So I fire up my c++ application in GDB, and when it quits, I basically get:
[Thread 0x7fff76e07700 (LWP 6170) exited]
[Thread 0x7fff76f08700 (LWP 6169) exited]
[Thread 0x7fff77009700 (LWP 6168) exited]
Program terminated with signal SIGKILL, Killed. The program no longer exists.
I literally have no idea why this is occuring, why can’t I do a backtrace to see how it exited? Anyone have any ideas? It should never end 🙁
I literally have no idea why this is occuring,
This usually means that either
- some other process executed a
kill -9 <your-pid>, or
- the kernel OOM killer decided that your process consumed too many resources, and terminated it (effectively the kernel executed
kill -9 for it). You should look in
/var/log/syslog on Ubuntu variants) for traces of that — the kernel usually logs a message when it OOMs some process.
why can’t I do a backtrace to see how it exited?
Because in order to see a backtrace, the process must exist. If it doesn’t exist, it doesn’t have stack, and so can’t have backtrace.
If you are using Unix/Linux you should also be able to type
dmesg on your terminal and see the cause of the process terminating. In my case it was indeed OOM. here is a screenshot of my kernel log shortly after the termination
It is possible that the process ran into the cpu time ulimit. Check with ulimit -a from the environment where the process is actually started if “cpu time” is set to anything other than “unlimited”
In my case was a crash (AV). Even with GDB attached I couldn’t catch this violation.
Hope it helps