 20 +exec server.cfg +map de_chateau -pidfile hlds.7326.pid
Using host libthread_db library "/lib/tls/libthread_db.so.1".
Core was generated by `./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +'.
Program terminated with signal 11, Segmentation fault.
#0 0x00dc6689 in ?? ()
#0 0x00dc6689 in ?? ()
End of crash report
----------------------------------------------
----------------------------------------------
CRASH: Fri Jan 6 00:09:22 CET 2006
Start Line: ./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +maxplayers 20 +exec server.cfg +map de_chateau -pidfile hlds.7326.pid
Using host libthread_db library "/lib/tls/libthread_db.so.1".
Core was generated by `./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +'.
Program terminated with signal 11, Segmentation fault.
#0 0x05072689 in ?? ()
#0 0x05072689 in ?? ()
End of crash report
----------------------------------------------
----------------------------------------------
CRASH: Fri Jan 6 07:12:38 CET 2006
Start Line: ./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +maxplayers 20 +exec server.cfg +map de_chateau -pidfile hlds.7326.pid
Using host libthread_db library "/lib/tls/libthread_db.so.1".
Core was generated by `./hlds_i686 -game cstrike -debug +sv_lan 1 +log on -insecure -nomaster -nodns +'.
Program terminated with signal 11, Segmentation fault.
#0 0x0431f689 in ?? ()
#0 0x0431f689 in ?? ()
End of crash report
----------------------------------------------

I'm sure it was compiled with -g3 flag (used as one of CFLAGS).
Maybe I should use -ggdb3 instead -g3? Do these flags whole works correctly for cygwin? Maybe they arefor mingw only and cygwin needs another one to give me more helpful info?